--- type: "firecrawl-provider" description: "STRING (string-db.org, version 12.5; SIB, Novo Nordisk Foundation CPR and EMBL), the database of known and predicted protein-protein associations, through its public REST API (CC BY 4.0). Gives one protein's interaction partners or the network among a gene list in any of about 12,500 species, with STRING's combined confidence score and its seven evidence channels (neighborhood, gene fusion, co-occurrence, co-expression, experiments, curated databases, text mining), physical-only or functional associations, and the network's PPI enrichment p-value against chance. Runs functional enrichment of a gene list (Gene Ontology, Reactome, WikiPathways, UniProt keywords, Hallmark, COMPARTMENTS, TISSUES, DISEASES, InterPro, Pfam, PubMed, mammalian phenotypes) with FDR and the matched genes, limited to categories whose source licence permits commercial redistribution: KEGG, SMART and HPO terms are left out and counted. Names are mapped first (gene symbol, UniProt accession, Ensembl protein ID, STRING ID) and every answer names the STRING version, its licence and attribution." use_when: "STRING (string-db.org, version 12.5; SIB, Novo Nordisk Foundation CPR and EMBL), the database of known and predicted protein-protein associations, through its public REST API (CC BY 4.0). Gives one protein's interaction partners or the network among a gene list in any of about 12,500 species, with STRING's combined confidence score and its seven evidence channels (neighborhood, gene fusion, co-occurrence, co-expression, experiments, curated databases, text mining), physical-only or functional associations, and the network's PPI enrichment p-value against chance. Runs functional enrichment of a gene list (Gene Ontology, Reactome, WikiPathways, UniProt keywords, Hallmark, COMPARTMENTS, TISSUES, DISEASES, InterPro, Pfam, PubMed, mammalian phenotypes) with FDR and the matched genes, limited to categories whose source licence permits commercial redistribution: KEGG, SMART and HPO terms are left out and counted. Names are mapped first (gene symbol, UniProt accession, Ensembl protein ID, STRING ID) and every answer names the STRING version, its licence and attribution.\n\nSTRING (string-db.org, version 12.5; SIB, Novo Nordisk Foundation CPR and EMBL), the database of known and predicted protein-protein associations, through its public REST API (CC BY 4.0). Gives one protein's interaction partners or the network among a gene list in any of about 12,500 species, with STRING's combined confidence score and its seven evidence channels (neighborhood, gene fusion, co-occurrence, co-expression, experiments, curated databases, text mining), physical-only or functional associations, and the network's PPI enrichment p-value against chance. Runs functional enrichment of a gene list (Gene Ontology, Reactome, WikiPathways, UniProt keywords, Hallmark, COMPARTMENTS, TISSUES, DISEASES, InterPro, Pfam, PubMed, mammalian phenotypes) with FDR and the matched genes, limited to categories whose source licence permits commercial redistribution: KEGG, SMART and HPO terms are left out and counted. Names are mapped first (gene symbol, UniProt accession, Ensembl protein ID, STRING ID) and every answer names the STRING version, its licence and attribution." categories: "Life sciences" capabilities: 3 credits_per_call: 5 --- # STRING: protein interactions and functional enrichment on Firecrawl Alexandria STRING (string-db.org, version 12.5; SIB, Novo Nordisk Foundation CPR and EMBL), the database of known and predicted protein-protein associations, through its public REST API (CC BY 4.0). Gives one protein's interaction partners or the network among a gene list in any of about 12,500 species, with STRING's combined confidence score and its seven evidence channels (neighborhood, gene fusion, co-occurrence, co-expression, experiments, curated databases, text mining), physical-only or functional associations, and the network's PPI enrichment p-value against chance. Runs functional enrichment of a gene list (Gene Ontology, Reactome, WikiPathways, UniProt keywords, Hallmark, COMPARTMENTS, TISSUES, DISEASES, InterPro, Pfam, PubMed, mammalian phenotypes) with FDR and the matched genes, limited to categories whose source licence permits commercial redistribution: KEGG, SMART and HPO terms are left out and counted. Names are mapped first (gene symbol, UniProt accession, Ensembl protein ID, STRING ID) and every answer names the STRING version, its licence and attribution. - Categories: Life sciences - Category index: [Life sciences category](https://firecrawl.dev/alexandria/agents/categories/life-sciences) - Provider key: `string-db-org` - Access: Firecrawl credits - Cost: 5 credits per call ## More - [Human guide](https://firecrawl.dev/app/alexandria/string-db-org) - [OpenAPI spec](https://firecrawl.dev/alexandria/agents/providers/string-db-org/openapi.json) ## Capabilities - [Network](https://firecrawl.dev/alexandria/agents/providers/string-db-org/interactions/network): The interaction network among a list of 2 to 100 proteins in one species: every pair STRING scores at or above min_score, with the combined confidence score and the seven evidence channel scores, plus STRING's network statistics (nodes, edges against the number expected for random proteins, average node degree, clustering coefficient and the PPI enrichment p-value that says whether the list is more connected than chance). Each input is mapped first (gene symbol, UniProt accession, Ensembl protein ID or STRING ID); proteins shows how each mapped and inputs that matched nothing come back in unmapped with a warning. preferred_name is the gene symbol (join to genenames-org or gene-ncbi-nlm-nih-gov); the STRING ID embeds the Ensembl protein ID for human and most vertebrates (protein_id; join to uniprot-org proteins/map_ids). No proteins are added to the network. Also the STRING version, a link to the network on string-db.org and the CC BY 4.0 licence with attribution. - [Partners](https://firecrawl.dev/alexandria/agents/providers/string-db-org/interactions/partners): One protein's interaction partners in STRING for a species: each partner's gene symbol and STRING ID with the combined confidence score (0 to 1) and the seven evidence channel scores (neighborhood, gene_fusion, cooccurrence, coexpression, experiments, databases, text_mining), highest first. protein takes a gene symbol, UniProt accession, Ensembl protein ID or STRING ID and is mapped first; the answer shows how it mapped (STRING ID, preferred_name, annotation, species) and warns when STRING matched an alias or a similar name. preferred_name is the gene symbol (join to genenames-org or gene-ncbi-nlm-nih-gov by it); the STRING ID is the NCBI taxon plus a dot plus protein_id, the Ensembl protein ID for human and most vertebrates (join to uniprot-org proteins/map_ids). min_score takes STRING's bands (0.4 medium, 0.7 high, 0.9 highest); network_type physical keeps only binding and complex evidence. Also the STRING version, a link to the network on string-db.org and the CC BY 4.0 licence with the attribution STRING asks for. - [Enrichment](https://firecrawl.dev/alexandria/agents/providers/string-db-org/annotations/enrichment): Functional enrichment of a list of 2 to 200 proteins in one species against the whole genome, as STRING computes it: the terms the list is over-represented for, with the term's category, source database and licence, ID, name, how many of your proteins and how many genome proteins have it, p-value, FDR and which of your genes carry it. Categories are Gene Ontology (Process, Function, Component), UniProt Keywords, Reactome (RCTM), WikiPathways, MSigDB Hallmark, COMPARTMENTS, TISSUES, DISEASES, InterPro, Pfam, PubMed papers (PMID), STRING network clusters (NetworkNeighborAL) and Mammalian Phenotype (MPO). Categories whose source licence does not permit commercial redistribution (KEGG, SMART, the Human Phenotype Ontology) or is unverified are left out, and excluded_categories counts what was dropped and why; no term data from them is returned. Inputs are mapped first (gene symbol, UniProt accession, Ensembl protein ID or STRING ID; unmapped ones warn); genes lists preferred names, the gene symbols to join to genenames-org or gene-ncbi-nlm-nih-gov, and the STRING ID embeds the Ensembl protein ID (protein_id; join to uniprot-org proteins/map_ids). Also the STRING version, the licence of STRING (CC BY 4.0) and of every source database present. ## 1. Choose this provider when STRING (string-db.org, version 12.5; SIB, Novo Nordisk Foundation CPR and EMBL), the database of known and predicted protein-protein associations, through its public REST API (CC BY 4.0). Gives one protein's interaction partners or the network among a gene list in any of about 12,500 species, with STRING's combined confidence score and its seven evidence channels (neighborhood, gene fusion, co-occurrence, co-expression, experiments, curated databases, text mining), physical-only or functional associations, and the network's PPI enrichment p-value against chance. Runs functional enrichment of a gene list (Gene Ontology, Reactome, WikiPathways, UniProt keywords, Hallmark, COMPARTMENTS, TISSUES, DISEASES, InterPro, Pfam, PubMed, mammalian phenotypes) with FDR and the matched genes, limited to categories whose source licence permits commercial redistribution: KEGG, SMART and HPO terms are left out and counted. Names are mapped first (gene symbol, UniProt accession, Ensembl protein ID, STRING ID) and every answer names the STRING version, its licence and attribution. STRING (string-db.org, version 12.5; SIB, Novo Nordisk Foundation CPR and EMBL), the database of known and predicted protein-protein associations, through its public REST API (CC BY 4.0). Gives one protein's interaction partners or the network among a gene list in any of about 12,500 species, with STRING's combined confidence score and its seven evidence channels (neighborhood, gene fusion, co-occurrence, co-expression, experiments, curated databases, text mining), physical-only or functional associations, and the network's PPI enrichment p-value against chance. Runs functional enrichment of a gene list (Gene Ontology, Reactome, WikiPathways, UniProt keywords, Hallmark, COMPARTMENTS, TISSUES, DISEASES, InterPro, Pfam, PubMed, mammalian phenotypes) with FDR and the matched genes, limited to categories whose source licence permits commercial redistribution: KEGG, SMART and HPO terms are left out and counted. Names are mapped first (gene symbol, UniProt accession, Ensembl protein ID, STRING ID) and every answer names the STRING version, its licence and attribution. ## 2. Minimal request Call `POST https://api.firecrawl.dev/v2/scrape` with `{ alexandria: { provider, capability, options } }`. For a batch, send `{ alexandria: [...] }` with up to 10 calls. ```json { "provider": "string-db-org", "capability": "interactions/network", "options": { "min_score": 0.7, "proteins": [ "LDLR", "PCSK9", "APOB", "APOE", "LPL", "ABCA1", "LCAT", "CETP", "NPC1L1", "HMGCR" ], "species": 9606 } } ``` ## 3. Add provider options Use only the options needed for the task: - `min_score` (number): Minimum combined confidence score, 0 to 1. STRING's bands: 0.15 low, 0.4 medium (default), 0.7 high, 0.9 highest. Use 0.7 for 'high confidence'. Example: `0.4` - `network_type` (string): functional: any association (shared pathway or process, co-expression, text mining and physical binding). physical: only evidence that the proteins bind each other or are in one complex. Example: `functional` - `proteins` (string[], required): Between 2 and 100 different proteins, each a gene symbol (PCSK9, Trp53), UniProt accession (P04637), Ensembl protein ID (ENSP00000269305) or STRING ID (9606.ENSP00000269305). Pass one array item per protein. Example: `[]` - `species` (number): The organism: an NCBI taxon ID (9606 human, 10090 mouse, 10116 rat, 7955 zebrafish, 7227 fruit fly, 6239 C. elegans, 4932 baker's yeast, 3702 Arabidopsis, 511145 E. coli K-12; STRING covers about 12,500) or one of the names human, mouse, rat, zebrafish, fruit fly, worm, yeast, arabidopsis, e. coli, chicken, cow, pig, dog (or the Latin name). Defaults to human, or to the taxon of a STRING ID given as protein (10090.ENSMUSP00000104298 is mouse). Proteins are looked up in this species only. Example: `9606` ## 4. Request through your preferred interface ### JavaScript ```javascript const result = await firecrawl.scrape({ alexandria: { provider: "string-db-org", capability: "interactions/network", options: { min_score: 0.7, proteins: [ "LDLR", "PCSK9", "APOB", "APOE", "LPL", "ABCA1", "LCAT", "CETP", "NPC1L1", "HMGCR", ], species: 9606, }, }, }); ``` ### Python ```python result = firecrawl.scrape_alexandria({ "provider": "string-db-org", "capability": "interactions/network", "options": { "min_score": 0.7, "proteins": [ "LDLR", "PCSK9", "APOB", "APOE", "LPL", "ABCA1", "LCAT", "CETP", "NPC1L1", "HMGCR" ], "species": 9606 } }) ``` ### cURL ```sh curl https://api.firecrawl.dev/v2/scrape \ -H "Authorization: Bearer $FIRECRAWL_API_KEY" \ -H "Content-Type: application/json" \ -d '{ "alexandria": { "provider": "string-db-org", "capability": "interactions/network", "options": { "min_score": 0.7, "proteins": [ "LDLR", "PCSK9", "APOB", "APOE", "LPL", "ABCA1", "LCAT", "CETP", "NPC1L1", "HMGCR" ], "species": 9606 } } }' ``` ### CLI ```sh firecrawl scrape 'string-db-org/interactions/network' \ --options '{"min_score":0.7,"proteins":["LDLR","PCSK9","APOB","APOE","LPL","ABCA1","LCAT","CETP","NPC1L1","HMGCR"],"species":9606}' ``` ### MCP Call the FCX MCP retrieve tool with this object: ```json { "provider": "string-db-org", "capability": "interactions/network", "options": { "min_score": 0.7, "proteins": [ "LDLR", "PCSK9", "APOB", "APOE", "LPL", "ABCA1", "LCAT", "CETP", "NPC1L1", "HMGCR" ], "species": 9606 } } ``` Ask for only the returned fields needed by the task. ## 5. Full request shape ```json { "provider": "string-db-org", "capability": "interactions/network", "options": { "min_score": 0.7, "proteins": [ "LDLR", "PCSK9", "APOB", "APOE", "LPL", "ABCA1", "LCAT", "CETP", "NPC1L1", "HMGCR" ], "species": 9606 } } ``` ## 6. Response data The response includes `success`, `provider`, `capability`, `creditsCost` and `data`. This example shows the provider payload in `data`: ```json { "edge_count": 36, "edges": [ { "preferred_name_a": "APOB", "preferred_name_b": "LDLR", "scores": { "coexpression": 0.059, "combined": 0.999, "cooccurrence": 0, "databases": 0.9, "experiments": 0.923, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.959 }, "string_id_a": "9606.ENSP00000233242", "string_id_b": "9606.ENSP00000454071" }, { "preferred_name_a": "PCSK9", "preferred_name_b": "LDLR", "scores": { "coexpression": 0.101, "combined": 0.999, "cooccurrence": 0, "databases": 0.9, "experiments": 0.999, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.94 }, "string_id_a": "9606.ENSP00000303208", "string_id_b": "9606.ENSP00000454071" }, { "preferred_name_a": "APOB", "preferred_name_b": "APOE", "scores": { "coexpression": 0.223, "combined": 0.998, "cooccurrence": 0, "databases": 0.9, "experiments": 0.716, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.953 }, "string_id_a": "9606.ENSP00000233242", "string_id_b": "9606.ENSP00000252486" }, { "preferred_name_a": "APOE", "preferred_name_b": "LDLR", "scores": { "coexpression": 0, "combined": 0.998, "cooccurrence": 0, "databases": 0.5, "experiments": 0.953, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.953 }, "string_id_a": "9606.ENSP00000252486", "string_id_b": "9606.ENSP00000454071" }, { "preferred_name_a": "CETP", "preferred_name_b": "LCAT", "scores": { "coexpression": 0.219, "combined": 0.993, "cooccurrence": 0, "databases": 0.9, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.923 }, "string_id_a": "9606.ENSP00000200676", "string_id_b": "9606.ENSP00000264005" }, { "preferred_name_a": "CETP", "preferred_name_b": "APOE", "scores": { "coexpression": 0.065, "combined": 0.988, "cooccurrence": 0, "databases": 0.9, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.889 }, "string_id_a": "9606.ENSP00000200676", "string_id_b": "9606.ENSP00000252486" }, { "preferred_name_a": "CETP", "preferred_name_b": "APOB", "scores": { "coexpression": 0.093, "combined": 0.986, "cooccurrence": 0, "databases": 0.75, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.944 }, "string_id_a": "9606.ENSP00000200676", "string_id_b": "9606.ENSP00000233242" }, { "preferred_name_a": "APOE", "preferred_name_b": "LCAT", "scores": { "coexpression": 0.075, "combined": 0.981, "cooccurrence": 0, "databases": 0.9, "experiments": 0.457, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.675 }, "string_id_a": "9606.ENSP00000252486", "string_id_b": "9606.ENSP00000264005" }, { "preferred_name_a": "APOE", "preferred_name_b": "LPL", "scores": { "coexpression": 0.095, "combined": 0.969, "cooccurrence": 0, "databases": 0.8, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.845 }, "string_id_a": "9606.ENSP00000252486", "string_id_b": "9606.ENSP00000497642" }, { "preferred_name_a": "APOB", "preferred_name_b": "LCAT", "scores": { "coexpression": 0.114, "combined": 0.966, "cooccurrence": 0, "databases": 0.72, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.875 }, "string_id_a": "9606.ENSP00000233242", "string_id_b": "9606.ENSP00000264005" }, { "preferred_name_a": "APOB", "preferred_name_b": "PCSK9", "scores": { "coexpression": 0.141, "combined": 0.966, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.963 }, "string_id_a": "9606.ENSP00000233242", "string_id_b": "9606.ENSP00000303208" }, { "preferred_name_a": "CETP", "preferred_name_b": "LPL", "scores": { "coexpression": 0.069, "combined": 0.926, "cooccurrence": 0, "databases": 0.36, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.886 }, "string_id_a": "9606.ENSP00000200676", "string_id_b": "9606.ENSP00000497642" }, { "preferred_name_a": "HMGCR", "preferred_name_b": "LDLR", "scores": { "coexpression": 0.249, "combined": 0.924, "cooccurrence": 0, "databases": 0, "experiments": 0.09, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.898 }, "string_id_a": "9606.ENSP00000287936", "string_id_b": "9606.ENSP00000454071" }, { "preferred_name_a": "APOE", "preferred_name_b": "ABCA1", "scores": { "coexpression": 0.08, "combined": 0.918, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.915 }, "string_id_a": "9606.ENSP00000252486", "string_id_b": "9606.ENSP00000363868" }, { "preferred_name_a": "CETP", "preferred_name_b": "LDLR", "scores": { "coexpression": 0.059, "combined": 0.918, "cooccurrence": 0, "databases": 0.36, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.875 }, "string_id_a": "9606.ENSP00000200676", "string_id_b": "9606.ENSP00000454071" }, { "preferred_name_a": "APOB", "preferred_name_b": "LPL", "scores": { "coexpression": 0, "combined": 0.916, "cooccurrence": 0, "databases": 0.4, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.866 }, "string_id_a": "9606.ENSP00000233242", "string_id_b": "9606.ENSP00000497642" }, { "preferred_name_a": "HMGCR", "preferred_name_b": "PCSK9", "scores": { "coexpression": 0.128, "combined": 0.911, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.903 }, "string_id_a": "9606.ENSP00000287936", "string_id_b": "9606.ENSP00000303208" }, { "preferred_name_a": "HMGCR", "preferred_name_b": "NPC1L1", "scores": { "coexpression": 0.066, "combined": 0.906, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.904 }, "string_id_a": "9606.ENSP00000287936", "string_id_b": "9606.ENSP00000289547" }, { "preferred_name_a": "APOB", "preferred_name_b": "NPC1L1", "scores": { "coexpression": 0.095, "combined": 0.899, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.893 }, "string_id_a": "9606.ENSP00000233242", "string_id_b": "9606.ENSP00000289547" }, { "preferred_name_a": "APOB", "preferred_name_b": "HMGCR", "scores": { "coexpression": 0.069, "combined": 0.889, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.886 }, "string_id_a": "9606.ENSP00000233242", "string_id_b": "9606.ENSP00000287936" }, { "preferred_name_a": "LDLR", "preferred_name_b": "LPL", "scores": { "coexpression": 0.055, "combined": 0.875, "cooccurrence": 0, "databases": 0.36, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.811 }, "string_id_a": "9606.ENSP00000454071", "string_id_b": "9606.ENSP00000497642" }, { "preferred_name_a": "ABCA1", "preferred_name_b": "LDLR", "scores": { "coexpression": 0, "combined": 0.864, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.864 }, "string_id_a": "9606.ENSP00000363868", "string_id_b": "9606.ENSP00000454071" }, { "preferred_name_a": "LCAT", "preferred_name_b": "ABCA1", "scores": { "coexpression": 0.086, "combined": 0.856, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.849 }, "string_id_a": "9606.ENSP00000264005", "string_id_b": "9606.ENSP00000363868" }, { "preferred_name_a": "LCAT", "preferred_name_b": "LPL", "scores": { "coexpression": 0, "combined": 0.845, "cooccurrence": 0, "databases": 0.36, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.768 }, "string_id_a": "9606.ENSP00000264005", "string_id_b": "9606.ENSP00000497642" }, { "preferred_name_a": "CETP", "preferred_name_b": "ABCA1", "scores": { "coexpression": 0.044, "combined": 0.816, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.816 }, "string_id_a": "9606.ENSP00000200676", "string_id_b": "9606.ENSP00000363868" }, { "preferred_name_a": "NPC1L1", "preferred_name_b": "ABCA1", "scores": { "coexpression": 0, "combined": 0.804, "cooccurrence": 0, "databases": 0, "experiments": 0.069, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.799 }, "string_id_a": "9606.ENSP00000289547", "string_id_b": "9606.ENSP00000363868" }, { "preferred_name_a": "APOE", "preferred_name_b": "HMGCR", "scores": { "coexpression": 0, "combined": 0.797, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.797 }, "string_id_a": "9606.ENSP00000252486", "string_id_b": "9606.ENSP00000287936" }, { "preferred_name_a": "CETP", "preferred_name_b": "NPC1L1", "scores": { "coexpression": 0.058, "combined": 0.793, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.79 }, "string_id_a": "9606.ENSP00000200676", "string_id_b": "9606.ENSP00000289547" }, { "preferred_name_a": "CETP", "preferred_name_b": "PCSK9", "scores": { "coexpression": 0, "combined": 0.776, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.776 }, "string_id_a": "9606.ENSP00000200676", "string_id_b": "9606.ENSP00000303208" }, { "preferred_name_a": "LCAT", "preferred_name_b": "LDLR", "scores": { "coexpression": 0, "combined": 0.775, "cooccurrence": 0, "databases": 0.36, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.663 }, "string_id_a": "9606.ENSP00000264005", "string_id_b": "9606.ENSP00000454071" }, { "preferred_name_a": "APOB", "preferred_name_b": "ABCA1", "scores": { "coexpression": 0, "combined": 0.774, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.774 }, "string_id_a": "9606.ENSP00000233242", "string_id_b": "9606.ENSP00000363868" }, { "preferred_name_a": "CETP", "preferred_name_b": "HMGCR", "scores": { "coexpression": 0, "combined": 0.774, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.774 }, "string_id_a": "9606.ENSP00000200676", "string_id_b": "9606.ENSP00000287936" }, { "preferred_name_a": "HMGCR", "preferred_name_b": "ABCA1", "scores": { "coexpression": 0, "combined": 0.774, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.774 }, "string_id_a": "9606.ENSP00000287936", "string_id_b": "9606.ENSP00000363868" }, { "preferred_name_a": "APOE", "preferred_name_b": "PCSK9", "scores": { "coexpression": 0.075, "combined": 0.746, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.737 }, "string_id_a": "9606.ENSP00000252486", "string_id_b": "9606.ENSP00000303208" }, { "preferred_name_a": "NPC1L1", "preferred_name_b": "PCSK9", "scores": { "coexpression": 0, "combined": 0.744, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.744 }, "string_id_a": "9606.ENSP00000289547", "string_id_b": "9606.ENSP00000303208" }, { "preferred_name_a": "NPC1L1", "preferred_name_b": "LDLR", "scores": { "coexpression": 0, "combined": 0.715, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.715 }, "string_id_a": "9606.ENSP00000289547", "string_id_b": "9606.ENSP00000454071" } ], "license": { "attribution": "STRING v12.5 (https://string-db.org), STRING Consortium; Szklarczyk D, et al. The STRING database in 2025: protein networks with directionality of regulation. Nucleic Acids Res. 2025;53(D1):D730-D737.", "changes": "Reformatted by Firecrawl: field names changed, the seven evidence channels named, results sorted and cut to the requested limit. STRING's scores and statistics are unchanged.", "name": "CC BY 4.0", "url": "https://creativecommons.org/licenses/by/4.0/" }, "min_score": 0.7, "network_type": "functional", "observed_at_ms": 1793394903878, "proteins": [ { "annotation": "Low-density lipoprotein receptor; Binds LDL, the major cholesterol-carrying lipoprotein of plasma, and transports it into cells by endocytosis. In order to be internalized, the receptor-ligand complexes must first cluster into clathrin-coated pits. (Microbial infection) Acts as a receptor for Vesicular stomatitis virus; Belongs to the LDLR family.", "inputs": [ "LDLR" ], "preferred_name": "LDLR", "protein_id": "ENSP00000454071", "string_id": "9606.ENSP00000454071" }, { "annotation": "Proprotein convertase subtilisin/kexin type 9; Crucial player in the regulation of plasma cholesterol homeostasis. Binds to low-density lipid receptor family members: low density lipoprotein receptor (LDLR), very low density lipoprotein receptor (VLDLR), apolipoprotein E receptor (LRP1/APOER) and apolipoprotein receptor 2 (LRP8/APOER2), and promotes their degradation in intracellular acidic compartments. Acts via a non- proteolytic mechanism to enhance the degradation of the hepatic LDLR through a clathrin LDLRAP1/ARH-mediated pathway. May prevent the recycling of LDLR from endosomes t [...] ", "inputs": [ "PCSK9" ], "preferred_name": "PCSK9", "protein_id": "ENSP00000303208", "string_id": "9606.ENSP00000303208" }, { "annotation": "Apolipoprotein B-100; Apolipoprotein B is a major protein constituent of chylomicrons (apo B-48), LDL (apo B-100) and VLDL (apo B-100). Apo B- 100 functions as a recognition signal for the cellular binding and internalization of LDL particles by the apoB/E receptor.", "inputs": [ "APOB" ], "preferred_name": "APOB", "protein_id": "ENSP00000233242", "string_id": "9606.ENSP00000233242" }, { "annotation": "Apolipoprotein E; APOE is an apolipoprotein, a protein associating with lipid particles, that mainly functions in lipoprotein-mediated lipid transport between organs via the plasma and interstitial fluids. APOE is a core component of plasma lipoproteins and is involved in their production, conversion and clearance. Apoliproteins are amphipathic molecules that interact both with lipids of the lipoprotein particle core and the aqueous environment of the plasma. As such, APOE associates with chylomicrons, chylomicron remnants, very low density lipoproteins (VLDL) and intermediate density [...] ", "inputs": [ "APOE" ], "preferred_name": "APOE", "protein_id": "ENSP00000252486", "string_id": "9606.ENSP00000252486" }, { "annotation": "Lipoprotein lipase; Key enzyme in triglyceride metabolism. Catalyzes the hydrolysis of triglycerides from circulating chylomicrons and very low density lipoproteins (VLDL), and thereby plays an important role in lipid clearance from the blood stream, lipid utilization and storage. Mediates margination of triglyceride-rich lipoprotein particles in capillaries. Recruited to its site of action on the luminal surface of vascular endothelium by binding to GPIHBP1 and cell surface heparan sulfate proteoglycans.", "inputs": [ "LPL" ], "preferred_name": "LPL", "protein_id": "ENSP00000497642", "string_id": "9606.ENSP00000497642" }, { "annotation": "Phospholipid-transporting ATPase ABCA1; Catalyzes the translocation of specific phospholipids from the cytoplasmic to the extracellular/lumenal leaflet of membrane coupled to the hydrolysis of ATP. Thereby, participates to phospholipids transfer to apoliproteins to form nascent high density lipoproteins/HDLs. Transports preferentially phosphatidylcholine over phosphatidylserine. May play a similar role in the efflux of intracellular cholesterol to apoliproteins and the formation of nascent high density lipoproteins/HDLs ; Belongs to the ABC transporter superfamily. ABCA family.", "inputs": [ "ABCA1" ], "preferred_name": "ABCA1", "protein_id": "ENSP00000363868", "string_id": "9606.ENSP00000363868" }, { "annotation": "Phosphatidylcholine-sterol acyltransferase; Central enzyme in the extracellular metabolism of plasma lipoproteins. Synthesized mainly in the liver and secreted into plasma where it converts cholesterol and phosphatidylcholines (lecithins) to cholesteryl esters and lysophosphatidylcholines on the surface of high and low density lipoproteins (HDLs and LDLs). The cholesterol ester is then transported back to the liver. Has a preference for plasma 16:0-18:2 or 18:O-18:2 phosphatidylcholines. Also produced in the brain by primary astrocytes, and esterifies free cholesterol on nascent APOE-c [...] ", "inputs": [ "LCAT" ], "preferred_name": "LCAT", "protein_id": "ENSP00000264005", "string_id": "9606.ENSP00000264005" }, { "annotation": "Cholesteryl ester transfer protein; Involved in the transfer of neutral lipids, including cholesteryl ester and triglyceride, among lipoprotein particles. Allows the net movement of cholesteryl ester from high density lipoproteins/HDL to triglyceride-rich very low density lipoproteins/VLDL, and the equimolar transport of triglyceride from VLDL to HDL. Regulates the reverse cholesterol transport, by which excess cholesterol is removed from peripheral tissues and returned to the liver for elimination ; Belongs to the BPI/LBP/Plunc superfamily. BPI/LBP family.", "inputs": [ "CETP" ], "preferred_name": "CETP", "protein_id": "ENSP00000200676", "string_id": "9606.ENSP00000200676" }, { "annotation": "NPC1-like intracellular cholesterol transporter 1; Plays a major role in cholesterol homeostasis. Is critical for the uptake of cholesterol across the plasma membrane of the intestinal enterocyte. Is the direct molecular target of ezetimibe, a drug that inhibits cholesterol absorption. Lack of activity leads to multiple lipid transport defects. The protein may have a function in the transport of multiple lipids and their homeostasis, and may play a critical role in regulating lipid metabolism. Acts as a negative regulator of NPC2 and down-regulates its expression and secretion by inhib [...] ", "inputs": [ "NPC1L1" ], "preferred_name": "NPC1L1", "protein_id": "ENSP00000289547", "string_id": "9606.ENSP00000289547" }, { "annotation": "3-hydroxy-3-methylglutaryl-coenzyme A reductase; Transmembrane glycoprotein that is the rate-limiting enzyme in cholesterol biosynthesis as well as in the biosynthesis of nonsterol isoprenoids that are essential for normal cell function including ubiquinone and geranylgeranyl proteins.", "inputs": [ "HMGCR" ], "preferred_name": "HMGCR", "protein_id": "ENSP00000287936", "string_id": "9606.ENSP00000287936" } ], "source_url": "https://version-12-5.string-db.org/cgi/network?identifiers=9606.ENSP00000454071%0D9606.ENSP00000303208%0D9606.ENSP00000233242%0D9606.ENSP00000252486%0D9606.ENSP00000497642%0D9606.ENSP00000363868%0D9606.ENSP00000264005%0D9606.ENSP00000200676%0D9606.ENSP00000289547%0D9606.ENSP00000287936&species=9606&required_score=700&network_type=functional", "species": { "name": "Homo sapiens", "taxon_id": 9606 }, "statistics": { "average_node_degree": 7.2, "edges": 36, "expected_edges": 0, "local_clustering_coefficient": 0.86, "nodes": 10, "ppi_enrichment_p_value": 4.73e-62 }, "string_version": "12.5", "unmapped": [] } ``` ## API reference-derived contract The following capability contract is generated from the same normalized Alexandria API reference exposed in the API spec. ### Network - Capability: `interactions/network` - Description: The interaction network among a list of 2 to 100 proteins in one species: every pair STRING scores at or above min_score, with the combined confidence score and the seven evidence channel scores, plus STRING's network statistics (nodes, edges against the number expected for random proteins, average node degree, clustering coefficient and the PPI enrichment p-value that says whether the list is more connected than chance). Each input is mapped first (gene symbol, UniProt accession, Ensembl protein ID or STRING ID); proteins shows how each mapped and inputs that matched nothing come back in unmapped with a warning. preferred_name is the gene symbol (join to genenames-org or gene-ncbi-nlm-nih-gov); the STRING ID embeds the Ensembl protein ID for human and most vertebrates (protein_id; join to uniprot-org proteins/map_ids). No proteins are added to the network. Also the STRING version, a link to the network on string-db.org and the CC BY 4.0 licence with attribution. - Instructions: How a set of genes or proteins you already have connect to each other, and whether they are more connected than chance (PPI enrichment p-value): a candidate list, a screen hit list, the members of a complex. For one protein's partners (including ones not in your list) use partners; for the functions and pathways the list shares use enrichment (or reactome-org for Reactome pathways only). Needs at least 2 different proteins that map in one species. Edges are associations of every evidence type unless network_type is physical. - Cost: 5 credits per call - Capability file: [Network](https://firecrawl.dev/alexandria/agents/providers/string-db-org/interactions/network) Accepted options: - `min_score` (number): Minimum combined confidence score, 0 to 1. STRING's bands: 0.15 low, 0.4 medium (default), 0.7 high, 0.9 highest. Use 0.7 for 'high confidence'. Example: `0.4` - `network_type` (string): functional: any association (shared pathway or process, co-expression, text mining and physical binding). physical: only evidence that the proteins bind each other or are in one complex. Example: `functional` - `proteins` (string[], required): Between 2 and 100 different proteins, each a gene symbol (PCSK9, Trp53), UniProt accession (P04637), Ensembl protein ID (ENSP00000269305) or STRING ID (9606.ENSP00000269305). Pass one array item per protein. Example: `[]` - `species` (number): The organism: an NCBI taxon ID (9606 human, 10090 mouse, 10116 rat, 7955 zebrafish, 7227 fruit fly, 6239 C. elegans, 4932 baker's yeast, 3702 Arabidopsis, 511145 E. coli K-12; STRING covers about 12,500) or one of the names human, mouse, rat, zebrafish, fruit fly, worm, yeast, arabidopsis, e. coli, chicken, cow, pig, dog (or the Latin name). Defaults to human, or to the taxon of a STRING ID given as protein (10090.ENSMUSP00000104298 is mouse). Proteins are looked up in this species only. Example: `9606` Response schema example: ```json { "edge_count": 36, "edges": [ { "preferred_name_a": "APOB", "preferred_name_b": "LDLR", "scores": { "coexpression": 0.059, "combined": 0.999, "cooccurrence": 0, "databases": 0.9, "experiments": 0.923, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.959 }, "string_id_a": "9606.ENSP00000233242", "string_id_b": "9606.ENSP00000454071" }, { "preferred_name_a": "PCSK9", "preferred_name_b": "LDLR", "scores": { "coexpression": 0.101, "combined": 0.999, "cooccurrence": 0, "databases": 0.9, "experiments": 0.999, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.94 }, "string_id_a": "9606.ENSP00000303208", "string_id_b": "9606.ENSP00000454071" }, { "preferred_name_a": "APOB", "preferred_name_b": "APOE", "scores": { "coexpression": 0.223, "combined": 0.998, "cooccurrence": 0, "databases": 0.9, "experiments": 0.716, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.953 }, "string_id_a": "9606.ENSP00000233242", "string_id_b": "9606.ENSP00000252486" }, { "preferred_name_a": "APOE", "preferred_name_b": "LDLR", "scores": { "coexpression": 0, "combined": 0.998, "cooccurrence": 0, "databases": 0.5, "experiments": 0.953, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.953 }, "string_id_a": "9606.ENSP00000252486", "string_id_b": "9606.ENSP00000454071" }, { "preferred_name_a": "CETP", "preferred_name_b": "LCAT", "scores": { "coexpression": 0.219, "combined": 0.993, "cooccurrence": 0, "databases": 0.9, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.923 }, "string_id_a": "9606.ENSP00000200676", "string_id_b": "9606.ENSP00000264005" }, { "preferred_name_a": "CETP", "preferred_name_b": "APOE", "scores": { "coexpression": 0.065, "combined": 0.988, "cooccurrence": 0, "databases": 0.9, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.889 }, "string_id_a": "9606.ENSP00000200676", "string_id_b": "9606.ENSP00000252486" }, { "preferred_name_a": "CETP", "preferred_name_b": "APOB", "scores": { "coexpression": 0.093, "combined": 0.986, "cooccurrence": 0, "databases": 0.75, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.944 }, "string_id_a": "9606.ENSP00000200676", "string_id_b": "9606.ENSP00000233242" }, { "preferred_name_a": "APOE", "preferred_name_b": "LCAT", "scores": { "coexpression": 0.075, "combined": 0.981, "cooccurrence": 0, "databases": 0.9, "experiments": 0.457, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.675 }, "string_id_a": "9606.ENSP00000252486", "string_id_b": "9606.ENSP00000264005" }, { "preferred_name_a": "APOE", "preferred_name_b": "LPL", "scores": { "coexpression": 0.095, "combined": 0.969, "cooccurrence": 0, "databases": 0.8, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.845 }, "string_id_a": "9606.ENSP00000252486", "string_id_b": "9606.ENSP00000497642" }, { "preferred_name_a": "APOB", "preferred_name_b": "LCAT", "scores": { "coexpression": 0.114, "combined": 0.966, "cooccurrence": 0, "databases": 0.72, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.875 }, "string_id_a": "9606.ENSP00000233242", "string_id_b": "9606.ENSP00000264005" }, { "preferred_name_a": "APOB", "preferred_name_b": "PCSK9", "scores": { "coexpression": 0.141, "combined": 0.966, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.963 }, "string_id_a": "9606.ENSP00000233242", "string_id_b": "9606.ENSP00000303208" }, { "preferred_name_a": "CETP", "preferred_name_b": "LPL", "scores": { "coexpression": 0.069, "combined": 0.926, "cooccurrence": 0, "databases": 0.36, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.886 }, "string_id_a": "9606.ENSP00000200676", "string_id_b": "9606.ENSP00000497642" }, { "preferred_name_a": "HMGCR", "preferred_name_b": "LDLR", "scores": { "coexpression": 0.249, "combined": 0.924, "cooccurrence": 0, "databases": 0, "experiments": 0.09, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.898 }, "string_id_a": "9606.ENSP00000287936", "string_id_b": "9606.ENSP00000454071" }, { "preferred_name_a": "APOE", "preferred_name_b": "ABCA1", "scores": { "coexpression": 0.08, "combined": 0.918, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.915 }, "string_id_a": "9606.ENSP00000252486", "string_id_b": "9606.ENSP00000363868" }, { "preferred_name_a": "CETP", "preferred_name_b": "LDLR", "scores": { "coexpression": 0.059, "combined": 0.918, "cooccurrence": 0, "databases": 0.36, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.875 }, "string_id_a": "9606.ENSP00000200676", "string_id_b": "9606.ENSP00000454071" }, { "preferred_name_a": "APOB", "preferred_name_b": "LPL", "scores": { "coexpression": 0, "combined": 0.916, "cooccurrence": 0, "databases": 0.4, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.866 }, "string_id_a": "9606.ENSP00000233242", "string_id_b": "9606.ENSP00000497642" }, { "preferred_name_a": "HMGCR", "preferred_name_b": "PCSK9", "scores": { "coexpression": 0.128, "combined": 0.911, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.903 }, "string_id_a": "9606.ENSP00000287936", "string_id_b": "9606.ENSP00000303208" }, { "preferred_name_a": "HMGCR", "preferred_name_b": "NPC1L1", "scores": { "coexpression": 0.066, "combined": 0.906, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.904 }, "string_id_a": "9606.ENSP00000287936", "string_id_b": "9606.ENSP00000289547" }, { "preferred_name_a": "APOB", "preferred_name_b": "NPC1L1", "scores": { "coexpression": 0.095, "combined": 0.899, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.893 }, "string_id_a": "9606.ENSP00000233242", "string_id_b": "9606.ENSP00000289547" }, { "preferred_name_a": "APOB", "preferred_name_b": "HMGCR", "scores": { "coexpression": 0.069, "combined": 0.889, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.886 }, "string_id_a": "9606.ENSP00000233242", "string_id_b": "9606.ENSP00000287936" }, { "preferred_name_a": "LDLR", "preferred_name_b": "LPL", "scores": { "coexpression": 0.055, "combined": 0.875, "cooccurrence": 0, "databases": 0.36, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.811 }, "string_id_a": "9606.ENSP00000454071", "string_id_b": "9606.ENSP00000497642" }, { "preferred_name_a": "ABCA1", "preferred_name_b": "LDLR", "scores": { "coexpression": 0, "combined": 0.864, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.864 }, "string_id_a": "9606.ENSP00000363868", "string_id_b": "9606.ENSP00000454071" }, { "preferred_name_a": "LCAT", "preferred_name_b": "ABCA1", "scores": { "coexpression": 0.086, "combined": 0.856, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.849 }, "string_id_a": "9606.ENSP00000264005", "string_id_b": "9606.ENSP00000363868" }, { "preferred_name_a": "LCAT", "preferred_name_b": "LPL", "scores": { "coexpression": 0, "combined": 0.845, "cooccurrence": 0, "databases": 0.36, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.768 }, "string_id_a": "9606.ENSP00000264005", "string_id_b": "9606.ENSP00000497642" }, { "preferred_name_a": "CETP", "preferred_name_b": "ABCA1", "scores": { "coexpression": 0.044, "combined": 0.816, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.816 }, "string_id_a": "9606.ENSP00000200676", "string_id_b": "9606.ENSP00000363868" }, { "preferred_name_a": "NPC1L1", "preferred_name_b": "ABCA1", "scores": { "coexpression": 0, "combined": 0.804, "cooccurrence": 0, "databases": 0, "experiments": 0.069, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.799 }, "string_id_a": "9606.ENSP00000289547", "string_id_b": "9606.ENSP00000363868" }, { "preferred_name_a": "APOE", "preferred_name_b": "HMGCR", "scores": { "coexpression": 0, "combined": 0.797, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.797 }, "string_id_a": "9606.ENSP00000252486", "string_id_b": "9606.ENSP00000287936" }, { "preferred_name_a": "CETP", "preferred_name_b": "NPC1L1", "scores": { "coexpression": 0.058, "combined": 0.793, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.79 }, "string_id_a": "9606.ENSP00000200676", "string_id_b": "9606.ENSP00000289547" }, { "preferred_name_a": "CETP", "preferred_name_b": "PCSK9", "scores": { "coexpression": 0, "combined": 0.776, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.776 }, "string_id_a": "9606.ENSP00000200676", "string_id_b": "9606.ENSP00000303208" }, { "preferred_name_a": "LCAT", "preferred_name_b": "LDLR", "scores": { "coexpression": 0, "combined": 0.775, "cooccurrence": 0, "databases": 0.36, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.663 }, "string_id_a": "9606.ENSP00000264005", "string_id_b": "9606.ENSP00000454071" }, { "preferred_name_a": "APOB", "preferred_name_b": "ABCA1", "scores": { "coexpression": 0, "combined": 0.774, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.774 }, "string_id_a": "9606.ENSP00000233242", "string_id_b": "9606.ENSP00000363868" }, { "preferred_name_a": "CETP", "preferred_name_b": "HMGCR", "scores": { "coexpression": 0, "combined": 0.774, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.774 }, "string_id_a": "9606.ENSP00000200676", "string_id_b": "9606.ENSP00000287936" }, { "preferred_name_a": "HMGCR", "preferred_name_b": "ABCA1", "scores": { "coexpression": 0, "combined": 0.774, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.774 }, "string_id_a": "9606.ENSP00000287936", "string_id_b": "9606.ENSP00000363868" }, { "preferred_name_a": "APOE", "preferred_name_b": "PCSK9", "scores": { "coexpression": 0.075, "combined": 0.746, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.737 }, "string_id_a": "9606.ENSP00000252486", "string_id_b": "9606.ENSP00000303208" }, { "preferred_name_a": "NPC1L1", "preferred_name_b": "PCSK9", "scores": { "coexpression": 0, "combined": 0.744, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.744 }, "string_id_a": "9606.ENSP00000289547", "string_id_b": "9606.ENSP00000303208" }, { "preferred_name_a": "NPC1L1", "preferred_name_b": "LDLR", "scores": { "coexpression": 0, "combined": 0.715, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.715 }, "string_id_a": "9606.ENSP00000289547", "string_id_b": "9606.ENSP00000454071" } ], "license": { "attribution": "STRING v12.5 (https://string-db.org), STRING Consortium; Szklarczyk D, et al. The STRING database in 2025: protein networks with directionality of regulation. Nucleic Acids Res. 2025;53(D1):D730-D737.", "changes": "Reformatted by Firecrawl: field names changed, the seven evidence channels named, results sorted and cut to the requested limit. STRING's scores and statistics are unchanged.", "name": "CC BY 4.0", "url": "https://creativecommons.org/licenses/by/4.0/" }, "min_score": 0.7, "network_type": "functional", "observed_at_ms": 1793394903878, "proteins": [ { "annotation": "Low-density lipoprotein receptor; Binds LDL, the major cholesterol-carrying lipoprotein of plasma, and transports it into cells by endocytosis. In order to be internalized, the receptor-ligand complexes must first cluster into clathrin-coated pits. (Microbial infection) Acts as a receptor for Vesicular stomatitis virus; Belongs to the LDLR family.", "inputs": [ "LDLR" ], "preferred_name": "LDLR", "protein_id": "ENSP00000454071", "string_id": "9606.ENSP00000454071" }, { "annotation": "Proprotein convertase subtilisin/kexin type 9; Crucial player in the regulation of plasma cholesterol homeostasis. Binds to low-density lipid receptor family members: low density lipoprotein receptor (LDLR), very low density lipoprotein receptor (VLDLR), apolipoprotein E receptor (LRP1/APOER) and apolipoprotein receptor 2 (LRP8/APOER2), and promotes their degradation in intracellular acidic compartments. Acts via a non- proteolytic mechanism to enhance the degradation of the hepatic LDLR through a clathrin LDLRAP1/ARH-mediated pathway. May prevent the recycling of LDLR from endosomes t [...] ", "inputs": [ "PCSK9" ], "preferred_name": "PCSK9", "protein_id": "ENSP00000303208", "string_id": "9606.ENSP00000303208" }, { "annotation": "Apolipoprotein B-100; Apolipoprotein B is a major protein constituent of chylomicrons (apo B-48), LDL (apo B-100) and VLDL (apo B-100). Apo B- 100 functions as a recognition signal for the cellular binding and internalization of LDL particles by the apoB/E receptor.", "inputs": [ "APOB" ], "preferred_name": "APOB", "protein_id": "ENSP00000233242", "string_id": "9606.ENSP00000233242" }, { "annotation": "Apolipoprotein E; APOE is an apolipoprotein, a protein associating with lipid particles, that mainly functions in lipoprotein-mediated lipid transport between organs via the plasma and interstitial fluids. APOE is a core component of plasma lipoproteins and is involved in their production, conversion and clearance. Apoliproteins are amphipathic molecules that interact both with lipids of the lipoprotein particle core and the aqueous environment of the plasma. As such, APOE associates with chylomicrons, chylomicron remnants, very low density lipoproteins (VLDL) and intermediate density [...] ", "inputs": [ "APOE" ], "preferred_name": "APOE", "protein_id": "ENSP00000252486", "string_id": "9606.ENSP00000252486" }, { "annotation": "Lipoprotein lipase; Key enzyme in triglyceride metabolism. Catalyzes the hydrolysis of triglycerides from circulating chylomicrons and very low density lipoproteins (VLDL), and thereby plays an important role in lipid clearance from the blood stream, lipid utilization and storage. Mediates margination of triglyceride-rich lipoprotein particles in capillaries. Recruited to its site of action on the luminal surface of vascular endothelium by binding to GPIHBP1 and cell surface heparan sulfate proteoglycans.", "inputs": [ "LPL" ], "preferred_name": "LPL", "protein_id": "ENSP00000497642", "string_id": "9606.ENSP00000497642" }, { "annotation": "Phospholipid-transporting ATPase ABCA1; Catalyzes the translocation of specific phospholipids from the cytoplasmic to the extracellular/lumenal leaflet of membrane coupled to the hydrolysis of ATP. Thereby, participates to phospholipids transfer to apoliproteins to form nascent high density lipoproteins/HDLs. Transports preferentially phosphatidylcholine over phosphatidylserine. May play a similar role in the efflux of intracellular cholesterol to apoliproteins and the formation of nascent high density lipoproteins/HDLs ; Belongs to the ABC transporter superfamily. ABCA family.", "inputs": [ "ABCA1" ], "preferred_name": "ABCA1", "protein_id": "ENSP00000363868", "string_id": "9606.ENSP00000363868" }, { "annotation": "Phosphatidylcholine-sterol acyltransferase; Central enzyme in the extracellular metabolism of plasma lipoproteins. Synthesized mainly in the liver and secreted into plasma where it converts cholesterol and phosphatidylcholines (lecithins) to cholesteryl esters and lysophosphatidylcholines on the surface of high and low density lipoproteins (HDLs and LDLs). The cholesterol ester is then transported back to the liver. Has a preference for plasma 16:0-18:2 or 18:O-18:2 phosphatidylcholines. Also produced in the brain by primary astrocytes, and esterifies free cholesterol on nascent APOE-c [...] ", "inputs": [ "LCAT" ], "preferred_name": "LCAT", "protein_id": "ENSP00000264005", "string_id": "9606.ENSP00000264005" }, { "annotation": "Cholesteryl ester transfer protein; Involved in the transfer of neutral lipids, including cholesteryl ester and triglyceride, among lipoprotein particles. Allows the net movement of cholesteryl ester from high density lipoproteins/HDL to triglyceride-rich very low density lipoproteins/VLDL, and the equimolar transport of triglyceride from VLDL to HDL. Regulates the reverse cholesterol transport, by which excess cholesterol is removed from peripheral tissues and returned to the liver for elimination ; Belongs to the BPI/LBP/Plunc superfamily. BPI/LBP family.", "inputs": [ "CETP" ], "preferred_name": "CETP", "protein_id": "ENSP00000200676", "string_id": "9606.ENSP00000200676" }, { "annotation": "NPC1-like intracellular cholesterol transporter 1; Plays a major role in cholesterol homeostasis. Is critical for the uptake of cholesterol across the plasma membrane of the intestinal enterocyte. Is the direct molecular target of ezetimibe, a drug that inhibits cholesterol absorption. Lack of activity leads to multiple lipid transport defects. The protein may have a function in the transport of multiple lipids and their homeostasis, and may play a critical role in regulating lipid metabolism. Acts as a negative regulator of NPC2 and down-regulates its expression and secretion by inhib [...] ", "inputs": [ "NPC1L1" ], "preferred_name": "NPC1L1", "protein_id": "ENSP00000289547", "string_id": "9606.ENSP00000289547" }, { "annotation": "3-hydroxy-3-methylglutaryl-coenzyme A reductase; Transmembrane glycoprotein that is the rate-limiting enzyme in cholesterol biosynthesis as well as in the biosynthesis of nonsterol isoprenoids that are essential for normal cell function including ubiquinone and geranylgeranyl proteins.", "inputs": [ "HMGCR" ], "preferred_name": "HMGCR", "protein_id": "ENSP00000287936", "string_id": "9606.ENSP00000287936" } ], "source_url": "https://version-12-5.string-db.org/cgi/network?identifiers=9606.ENSP00000454071%0D9606.ENSP00000303208%0D9606.ENSP00000233242%0D9606.ENSP00000252486%0D9606.ENSP00000497642%0D9606.ENSP00000363868%0D9606.ENSP00000264005%0D9606.ENSP00000200676%0D9606.ENSP00000289547%0D9606.ENSP00000287936&species=9606&required_score=700&network_type=functional", "species": { "name": "Homo sapiens", "taxon_id": 9606 }, "statistics": { "average_node_degree": 7.2, "edges": 36, "expected_edges": 0, "local_clustering_coefficient": 0.86, "nodes": 10, "ppi_enrichment_p_value": 4.73e-62 }, "string_version": "12.5", "unmapped": [] } ``` ### Partners - Capability: `interactions/partners` - Description: One protein's interaction partners in STRING for a species: each partner's gene symbol and STRING ID with the combined confidence score (0 to 1) and the seven evidence channel scores (neighborhood, gene_fusion, cooccurrence, coexpression, experiments, databases, text_mining), highest first. protein takes a gene symbol, UniProt accession, Ensembl protein ID or STRING ID and is mapped first; the answer shows how it mapped (STRING ID, preferred_name, annotation, species) and warns when STRING matched an alias or a similar name. preferred_name is the gene symbol (join to genenames-org or gene-ncbi-nlm-nih-gov by it); the STRING ID is the NCBI taxon plus a dot plus protein_id, the Ensembl protein ID for human and most vertebrates (join to uniprot-org proteins/map_ids). min_score takes STRING's bands (0.4 medium, 0.7 high, 0.9 highest); network_type physical keeps only binding and complex evidence. Also the STRING version, a link to the network on string-db.org and the CC BY 4.0 licence with the attribution STRING asks for. - Instructions: What interacts with one protein, and with what kind of evidence: 'STRING partners of PCSK9 above 0.7', 'physical partners of TP53', 'which partners of X have experimental evidence' (look at scores.experiments). For the links among several genes you already have use network; for what a gene list has in common (GO, pathways, diseases) use enrichment; for one protein's pathway memberships or reactions use reactome-org. To identify a gene or protein first (symbol, aliases, accession) use genenames-org, gene-ncbi-nlm-nih-gov or uniprot-org; STRING accepts their identifiers. Scores are evidence of association, not proof of direct binding. - Cost: 5 credits per call - Capability file: [Partners](https://firecrawl.dev/alexandria/agents/providers/string-db-org/interactions/partners) Accepted options: - `limit` (number): Most partners to return, best first. limit_reached tells whether there are more. Example: `20` - `min_score` (number): Minimum combined confidence score, 0 to 1. STRING's bands: 0.15 low, 0.4 medium (default), 0.7 high, 0.9 highest. Use 0.7 for 'high confidence'. Example: `0.4` - `network_type` (string): functional: any association (shared pathway or process, co-expression, text mining and physical binding). physical: only evidence that the proteins bind each other or are in one complex. Example: `functional` - `protein` (string, required): A gene symbol (PCSK9, Trp53), UniProt accession (P04637), Ensembl protein ID (ENSP00000269305) or STRING ID (9606.ENSP00000269305). Gene symbols and aliases are matched loosely (p53 finds TP53), so check preferred_name in the answer; use the species' own symbol or an accession for an exact match. Example: `` - `species` (number): The organism: an NCBI taxon ID (9606 human, 10090 mouse, 10116 rat, 7955 zebrafish, 7227 fruit fly, 6239 C. elegans, 4932 baker's yeast, 3702 Arabidopsis, 511145 E. coli K-12; STRING covers about 12,500) or one of the names human, mouse, rat, zebrafish, fruit fly, worm, yeast, arabidopsis, e. coli, chicken, cow, pig, dog (or the Latin name). Defaults to human, or to the taxon of a STRING ID given as protein (10090.ENSMUSP00000104298 is mouse). Proteins are looked up in this species only. Example: `9606` Response schema example: ```json { "license": { "attribution": "STRING v12.5 (https://string-db.org), STRING Consortium; Szklarczyk D, et al. The STRING database in 2025: protein networks with directionality of regulation. Nucleic Acids Res. 2025;53(D1):D730-D737.", "changes": "Reformatted by Firecrawl: field names changed, the seven evidence channels named, results sorted and cut to the requested limit. STRING's scores and statistics are unchanged.", "name": "CC BY 4.0", "url": "https://creativecommons.org/licenses/by/4.0/" }, "limit": 10, "limit_reached": true, "min_score": 0.7, "network_type": "functional", "observed_at_ms": 1793394903873, "partner_count": 10, "partners": [ { "preferred_name": "LDLR", "protein_id": "ENSP00000454071", "scores": { "coexpression": 0.101, "combined": 0.999, "cooccurrence": 0, "databases": 0.9, "experiments": 0.999, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.94 }, "string_id": "9606.ENSP00000454071" }, { "preferred_name": "APOB", "protein_id": "ENSP00000233242", "scores": { "coexpression": 0.141, "combined": 0.966, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.963 }, "string_id": "9606.ENSP00000233242" }, { "preferred_name": "ANXA2", "protein_id": "ENSP00000346032", "scores": { "coexpression": 0, "combined": 0.957, "cooccurrence": 0, "databases": 0.9, "experiments": 0.456, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.287 }, "string_id": "9606.ENSP00000346032" }, { "preferred_name": "VLDLR", "protein_id": "ENSP00000371532", "scores": { "coexpression": 0.059, "combined": 0.956, "cooccurrence": 0, "databases": 0.9, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.576 }, "string_id": "9606.ENSP00000371532" }, { "preferred_name": "FAM20C", "protein_id": "ENSP00000322323", "scores": { "coexpression": 0.065, "combined": 0.916, "cooccurrence": 0, "databases": 0.5, "experiments": 0.802, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.203 }, "string_id": "9606.ENSP00000322323" }, { "preferred_name": "SREBF2", "protein_id": "ENSP00000354476", "scores": { "coexpression": 0.097, "combined": 0.912, "cooccurrence": 0, "databases": 0, "experiments": 0.629, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.761 }, "string_id": "9606.ENSP00000354476" }, { "preferred_name": "HMGCR", "protein_id": "ENSP00000287936", "scores": { "coexpression": 0.128, "combined": 0.911, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.903 }, "string_id": "9606.ENSP00000287936" }, { "preferred_name": "SPTLC1", "protein_id": "ENSP00000262554", "scores": { "coexpression": 0.11, "combined": 0.908, "cooccurrence": 0, "databases": 0, "experiments": 0.867, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.291 }, "string_id": "9606.ENSP00000262554" }, { "preferred_name": "PI4KA", "protein_id": "ENSP00000255882", "scores": { "coexpression": 0, "combined": 0.906, "cooccurrence": 0, "databases": 0, "experiments": 0.86, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.361 }, "string_id": "9606.ENSP00000255882" }, { "preferred_name": "LDLRAP1", "protein_id": "ENSP00000363458", "scores": { "coexpression": 0, "combined": 0.823, "cooccurrence": 0, "databases": 0, "experiments": 0, "gene_fusion": 0, "neighborhood": 0, "text_mining": 0.823 }, "string_id": "9606.ENSP00000363458" } ], "protein": { "annotation": "Proprotein convertase subtilisin/kexin type 9; Crucial player in the regulation of plasma cholesterol homeostasis. Binds to low-density lipid receptor family members: low density lipoprotein receptor (LDLR), very low density lipoprotein receptor (VLDLR), apolipoprotein E receptor (LRP1/APOER) and apolipoprotein receptor 2 (LRP8/APOER2), and promotes their degradation in intracellular acidic compartments. Acts via a non- proteolytic mechanism to enhance the degradation of the hepatic LDLR through a clathrin LDLRAP1/ARH-mediated pathway. May prevent the recycling of LDLR from endosomes t [...] ", "inputs": [ "PCSK9" ], "preferred_name": "PCSK9", "protein_id": "ENSP00000303208", "string_id": "9606.ENSP00000303208" }, "query": "PCSK9", "source_url": "https://version-12-5.string-db.org/cgi/network?identifiers=9606.ENSP00000303208&species=9606&required_score=700&network_type=functional", "species": { "name": "Homo sapiens", "taxon_id": 9606 }, "string_version": "12.5" } ``` ### Enrichment - Capability: `annotations/enrichment` - Description: Functional enrichment of a list of 2 to 200 proteins in one species against the whole genome, as STRING computes it: the terms the list is over-represented for, with the term's category, source database and licence, ID, name, how many of your proteins and how many genome proteins have it, p-value, FDR and which of your genes carry it. Categories are Gene Ontology (Process, Function, Component), UniProt Keywords, Reactome (RCTM), WikiPathways, MSigDB Hallmark, COMPARTMENTS, TISSUES, DISEASES, InterPro, Pfam, PubMed papers (PMID), STRING network clusters (NetworkNeighborAL) and Mammalian Phenotype (MPO). Categories whose source licence does not permit commercial redistribution (KEGG, SMART, the Human Phenotype Ontology) or is unverified are left out, and excluded_categories counts what was dropped and why; no term data from them is returned. Inputs are mapped first (gene symbol, UniProt accession, Ensembl protein ID or STRING ID; unmapped ones warn); genes lists preferred names, the gene symbols to join to genenames-org or gene-ncbi-nlm-nih-gov, and the STRING ID embeds the Ensembl protein ID (protein_id; join to uniprot-org proteins/map_ids). Also the STRING version, the licence of STRING (CC BY 4.0) and of every source database present. - Instructions: What a gene or protein list has in common: GO processes, pathways, diseases, tissues, domains, literature. 'Enrichment for this 10-gene list'. Choose it for a broad multi-source answer and for non-human species; for Reactome pathway analysis alone (with Reactome's own statistics and pathway hierarchy) use reactome-org. Pass categories (Process, RCTM, WikiPathways) when you want ontology or pathway terms: PMID and NetworkNeighborAL terms often rank first by FDR. Needs at least 2 different proteins; STRING would otherwise add the protein's ten best partners, which this function does not do. For how the proteins connect to each other use network. - Cost: 5 credits per call - Capability file: [Enrichment](https://firecrawl.dev/alexandria/agents/providers/string-db-org/annotations/enrichment) Accepted options: - `categories` (string[]): Only these categories (case does not matter). Omit for all of them; KEGG, SMART, HPO and other categories are never returned. Example: `[]` - `fdr` (number): Keep terms with FDR at or below this, 0 to 1. Example: `0.05` - `limit` (number): Most terms to return, lowest FDR first. significant_terms says how many passed. Example: `50` - `proteins` (string[], required): Between 2 and 200 different proteins, each a gene symbol (PCSK9, Trp53), UniProt accession (P04637), Ensembl protein ID (ENSP00000269305) or STRING ID (9606.ENSP00000269305). Pass one array item per protein. Example: `[]` - `species` (number): The organism: an NCBI taxon ID (9606 human, 10090 mouse, 10116 rat, 7955 zebrafish, 7227 fruit fly, 6239 C. elegans, 4932 baker's yeast, 3702 Arabidopsis, 511145 E. coli K-12; STRING covers about 12,500) or one of the names human, mouse, rat, zebrafish, fruit fly, worm, yeast, arabidopsis, e. coli, chicken, cow, pig, dog (or the Latin name). Defaults to human, or to the taxon of a STRING ID given as protein (10090.ENSMUSP00000104298 is mouse). Proteins are looked up in this species only. Example: `9606` Response schema example: ```json { "categories": null, "excluded_categories": [ { "category": "GWAS", "reason": "not on the allowlist: the licence of this category's source has not been verified to permit commercial redistribution", "terms_omitted": 426 }, { "category": "HPO", "reason": "Human Phenotype Ontology: its licence requires showing the HPO file version and no alteration, and STRING does not expose the version", "terms_omitted": 31 }, { "category": "KEGG", "reason": "KEGG: non-academic use requires a commercial licence (https://www.kegg.jp/kegg/legal.html)", "terms_omitted": 3 } ], "fdr_threshold": 0.05, "license": { "attribution": "STRING v12.5 (https://string-db.org), STRING Consortium; Szklarczyk D, et al. The STRING database in 2025: protein networks with directionality of regulation. Nucleic Acids Res. 2025;53(D1):D730-D737.", "changes": "Reformatted by Firecrawl: field names changed, the seven evidence channels named, results sorted and cut to the requested limit. STRING's scores and statistics are unchanged. Enrichment categories whose source licence does not permit commercial redistribution, or has not been verified, were omitted (see excluded_categories); terms are otherwise as STRING returns them, cut to the requested FDR, categories and limit.", "enrichment_sources": [ { "category": "NetworkNeighborAL", "database": "STRING local network clusters", "license": "CC BY 4.0", "license_url": "https://creativecommons.org/licenses/by/4.0/" }, { "category": "PMID", "database": "PubMed (NLM)", "license": "NLM terms: courtesy of the U.S. National Library of Medicine; may not be the most current PubMed data", "license_url": "https://www.nlm.nih.gov/databases/download/terms_and_conditions.html" }, { "category": "WikiPathways", "database": "WikiPathways", "license": "CC0 1.0", "license_url": "https://creativecommons.org/publicdomain/zero/1.0/" } ], "name": "CC BY 4.0", "url": "https://creativecommons.org/licenses/by/4.0/" }, "licensed_terms": 334, "observed_at_ms": 1793394903895, "proteins": [ { "annotation": "Low-density lipoprotein receptor; Binds LDL, the major cholesterol-carrying lipoprotein of plasma, and transports it into cells by endocytosis. In order to be internalized, the receptor-ligand complexes must first cluster into clathrin-coated pits. (Microbial infection) Acts as a receptor for Vesicular stomatitis virus; Belongs to the LDLR family.", "inputs": [ "LDLR" ], "preferred_name": "LDLR", "protein_id": "ENSP00000454071", "string_id": "9606.ENSP00000454071" }, { "annotation": "Proprotein convertase subtilisin/kexin type 9; Crucial player in the regulation of plasma cholesterol homeostasis. Binds to low-density lipid receptor family members: low density lipoprotein receptor (LDLR), very low density lipoprotein receptor (VLDLR), apolipoprotein E receptor (LRP1/APOER) and apolipoprotein receptor 2 (LRP8/APOER2), and promotes their degradation in intracellular acidic compartments. Acts via a non- proteolytic mechanism to enhance the degradation of the hepatic LDLR through a clathrin LDLRAP1/ARH-mediated pathway. May prevent the recycling of LDLR from endosomes t [...] ", "inputs": [ "PCSK9" ], "preferred_name": "PCSK9", "protein_id": "ENSP00000303208", "string_id": "9606.ENSP00000303208" }, { "annotation": "Apolipoprotein B-100; Apolipoprotein B is a major protein constituent of chylomicrons (apo B-48), LDL (apo B-100) and VLDL (apo B-100). Apo B- 100 functions as a recognition signal for the cellular binding and internalization of LDL particles by the apoB/E receptor.", "inputs": [ "APOB" ], "preferred_name": "APOB", "protein_id": "ENSP00000233242", "string_id": "9606.ENSP00000233242" }, { "annotation": "Apolipoprotein E; APOE is an apolipoprotein, a protein associating with lipid particles, that mainly functions in lipoprotein-mediated lipid transport between organs via the plasma and interstitial fluids. APOE is a core component of plasma lipoproteins and is involved in their production, conversion and clearance. Apoliproteins are amphipathic molecules that interact both with lipids of the lipoprotein particle core and the aqueous environment of the plasma. As such, APOE associates with chylomicrons, chylomicron remnants, very low density lipoproteins (VLDL) and intermediate density [...] ", "inputs": [ "APOE" ], "preferred_name": "APOE", "protein_id": "ENSP00000252486", "string_id": "9606.ENSP00000252486" }, { "annotation": "Lipoprotein lipase; Key enzyme in triglyceride metabolism. Catalyzes the hydrolysis of triglycerides from circulating chylomicrons and very low density lipoproteins (VLDL), and thereby plays an important role in lipid clearance from the blood stream, lipid utilization and storage. Mediates margination of triglyceride-rich lipoprotein particles in capillaries. Recruited to its site of action on the luminal surface of vascular endothelium by binding to GPIHBP1 and cell surface heparan sulfate proteoglycans.", "inputs": [ "LPL" ], "preferred_name": "LPL", "protein_id": "ENSP00000497642", "string_id": "9606.ENSP00000497642" }, { "annotation": "Phospholipid-transporting ATPase ABCA1; Catalyzes the translocation of specific phospholipids from the cytoplasmic to the extracellular/lumenal leaflet of membrane coupled to the hydrolysis of ATP. Thereby, participates to phospholipids transfer to apoliproteins to form nascent high density lipoproteins/HDLs. Transports preferentially phosphatidylcholine over phosphatidylserine. May play a similar role in the efflux of intracellular cholesterol to apoliproteins and the formation of nascent high density lipoproteins/HDLs ; Belongs to the ABC transporter superfamily. ABCA family.", "inputs": [ "ABCA1" ], "preferred_name": "ABCA1", "protein_id": "ENSP00000363868", "string_id": "9606.ENSP00000363868" }, { "annotation": "Phosphatidylcholine-sterol acyltransferase; Central enzyme in the extracellular metabolism of plasma lipoproteins. Synthesized mainly in the liver and secreted into plasma where it converts cholesterol and phosphatidylcholines (lecithins) to cholesteryl esters and lysophosphatidylcholines on the surface of high and low density lipoproteins (HDLs and LDLs). The cholesterol ester is then transported back to the liver. Has a preference for plasma 16:0-18:2 or 18:O-18:2 phosphatidylcholines. Also produced in the brain by primary astrocytes, and esterifies free cholesterol on nascent APOE-c [...] ", "inputs": [ "LCAT" ], "preferred_name": "LCAT", "protein_id": "ENSP00000264005", "string_id": "9606.ENSP00000264005" }, { "annotation": "Cholesteryl ester transfer protein; Involved in the transfer of neutral lipids, including cholesteryl ester and triglyceride, among lipoprotein particles. Allows the net movement of cholesteryl ester from high density lipoproteins/HDL to triglyceride-rich very low density lipoproteins/VLDL, and the equimolar transport of triglyceride from VLDL to HDL. Regulates the reverse cholesterol transport, by which excess cholesterol is removed from peripheral tissues and returned to the liver for elimination ; Belongs to the BPI/LBP/Plunc superfamily. BPI/LBP family.", "inputs": [ "CETP" ], "preferred_name": "CETP", "protein_id": "ENSP00000200676", "string_id": "9606.ENSP00000200676" }, { "annotation": "NPC1-like intracellular cholesterol transporter 1; Plays a major role in cholesterol homeostasis. Is critical for the uptake of cholesterol across the plasma membrane of the intestinal enterocyte. Is the direct molecular target of ezetimibe, a drug that inhibits cholesterol absorption. Lack of activity leads to multiple lipid transport defects. The protein may have a function in the transport of multiple lipids and their homeostasis, and may play a critical role in regulating lipid metabolism. Acts as a negative regulator of NPC2 and down-regulates its expression and secretion by inhib [...] ", "inputs": [ "NPC1L1" ], "preferred_name": "NPC1L1", "protein_id": "ENSP00000289547", "string_id": "9606.ENSP00000289547" }, { "annotation": "3-hydroxy-3-methylglutaryl-coenzyme A reductase; Transmembrane glycoprotein that is the rate-limiting enzyme in cholesterol biosynthesis as well as in the biosynthesis of nonsterol isoprenoids that are essential for normal cell function including ubiquinone and geranylgeranyl proteins.", "inputs": [ "HMGCR" ], "preferred_name": "HMGCR", "protein_id": "ENSP00000287936", "string_id": "9606.ENSP00000287936" } ], "significant_terms": 334, "source_url": "https://version-12-5.string-db.org/cgi/network?identifiers=9606.ENSP00000454071%0D9606.ENSP00000303208%0D9606.ENSP00000233242%0D9606.ENSP00000252486%0D9606.ENSP00000497642%0D9606.ENSP00000363868%0D9606.ENSP00000264005%0D9606.ENSP00000200676%0D9606.ENSP00000289547%0D9606.ENSP00000287936&species=9606&required_score=400&network_type=functional", "species": { "name": "Homo sapiens", "taxon_id": 9606 }, "string_version": "12.5", "term_count": 15, "terms": [ { "category": "WikiPathways", "description": "Cholesterol metabolism", "fdr": 2.13e-22, "genes": [ "CETP", "APOB", "APOE", "LCAT", "HMGCR", "NPC1L1", "PCSK9", "ABCA1", "LDLR", "LPL" ], "genes_in_background": 72, "genes_in_set": 10, "p_value": 2.22e-25, "source_database": "WikiPathways", "source_license": "CC0 1.0", "term": "WP5304" }, { "category": "PMID", "description": "(2009) Lipoproteins, cholesterol homeostasis and cardiac health.", "fdr": 4.55e-22, "genes": [ "CETP", "APOB", "APOE", "LCAT", "HMGCR", "NPC1L1", "PCSK9", "ABCA1", "LDLR", "LPL" ], "genes_in_background": 35, "genes_in_set": 10, "p_value": 7.59e-29, "source_database": "PubMed (NLM)", "source_license": "NLM terms: courtesy of the U.S. National Library of Medicine; may not be the most current PubMed data", "term": "PMID:19584955" }, { "category": "PMID", "description": "(2025) Pediatric Familial Hypercholesterolemia: Targeting Intestinal Absorption and Other Therapeutic Strategies.", "fdr": 7.9e-22, "genes": [ "CETP", "APOB", "APOE", "LCAT", "HMGCR", "NPC1L1", "PCSK9", "ABCA1", "LDLR", "LPL" ], "genes_in_background": 40, "genes_in_set": 10, "p_value": 3.5e-28, "source_database": "PubMed (NLM)", "source_license": "NLM terms: courtesy of the U.S. National Library of Medicine; may not be the most current PubMed data", "term": "PMID:40732982" }, { "category": "PMID", "description": "(2016) Surprises From Genetic Analyses of Lipid Risk Factors for Atherosclerosis.", "fdr": 7.9e-22, "genes": [ "CETP", "APOB", "APOE", "HMGCR", "NPC1L1", "PCSK9", "ABCA1", "LDLR", "LPL" ], "genes_in_background": 18, "genes_in_set": 9, "p_value": 3.96e-28, "source_database": "PubMed (NLM)", "source_license": "NLM terms: courtesy of the U.S. National Library of Medicine; may not be the most current PubMed data", "term": "PMID:26892959" }, { "category": "PMID", "description": "(2023) Searching for new genes associated with the familial hypercholesterolemia phenotype using whole-genome sequencing and machine learning.", "fdr": 9.01e-22, "genes": [ "CETP", "APOB", "APOE", "LCAT", "HMGCR", "NPC1L1", "PCSK9", "ABCA1", "LDLR", "LPL" ], "genes_in_background": 42, "genes_in_set": 10, "p_value": 6.08e-28, "source_database": "PubMed (NLM)", "source_license": "NLM terms: courtesy of the U.S. National Library of Medicine; may not be the most current PubMed data", "term": "PMID:37808210" }, { "category": "PMID", "description": "(2021) The impact of lipid-lowering medications on coronary artery plaque characteristics.", "fdr": 9.01e-22, "genes": [ "CETP", "APOB", "APOE", "HMGCR", "NPC1L1", "PCSK9", "ABCA1", "LDLR", "LPL" ], "genes_in_background": 19, "genes_in_set": 9, "p_value": 7.52e-28, "source_database": "PubMed (NLM)", "source_license": "NLM terms: courtesy of the U.S. National Library of Medicine; may not be the most current PubMed data", "term": "PMID:34877559" }, { "category": "WikiPathways", "description": "Metabolic pathway of LDL HDL and TG including diseases", "fdr": 9.34e-22, "genes": [ "CETP", "APOB", "APOE", "LCAT", "PCSK9", "ABCA1", "LDLR", "LPL" ], "genes_in_background": 17, "genes_in_set": 8, "p_value": 1.95e-24, "source_database": "WikiPathways", "source_license": "CC0 1.0", "term": "WP4522" }, { "category": "PMID", "description": "(2014) Cholesterol and lipoprotein metabolism: Early Career Committee contribution.", "fdr": 1.37e-21, "genes": [ "CETP", "APOB", "APOE", "LCAT", "HMGCR", "NPC1L1", "PCSK9", "ABCA1", "LDLR" ], "genes_in_background": 20, "genes_in_set": 9, "p_value": 1.37e-27, "source_database": "PubMed (NLM)", "source_license": "NLM terms: courtesy of the U.S. National Library of Medicine; may not be the most current PubMed data", "term": "PMID:25142876" }, { "category": "PMID", "description": "(2018) Unexplained reciprocal regulation of diabetes and lipoproteins.", "fdr": 1.79e-21, "genes": [ "CETP", "APOB", "APOE", "HMGCR", "NPC1L1", "PCSK9", "ABCA1", "LDLR", "LPL" ], "genes_in_background": 21, "genes_in_set": 9, "p_value": 2.39e-27, "source_database": "PubMed (NLM)", "source_license": "NLM terms: courtesy of the U.S. National Library of Medicine; may not be the most current PubMed data", "term": "PMID:29708925" }, { "category": "PMID", "description": "(2020) The relationship between circulating lipids and breast cancer risk: A Mendelian randomization study.", "fdr": 1.79e-21, "genes": [ "CETP", "APOB", "APOE", "LCAT", "HMGCR", "NPC1L1", "PCSK9", "ABCA1", "LDLR" ], "genes_in_background": 21, "genes_in_set": 9, "p_value": 2.39e-27, "source_database": "PubMed (NLM)", "source_license": "NLM terms: courtesy of the U.S. National Library of Medicine; may not be the most current PubMed data", "term": "PMID:32915777" }, { "category": "NetworkNeighborAL", "description": "Protein-lipid complex, and Plasma lipoprotein assembly, remodeling, and clearance", "fdr": 1.82e-21, "genes": [ "CETP", "APOB", "APOE", "LCAT", "HMGCR", "NPC1L1", "PCSK9", "ABCA1", "LDLR", "LPL" ], "genes_in_background": 76, "genes_in_set": 10, "p_value": 3.95e-25, "source_database": "STRING local network clusters", "source_license": "CC BY 4.0", "term": "CL:16260" }, { "category": "PMID", "description": "(2009) Discovery and validation of new molecular targets in treating dyslipidemia: the role of human genetics.", "fdr": 2.69e-21, "genes": [ "CETP", "APOB", "LCAT", "HMGCR", "NPC1L1", "PCSK9", "ABCA1", "LDLR", "LPL" ], "genes_in_background": 22, "genes_in_set": 9, "p_value": 4.05e-27, "source_database": "PubMed (NLM)", "source_license": "NLM terms: courtesy of the U.S. National Library of Medicine; may not be the most current PubMed data", "term": "PMID:20211435" }, { "category": "PMID", "description": "(2021) Multitrait GWAS to connect disease variants and biological mechanisms.", "fdr": 6.37e-21, "genes": [ "CETP", "APOB", "APOE", "LCAT", "HMGCR", "NPC1L1", "PCSK9", "ABCA1", "LDLR" ], "genes_in_background": 24, "genes_in_set": 9, "p_value": 1.06e-26, "source_database": "PubMed (NLM)", "source_license": "NLM terms: courtesy of the U.S. National Library of Medicine; may not be the most current PubMed data", "term": "PMID:34460823" }, { "category": "PMID", "description": "(2023) HDL-Based Therapy: Vascular Protection at All Stages.", "fdr": 9.05e-21, "genes": [ "CETP", "APOB", "APOE", "LCAT", "HMGCR", "NPC1L1", "PCSK9", "ABCA1", "LDLR" ], "genes_in_background": 25, "genes_in_set": 9, "p_value": 1.66e-26, "source_database": "PubMed (NLM)", "source_license": "NLM terms: courtesy of the U.S. National Library of Medicine; may not be the most current PubMed data", "term": "PMID:36979690" }, { "category": "PMID", "description": "(2026) The Past, Present, and Future of Dyslipidemia: A Narrative Review.", "fdr": 1.2e-20, "genes": [ "CETP", "APOB", "LCAT", "HMGCR", "NPC1L1", "PCSK9", "ABCA1", "LDLR", "LPL" ], "genes_in_background": 26, "genes_in_set": 9, "p_value": 2.54e-26, "source_database": "PubMed (NLM)", "source_license": "NLM terms: courtesy of the U.S. National Library of Medicine; may not be the most current PubMed data", "term": "PMID:42078291" } ], "total_terms": 794, "unmapped": [] } ```