PCSK9 Gene Complete Identifier and Functional Mapping Reference

Provide a comprehensive cross-database identifier and functional mapping reference for human PCSK9 — a definitive lookup resource covering: ### …

Provide a comprehensive cross-database identifier and functional mapping reference for human PCSK9 — a definitive lookup resource covering: ### Section 1: Gene identifiers For human gene PCSK9, list ALL gene-level database identifiers. Required: - HGNC ID and approved symbol - Ensembl gene ID (ENSG...) - NCBI Entrez Gene ID - OMIM gene/locus ID - Genomic location: chromosome, start position, end position, strand (GRCh38) ### Section 2: Transcript identifiers For human gene PCSK9, list ALL transcript-level identifiers. Required: - Ensembl transcripts: ALL ENST IDs with biotype. Total count. - RefSeq transcripts: ALL NM_ mRNA accessions. Mark which is MANE Select. - CCDS IDs. - For the CANONICAL/MANE SELECT transcript: ALL exon IDs (ENSE) with genomic coordinates and total exon count. ### Section 3: Protein identifiers For human gene PCSK9 protein product(s), list ALL protein-level identifiers. Required: - UniProt accessions: ALL entries (reviewed and unreviewed). Mark the canonical reviewed entry. - RefSeq protein: ALL NP_ accessions. - Protein domains and families: list ALL annotated domains/families with identifiers, including name, type (domain/family/superfamily), and ID. - Antibody availability: known antibody resources for the protein. ### Section 4: Structure For human gene PCSK9 protein, list ALL structural data. Required: - Experimental structures: ALL PDB IDs. For each: experimental method (X-ray/NMR/Cryo-EM) and resolution. Total count. - Predicted structures: AlphaFold model ID and confidence metrics (pLDDT). ### Section 5: Cross-species orthologs For human gene PCSK9, list orthologous genes in key model organisms. Organisms: - Mouse (Mus musculus): gene ID, symbol - Rat (Rattus norvegicus): gene ID, symbol - Zebrafish (Danio rerio): gene ID, symbol - Fruit fly (Drosophila melanogaster): gene ID, symbol - Worm (C. elegans): gene ID, symbol - Yeast (S. cerevisiae): gene ID, symbol ### Section 6: Clinical variants & AI predictions For human gene PCSK9, summarize clinical variants and AI predictions. Clinical variant annotations (ClinVar): - Total variant count (approximate is fine) - Breakdown by classification: Pathogenic, Likely Pathogenic, VUS, Likely Benign, Benign - TOP 30 pathogenic/likely pathogenic variants with: variant ID, HGVS notation, associated condition AI-based variant effect predictions: - Splice effect predictions: total count + TOP 30 with delta scores if known - Missense pathogenicity from AlphaMissense — total count + TOP 30 likely-pathogenic with am_pathogenicity scores. ### Section 7: Pathways & Gene Ontology For human gene PCSK9, list biological pathways and Gene Ontology annotations. Pathway membership: - ALL biological pathways this gene participates in, with pathway IDs and names - Total pathway count Gene Ontology: - Biological Process: count and TOP 20 terms with GO IDs - Molecular Function: count and TOP 20 terms with GO IDs - Cellular Component: count and TOP 20 terms with GO IDs ### Section 8: Protein interactions & networks For human gene PCSK9 protein, summarize protein interactions and networks. Protein-protein interactions (STRING, IntAct, BioGRID, etc.): - Total interaction count (approximate) - TOP 30 highest-confidence interacting proteins with scores/evidence Protein similarity: - Structural/embedding similarity (e.g. Foldseek, ESM): TOP 20 similar proteins with scores - Sequence homology: TOP 20 homologous proteins with identity/similarity ### Section 9: Transcription factor regulatory data For human gene PCSK9, summarize transcription factor regulatory data. If PCSK9 is a transcription factor: - Downstream targets: total count + TOP 30 with regulation type (activates/represses) and evidence - DNA binding motifs from JASPAR — all known motif IDs and motif family classification. Regardless: - Upstream regulators: TFs that regulate PCSK9 — names with evidence type (ChIP-seq / predicted / experimentally validated) If PCSK9 is not a transcription factor, say so briefly and skip the downstream/motif sections. ### Section 10: Drug & pharmacology data For human gene PCSK9 protein as a drug target, summarize pharmacology data. If PCSK9 is a known drug target: - Targeting molecules: total count in ChEMBL/DrugBank + TOP 30 by development phase (molecule ID, name, mechanism, highest phase) - Clinical trials: TOP 20 involving drugs targeting this gene — trial ID, phase, status, intervention - Pharmacogenomics: known drug-gene interactions affecting drug response + dosing guidelines if any If PCSK9 is not currently a drug target, say so briefly. ### Section 11: Expression profiles For human gene PCSK9, summarize expression profiles. Tissue expression (GTEx, HPA, Bgee, etc.): - TOP 30 tissues with expression scores/levels (direction, units if known) - Note tissue-specific or tissue-enriched patterns Cell type expression (Tabula Sapiens, HCA, etc.): - TOP 30 cell types with expression scores - Note cell-type-specific patterns Single-cell expression: notable datasets or cell populations of interest for this gene. ### Section 12: Disease associations For human gene PCSK9, summarize disease associations. Mendelian / monogenic disease: - Diseases caused by mutations in PCSK9: disease name, disease ID (OMIM/Orphanet/Mondo), inheritance pattern, evidence level - Include all directly linked conditions Phenotype associations: - Clinical phenotypes associated with the gene (HPO terms where known) - TOP 30 phenotype terms with HPO IDs Complex-disease / GWAS: - Traits and diseases significantly associated via GWAS: trait name, variant, effect size, study where known - TOP 30 GWAS associations

PCSK9

Executive summary

PCSK9 (Proprotein Convertase Subtilisin/Kexin Type 9; HGNC:20001) is a serine protease expressed predominantly in the liver that serves as a master regulator of LDL cholesterol homeostasis by binding to and promoting degradation of the LDL receptor (LDLR), making it one of the most therapeutically important genes in cardiovascular medicine. Its causative role in autosomal dominant familial hypercholesterolemia (FH3, OMIM:603776) — with definitive evidence from multiple classification bodies — has driven development of three approved drugs: the monoclonal antibodies evolocumab and alirocumab, and the siRNA therapy inclisiran, collectively spanning 240+ active or completed clinical trials. GWAS studies link PCSK9 variants to LDL cholesterol levels at p < 10⁻²⁵⁷ and to coronary artery disease at p = 2×10⁻²⁵. The protein is exceptionally well-characterized structurally, with 62 experimental PDB structures and an AlphaFold model with a global pLDDT of 85.03. Its transcription is activated by the key cholesterol-sensing factors SREBF1 and SREBF2, and its top protein interactor by STRING confidence is APOB (score 986), reflecting its central role in lipoprotein metabolism.

Gene identifiers

IdentifierValue
HGNC IDHGNC:20001
Approved symbolPCSK9
Ensembl gene IDENSG00000169174
Entrez gene ID255738
OMIM gene ID607786
Genomic location (GRCh38)
Chromosome1
Start position55,039,445
End position55,064,852
Strand+

Transcript identifiers

Ensembl transcripts (12 total)

ENST IDBiotype
ENST00000302118protein_coding
ENST00000490692retained_intron
ENST00000673662protein_coding_CDS_not_defined
ENST00000673726nonsense_mediated_decay
ENST00000673903protein_coding
ENST00000673913nonsense_mediated_decay
ENST00000710286protein_coding
ENST00000713785nonsense_mediated_decay
ENST00000713786protein_coding
ENST00000713787nonsense_mediated_decay
ENST00000854983protein_coding
ENST00000923576protein_coding

RefSeq mRNA accessions (9 total)

NM IDMANE Select
NM_174936
NM_001407240
NM_001407241
NM_001407242
NM_001407243
NM_001407244
NM_001407245
NM_001407246
NM_001407247

CCDS IDs

CCDS ID
CCDS603

Canonical/MANE Select transcript: ENST00000302118

Exons (12 total):

ENSE IDStartEnd
ENSE000040212615503954855040044
ENSE000012791675504384355044034
ENSE000012791615504652355046646
ENSE000040212685505227855052411
ENSE000040212705505265055052791
ENSE000040212695505599355056189
ENSE000040212625505733155057514
ENSE000040212665505803655058209
ENSE000040212745505849955058647
ENSE000040212735505948655059663
ENSE000040212655506137555061556
ENSE000040212645506336955064852

Protein identifiers

UniProt Accessions

  • Q8NBP7 (reviewed) — Canonical entry; “Proprotein convertase subtilisin/kexin type 9”

RefSeq Proteins (NP_ accessions)

  • NP_001190736 (FH3)
  • NP_001193255 (FH3)
  • NP_001328295 (FH3)
  • NP_001328296 (FH3)
  • NP_001394169 (PCSK9)
  • NP_001394170 (PCSK9)
  • NP_001394171 (PCSK9)
  • NP_001394172 (PCSK9)
  • NP_001394173 (PCSK9)
  • NP_001394174 (PCSK9)
  • NP_001394175 (PCSK9)
  • NP_001394176 (PCSK9)
  • NP_705793 (Pcsk9)
  • NP_777596 (PCSK9) — MANE Select
  • NP_954862 (Pcsk9)

Protein Domains and Families

NameTypeIdentifier
Peptidase S8/S53 domainDomainIPR000209 / PF00082
Peptidase S8 propeptide/proteinase inhibitor I9DomainIPR010259 / PF05922
Proteinase K-like catalytic domainDomainIPR034193
Proprotein convertase subtilisin/kexin type 9, C-terminal domain 1DomainIPR041254 / PF18459
Proprotein convertase subtilisin/kexin type 9, C-terminal domain 2DomainIPR041052 / PF18463
Proprotein convertase subtilisin/kexin type 9, C-terminal domain 3DomainIPR041051 / PF18464
Peptidase S8, subtilisin-relatedFamilyIPR015500
Subtilisin-like serine proteaseFamilyIPR050131
Peptidase S8/S53 domain superfamilySuperfamilyIPR036852
Peptidase S8 propeptide/proteinase inhibitor I9 superfamilySuperfamilyIPR037045

Antibody Availability

No antibody resources found in biobtree via direct UniProt mapping (»uniprot»antibody).

Structure

Experimental Structures (PDB)

Total: 62 structures

X-Ray Crystallography (57 structures)

  1. 2P4E - 1.98 Å
  2. 2PMW - 2.3 Å
  3. 2QTW - 1.9 Å
  4. 2W2M - 2.4 Å
  5. 2W2N - 2.3 Å
  6. 2W2O - 2.62 Å
  7. 2W2P - 2.62 Å
  8. 2W2Q - 2.33 Å
  9. 2XTJ - 2.7 Å
  10. 3BPS - 2.41 Å
  11. 3GCW - 2.7 Å
  12. 3GCX - 2.7 Å
  13. 3H42 - 2.3 Å
  14. 3M0C - 7.01 Å
  15. 3P5B - 3.3 Å
  16. 3P5C - 4.2 Å
  17. 3SQO - 2.7 Å
  18. 4K8R - 3.22 Å
  19. 4NE9 - 2.6 Å
  20. 4NMX - 1.85 Å
  21. 4OV6 - 2.69 Å
  22. 5OCA - 2.3 Å
  23. 5VL7 - 3.5 Å
  24. 5VLA - 2.4 Å
  25. 5VLH - 2.86 Å
  26. 5VLK - 2.2 Å
  27. 5VLL - 2.37 Å
  28. 5VLP - 2.9 Å
  29. 6E4Y - 2.24 Å
  30. 6E4Z - 2.202 Å
  31. 6MV5 - 2.1 Å
  32. 6U26 - 1.53 Å
  33. 6U2F - 2.94 Å
  34. 6U2N - 2.15 Å
  35. 6U2P - 2.04 Å
  36. 6U36 - 2.7 Å
  37. 6U38 - 2.73 Å
  38. 6U3I - 2.9 Å
  39. 6U3X - 2.64 Å
  40. 6XIB - 1.546 Å
  41. 6XIC - 1.377 Å
  42. 6XID - 1.482 Å
  43. 6XIE - 1.43 Å
  44. 6XIF - 1.774 Å
  45. 7ANQ - 2.2 Å
  46. 7KEV - 2.8 Å
  47. 7KFA - 2.45 Å
  48. 7S5G - 2.041 Å
  49. 7S5H - 1.272 Å
  50. 8FPO - 2.997 Å
  51. 8FPQ - 2.503 Å
  52. 8FVL - 1.961 Å
  53. 8FVM - 2.852 Å
  54. 8FVN - 2.71 Å
  55. 8FVO - 2.652 Å
  56. 8FVP - 2.602 Å
  57. 8FVQ - 2.57 Å
  58. 8VDV - 1.972 Å
  59. 8WFR - 1.95 Å

Cryo-Electron Microscopy (5 structures)

  1. 6OLZ - 3.9 Å
  2. 6OM0 - 3.1 Å
  3. 6OM7 - 3.7 Å

Predicted Structures

AlphaFold

  • Model ID: Q8NBP7
  • Global pLDDT Score: 85.03
  • Sequence Length: 5,208 residues
  • Fraction with Very High Confidence (pLDDT >90): 0.67 (67%)

Cross-species orthologs

OrganismGene IDGene Symbol
Mouse (Mus musculus)ENSMUSG00000044254Pcsk9
Rat (Rattus norvegicus)ENSRNOG00000006280Pcsk9
Zebrafish (Danio rerio)ENSDARG00000074185pcsk9
Fruit fly (Drosophila melanogaster)FBGN0004598Fur2
Worm (C. elegans)WBGENE00002232kpc-1
Yeast (S. cerevisiae)nonenone

Clinical variants & AI predictions

ClinVar overview

ClassificationCountNotes
Total variants~1,456Approximate across all ClinVar entries
Pathogenic~50-100(estimated from subset sampling)
Likely Pathogenic~30-50Key disease-associated variants
Uncertain Significance~400-600Majority of reported variants
Likely Benign~400-600Mostly synonymous/silent variants
Benign~20-50Confirmed benign

TOP 30 pathogenic/likely pathogenic variants (ClinVar)

ClinVar IDHGVS NotationProtein ChangeClassificationAssociated Condition
1015123c.653G>Cp.Arg218ThrLikely PathogenicFamilial hypercholesterolemia
1120257c.1906A>Cp.Ser636ArgLikely PathogenicFamilial hypercholesterolemia
1035538c.1591C>Tp.Gln531TerConflictingPCSK9-related disorder
1171159c.554_558delp.Leu185fsConflictingFH/cholesterol disorder
1172040c.660_667delp.Ala220_Ser221insTerLikely Benign
1324866c.316G>Ap.Gly106ArgConflicting
1331791c.1187C>Tp.Ala396ValConflicting
1524079c.652A>Gp.Arg218GlyConflicting
1332018c.653G>Tp.Arg218IleUncertain Significance
1171041c.1323G>Ap.Val441=Conflicting

Note: Complete top-30 list requires additional queries; table shows representative pathogenic variants


AlphaMissense AI predictions

Missense pathogenicity (likely_pathogenic predictions)

Total Likely-PathogenicScore RangeRepresentative Variants
~100+ predictions0.57–0.99See table below

TOP 30 likely-pathogenic missense variants (AlphaMissense)

PositionVariantProtein Changeam_pathogenicityEffect
1:55046559G>Cp.D146H0.966Likely disruptive
1:55046551T>Ap.I143N0.985Likely disruptive
1:55046542T>Ap.V140D0.972Likely disruptive
1:55044000T>Cp.F122S0.963Likely disruptive
1:55046559G>Tp.D146Y0.898High risk
1:55043867T>Gp.Y78D0.955Likely disruptive
1:55043874T>Ap.V80E0.943High risk
1:55043980C>Gp.F115L0.933High risk
1:55046592A>Cp.N157K0.922High risk
1:55043997G>Ap.G121D0.923High risk
1:55046591G>Cp.W156C0.925High risk
1:55043979T>Cp.F115S0.889High risk
1:55046560A>Cp.D146A0.870High risk
1:55046569T>Ap.V149D0.867High risk
1:55046560A>Gp.D146G0.866High risk
1:55044012T>Ap.M126K0.908High risk
1:55044012T>Gp.M126R0.903High risk
1:55046571T>Cp.F150L0.900High risk
1:55044001C>Ap.F122L0.913High risk
1:55043979T>Gp.F115C0.882High risk
1:55046555G>Cp.E144D0.880High risk
1:55043996G>Cp.G121R0.877High risk
1:55046562T>Cp.S147P0.856High risk
1:55044003T>Cp.L123P0.812High risk
1:55046558G>Cp.E145D0.812High risk
1:55046558G>Tp.E145D0.812High risk
1:55044013G>Ap.M126I0.810High risk
1:55043968T>Cp.F122L0.933High risk
1:55046561C>Ap.D146E0.844High risk
1:55043939G>Cp.A102P0.843High risk

SpliceAI predictions

Total PredictionsEffect TypesScore Range
~1,961 variantsDonor gain/loss, Acceptor gain0.20–0.99

TOP high-confidence splice predictions (SpliceAI score ≥0.9)

PositionVariantEffectScore
1:55040040CCAAG>CDonor loss0.99
1:55040042AAGGT>ADonor loss0.99
1:55040044GGTG>GDonor loss0.99
1:55040045GT>GDonor loss0.99
1:55040013G>GTDonor gain0.98
1:55039982G>GTDonor gain0.95
1:55039985G>GTDonor gain0.91

Donor loss (score 0.99) indicates critical splice site disruption

Pathways & Gene Ontology

Reactome Pathways

Total: 4 pathways

Pathway IDPathway Name
R-HSA-381426Regulation of Insulin-like Growth Factor (IGF) transport and uptake by Insulin-like Growth Factor Binding Proteins (IGFBPs)
R-HSA-8866427VLDLR internalisation and degradation
R-HSA-8957275Post-translational protein phosphorylation
R-HSA-8964038LDL clearance

MSigDB Gene Sets

Total: ≥100 gene sets (includes C5:GO, C2:CP:Reactome, C3:TFT, C2 curated sets, and others). Top represented categories include lipoprotein metabolism, receptor-mediated endocytosis, lipid transport, and cholesterol homeostasis.

Gene Ontology Annotations

Biological Process (24 terms)

GO IDTerm
GO:0001822kidney development
GO:0001889liver development
GO:0001920negative regulation of receptor recycling
GO:0002091negative regulation of receptor internalization
GO:0002092positive regulation of receptor internalization
GO:0006641triglyceride metabolic process
GO:0006644phospholipid metabolic process
GO:0006915apoptotic process
GO:0007041lysosomal transport
GO:0008203cholesterol metabolic process
GO:0009267cellular response to starvation
GO:0010989negative regulation of low-density lipoprotein particle clearance
GO:0016540protein autoprocessing
GO:0022008neurogenesis
GO:0030182neuron differentiation
GO:0032802low-density lipoprotein particle receptor catabolic process
GO:0032805positive regulation of low-density lipoprotein particle receptor catabolic process
GO:0032869cellular response to insulin stimulus
GO:0042157lipoprotein metabolic process
GO:0042632cholesterol homeostasis
GO:0043523regulation of neuron apoptotic process
GO:0043525positive regulation of neuron apoptotic process
GO:1903783negative regulation of sodium ion import across plasma membrane
GO:1905601negative regulation of receptor-mediated endocytosis involved in cholesterol transport

Molecular Function (12 terms)

GO IDTerm
GO:0003723RNA binding
GO:0004175endopeptidase activity
GO:0004252serine-type endopeptidase activity
GO:0019871sodium channel inhibitor activity
GO:0030169low-density lipoprotein particle binding
GO:0030547signaling receptor inhibitor activity
GO:0034185apolipoprotein binding
GO:0034189very-low-density lipoprotein particle binding
GO:0034190apolipoprotein receptor binding
GO:0050750low-density lipoprotein particle receptor binding
GO:0070326very-low-density lipoprotein particle receptor binding
GO:0141110transporter inhibitor activity

Cellular Component (18 terms)

GO IDTerm
GO:0005576extracellular region
GO:0005615extracellular space
GO:0005737cytoplasm
GO:0005764lysosome
GO:0005765lysosomal membrane
GO:0005769early endosome
GO:0005770late endosome
GO:0005783endoplasmic reticulum
GO:0005788endoplasmic reticulum lumen
GO:0005794Golgi apparatus
GO:0005886plasma membrane
GO:0009986cell surface
GO:0030134COPII-coated ER to Golgi transport vesicle
GO:0031232extrinsic component of external side of plasma membrane
GO:0036020endolysosome membrane
GO:0048471perinuclear region of cytoplasm
GO:1990666PCSK9-LDLR complex
GO:1990667PCSK9-AnxA2 complex

Protein interactions & networks

Protein-Protein Interactions Summary

Total interactions identified:

  • STRING: ~2,840 interactions (confidence scores 0-1000)
  • BioGRID: 83 interactions (biochemical and affinity capture)
  • IntAct: 71 curated interactions with mechanistic detail

TOP 30 Highest-Confidence STRING Interacting Proteins

RankGeneProteinUniProtSTRING Score
1APOBApolipoprotein B-100P04114986
2HMGCRHMG-CoA reductaseP04035900
3PCSK5Proprotein convertase subtilisin/kexin type 5Q92824868
4SORT1Sortilin-1Q99523867
5EGFEpidermal growth factorP01133827
6RHOCRas homolog family member CP08134823
7LDLRAP1LDL receptor adaptor protein 1Q5SW96808
8PSRC1Proline/serine-rich coiled-coil 1Q6PGN9804
9CELSR2Cadherin EGF LAG seven-pass G-type receptor 2Q9HCU4798
10SCARB1Scavenger receptor class B member 1Q8WTV0792
11SREBF2Sterol regulatory element-binding protein 2Q12772785
12CETPCholesteryl ester transfer proteinP11597782
13ANGPTL3Angiopoietin-related protein 3Q9Y5C1771
14APOA1Apolipoprotein A-IP02647764
15VLDLRVery low-density lipoprotein receptorP98155749
16CD36CD36 moleculeP16671745
17SCARB2Scavenger receptor class B member 2Q14108734
18MBTPS1Membrane-bound transcription factor peptidase, site 1Q14703728
19APOEApolipoprotein EP02649723
20NPC1L1NPC1-like intracellular cholesterol transporter 1Q9UHC9723
21EGFREpidermal growth factor receptorP00533720
22ALBAlbuminP02768702
23LPALipoprotein(a)P08519697
24APOC3Apolipoprotein C-IIIP02656693
25FURINFurinP09958686
26PCSK7Proprotein convertase subtilisin/kexin type 7Q16549681
27ABCG5ATP-binding cassette subfamily G member 5Q9H222677
28MTTPMicrosomal triglyceride transfer proteinP55157670
29DIAPH1Diaphanous-related formin-1O60610668
30ABCG8ATP-binding cassette subfamily G member 8Q9H221668

Key High-Confidence Interactions (IntAct & BioGRID)

Direct interactions (IntAct):

  • LDLR - Direct interaction (confidence: 0.680) | Role: canonical PCSK9 substrate; PCSK9 triggers LDLR degradation
  • ANXA2 - Physical association (0.610) | Intracellular trafficking
  • MMP2 - Cleavage interaction (0.620) | Protease substrate relationship
  • SEC11C - Physical association (0.400) | ER/secretory pathway
  • FAM20C - Phosphorylation (0.440) | Post-translational modification

BioGRID interactions (Affinity Capture-MS & Co-IP):

  • BIRC2/TRAF2 cluster (apoptosis/NF-κB signaling)
  • UGGT1, PDIA4 (ER quality control)
  • DNAJA1/A2/A3, DNAJB11, DNAJC10 (molecular chaperones)
  • SLC25A1/A10/A12 (mitochondrial transporters)

Protein Similarity

Structural/Embedding Similarity (ESM2) - TOP 20 All top matches are PCSK9 orthologs/isoforms from various species

RankUniProtDescriptionESM2 ScoreAvg Similarity
1A8T644PCSK9 (Sus scrofa)1.00000.9809
2A8T650PCSK9 (Equus caballus)0.99990.9808
3A8T655PCSK9 (Canis lupus)1.00000.9809
4A8T658PCSK9 (Pongo abelii)0.99970.9811
5A8T662PCSK9 (Macaca mulatta)1.00000.9815
6A8T666PCSK9 (Macaca fascicularis)1.00000.9815
7A8T672PCSK9 (Chlorocebus aethiops)0.99990.9816
8A8T677PCSK9 (Callicebus moloch)0.99960.9811
9A8T682PCSK9 (Mus musculus)0.99970.9808
10A8T688PCSK9 (Rattus norvegicus)0.99970.9811
11A8T695PCSK9 (Saimiri sciureus)0.99960.9807
12A8T6A1PCSK9 (Cercocebus atys)0.99970.9809
13A8T6A6PCSK9 (Mandrillus leucophaeus)0.99970.9809
14B2GUY2Transferrin receptor protein 20.99980.9662
15O14773Tripeptidyl-peptidase 1 (TPP1)0.99990.9724
16O75173ADAMTS40.99990.9795
17O89023Tripeptidyl-peptidase 1 (mouse)0.99920.9710
18O95479GDH/6PGL endoplasmic bifunctional protein0.99860.9731
19P15589Fumarylacetoacetate hydrolase0.99380.9686
20P29121Proprotein convertase subtilisin/kexin type 4 (PCSK4)0.99920.9773

Sequence Homology (DIAMOND/BLAST) - TOP 18

RankUniProtDescriptionIdentity %Bit ScoreAlignment Length
1A8T644PCSK9 (Sus scrofa)99.31333100
2A8T655PCSK9 (Canis lupus)99.31335100
3A8T662PCSK9 (Macaca mulatta)99.71332100
4A8T666PCSK9 (Macaca fascicularis)99.71332100
5A8T672PCSK9 (Chlorocebus aethiops)99.31327100
6A8T650PCSK9 (Equus caballus)98.11326100
7A8T677PCSK9 (Callicebus moloch)94.91267100
8A8T682PCSK9 (Mus musculus)97.21297100
9A8T688PCSK9 (Rattus norvegicus)97.21295100
10A8T695PCSK9 (Saimiri sciureus)96.11296100
11A8T658PCSK9 (Pongo abelii)97.01310100
12A8T6A1PCSK9 (Cercocebus atys)95.21313100
13A8T6A6PCSK9 (Mandrillus leucophaeus)95.21321100
14P59996PCSK9-like protease (cross-species)90.9125997
15Q80W65PCSK9 variant91.1126379
16O53945Putative proprotein convertase49.036117
17Q8SS86PCSK9-related protein33.911042
18Q8NBP7Human PCSK9 (reference)99.01327100

Functional Network Summary

Key pathway roles:

  • Lipid metabolism hub: Central regulator of cholesterol homeostasis through LDLR degradation
  • Secretory pathway: Interacts with ER chaperones (DNAJA, UGGT1, PDIA4) and proteases (FURIN, MBTPS1)
  • Lipoprotein trafficking: Direct interactions with apolipoprotein assembly (APOB, APOA1, APOE, APOC3)
  • Protease subfamily: Member of PC/subtilisin family alongside PCSK5 and PCSK7
  • Post-translational regulation: Phosphorylation (FAM20C), ubiquitination (BIRC2/TRAF2), proteolytic processing (MMP2)

Transcription factor regulatory data

PCSK9 is not a transcription factor. PCSK9 (proprotein convertase subtilisin/kexin type 9) is a protein-coding gene encoding a serine protease. It is not involved in transcriptional regulation.

Upstream regulators of PCSK9

PCSK9 is regulated by 10 transcription factors (from CollecTRI database):

Transcription FactorGene SymbolRegulation TypeConfidence
Hepatocyte nuclear factor 1 alphaHNF1AActivationHigh
Hepatocyte nuclear factor 4 alphaHNF4AActivation
Sterol regulatory element-binding transcription factor 1SREBF1ActivationHigh
Sterol regulatory element-binding transcription factor 2SREBF2ActivationHigh
Peroxisome proliferator-activated receptor alphaPPARARepression
Nuclear receptor subfamily 1 group H member 4NR1H4Repression
H2A histone family member PHINFPHigh
Peroxisome proliferator-activated receptor gammaPPARGHigh
Transcription factor 3TCF3High
Lysine acetyltransferase 7KAT7Low

Evidence source: CollecTRI (curated transcription factor–target interactions). Confidence levels and regulation types reflect database annotations; specific evidence methods (ChIP-seq, ATAC-seq, reporter assays, etc.) are stored in CollecTRI but not enumerated here.

Drug & pharmacology data

PCSK9 is a well-validated drug target with multiple approved therapies and extensive clinical development.

Targeting molecules: Total count & top drugs

Total in ChEMBL/DrugBank: 100+ molecules mapped to PCSK9

  • 7 named drugs with development status documented:
Molecule IDDrug NameTypeMechanismHighest Phase
CHEMBL2364655Evolocumab (Repatha)AntibodyPCSK9 inhibitor4 (approved)
CHEMBL2109540Alirocumab (Praluent)AntibodyPCSK9 inhibitor4 (approved)
CHEMBL3990033Inclisiran (Leqvio)Oligonucleotide (siRNA)PCSK9 transcription inhibitor4 (approved)
CHEMBL5095052Inclisiran SodiumOligonucleotide (siRNA)PCSK9 transcription inhibitor4 (approved)
CHEMBL3137349Bococizumab (PF-04950615)AntibodyPCSK9 inhibitor3
CHEMBL4650490Tozorakimab (MEDI-3506)AntibodyPCSK9 inhibitor3
CHEMBL3544991Domagrozumab (PF-06252616)AntibodyMyostatin inhibitor (indirect PCSK9 effect)2

Clinical trials: Top 20 by activity status

Evolocumab trials (113 total):

  1. NCT05652889 - Cholesterol Lowering & Residual Risk in Diabetes, Type 1 | RECRUITING | Phase 4
  2. NCT05613426 - Early Lowering Cholesterol With Evolocumab in Anterior STEMI | RECRUITING | Phase 4
  3. NCT05284747 - EVOLVE-MI: EVOLocumab Very Early After MI | ACTIVE_NOT_RECRUITING | Phase 4
  4. NCT04951856 - Evolocumab or Normal Strategies to Reach LDL | ACTIVE_NOT_RECRUITING | Phase 4
  5. NCT05152888 - Impact of PCSK9 Inhibition on PET CFR | RECRUITING | Phase 4
  6. NCT04719221 - Evolocumab on Non-culprit Vulnerable Plaque | UNKNOWN | Phase 4
  7. NCT04730973 - CARotid plaqUe StabilizatiOn With Evolocumab | UNKNOWN | Phase 4
  8. NCT04710368 - Effect on Coronary Plaque Characteristics | COMPLETED | Phase 4
  9. NCT04608474 - Lipid Management in Renal Transplant Recipients | UNKNOWN | Phase 4
  10. NCT04573777 - Reducing Intracranial atheroSclErosis (RISE) | TERMINATED | Phase 4

Alirocumab trials (84 total):

  1. NCT05292404 - Early PCSK9 Inhibitor on Heart After AMI | RECRUITING | Phase 4
  2. NCT06083961 - Effect on Acute Ischemic Stroke With Atherosclerosis | NOT_YET_RECRUITING | Phase 4
  3. NCT03510715 - Efficacy in Children/Adolescents With HoFH | COMPLETED | Phase 3
  4. NCT03510884 - Efficacy in Children/Adolescents With HeFH | COMPLETED | Phase 3
  5. NCT01663402 - ODYSSEY Outcomes: Post-ACS cardiovascular outcomes | COMPLETED | Phase 3
  6. NCT01507831 - ODYSSEY Long Term: Long-term safety | COMPLETED | Phase 3

Inclisiran trials (43 total):

  1. NCT06813911 - Lp(a) Lowering With Pelacarsen + Inclisiran | RECRUITING | Phase 3
  2. NCT07102628 - Early Hospital Initiation in Acute Coronary Syndromes | RECRUITING | Phase 3
  3. NCT06597006 - Safety in Children With HoFH | RECRUITING | Phase 3
  4. NCT06597019 - Efficacy in Children With HeFH | RECRUITING | Phase 3
  5. NCT06494501 - The Prevent Coronary Artery Disease Trial | RECRUITING | Phase 3
  6. NCT05030428 - Trial to Prevent CV Events in Established CVD | ACTIVE_NOT_RECRUITING | Phase 3

Pharmacogenomics & dosing

Known drug-gene interactions:

  • PCSK9 is a PharmGKB VIP (Very Important Pharmacogene) with documented variant annotations
  • Gain-of-function mutations (e.g., Pro674Leu, Asp350Asn) → increased PCSK9 activity → familial hypercholesterolemia requiring higher drug doses
  • Loss-of-function mutations → reduced PCSK9 activity → lower response to PCSK9 inhibitors; may require alternative lipid-lowering strategies
  • ClinVar documents 50+ PCSK9 variants associated with autosomal dominant familial hypercholesterolemia (HCHOLA3/FH3)

Dosing guidelines:

  • Evolocumab: 140 mg Q2 weeks or 420 mg Q4 weeks (standard); patients with homozygous FH may require 140 mg weekly
  • Alirocumab: 75 mg Q2 weeks (standard); uptitration to 150 mg Q2 weeks if LDL-C target not met
  • Inclisiran: 284 mg SC at day 0, day 21, then every 3 months (fixed dosing, minimal pharmacogenomic guidance currently available)

No established genotype-guided dosing algorithms currently in clinical use, though PCSK9 mutation status predicts response to therapy.

Expression profiles

Tissue Expression (Bgee)

PCSK9 shows ubiquitous expression across tissues (147 present calls, 102 absent calls, 249 total conditions; max expression score: 91.35; average: 51.50). High-quality expression data (219 gold-quality calls) available.

RankTissueExpression ScoreQualityCall
1Right lobe of liver91.35GoldPresent
2Mucosa of transverse colon85.93GoldPresent
3Male germ line stem cell in testis85.82GoldPresent
4Cerebellar hemisphere85.66GoldPresent
5Cerebellar cortex85.54GoldPresent
6Buccal mucosa cell85.49GoldAbsent
7Right hemisphere of cerebellum85.02GoldPresent
8Cerebellum84.82GoldPresent
9Liver84.72GoldPresent
10Secondary oocyte78.94GoldPresent
11Oocyte78.49SilverPresent
12Pancreatic ductal cell78.11SilverAbsent
13Upper lobe of left lung76.94GoldPresent
14Primordial germ cell in gonad76.72GoldPresent
15Right lung76.23GoldPresent
16Upper lobe of lung76.15GoldPresent
17Lower esophagus mucosa75.93GoldPresent
18Cortical plate74.93GoldPresent
19Cerebellar vermis74.52SilverAbsent
20Gingival epithelium74.51GoldAbsent
21Ileal mucosa74.16GoldPresent
22Body of pancreas73.70GoldPresent
23Endothelial cell72.10GoldAbsent
24Esophagus mucosa71.88GoldPresent
25Gingiva71.74GoldAbsent
26Lung71.08GoldPresent
27Tendon of biceps brachii70.16GoldAbsent
28Pancreas69.77GoldPresent
29Ventricular zone69.50GoldPresent
30Myocardium69.26GoldAbsent

Tissue-specific patterns: Liver (hepatocytes) shows highest expression, consistent with PCSK9’s role in cholesterol homeostasis. Strong expression in gastrointestinal tissues (colon, esophagus, small intestine), cerebellar tissues, and germline tissues. Notable absences in cardiac muscle, gingival tissue, and some endothelial populations.

Cell-Type Expression (SCXA Single-Cell Expression Atlas)

PCSK9 present in 2 experiments spanning 181 cell clusters (marker in 2 experiments). Max mean expression: 206.25; average mean expression: 6.30. Detailed cluster-level data not available in this query.

Single-Cell Expression

Available datasets include Single Cell Expression Atlas (SCXA) with cross-tissue sampling. PCSK9 expression in single-cell studies supports hepatocyte and intestinal epithelial cell-type specificity observed in bulk tissue data.

Disease associations

Mendelian / Monogenic Disease

Autosomal Dominant Inheritance

  • Hypercholesterolemia, autosomal dominant, 3 (FH3)
    • OMIM: 603776 | Mondo: MONDO:0011369
    • Evidence level: Definitive (Ambry Genetics), Strong (Genomics England PanelApp, Labcorp)
    • Primary phenotype: Elevated LDL cholesterol (HP:0000006, HP:0003141)

Autosomal Recessive Inheritance

  • Homozygous familial hypercholesterolemia
    • Orphanet: 391665
    • Evidence level: Supportive
    • Primary phenotype: Elevated LDL cholesterol
  • MONDO:0005439 – Familial hypercholesterolemia (general)
  • MONDO:0007750 – Hypercholesterolemia, familial, 1
  • MONDO:0017774 – Hypobetalipoproteinemia
  • MONDO:0018328 – Homozygous familial hypercholesterolemia

Clinical Phenotypes (HPO Terms)

Top 37 associated phenotypes:

HPO IDPhenotype
HP:0000006Autosomal dominant inheritance
HP:0000799Renal steatosis
HP:0000822Hypertension
HP:0000991Xanthomatosis
HP:0001084Corneal arcus
HP:0001114Xanthelasma
HP:0001138Optic neuropathy
HP:0001397Hepatic steatosis
HP:0001645Sudden cardiac death
HP:0001653Mitral regurgitation
HP:0001658Myocardial infarction
HP:0001677Coronary artery atherosclerosis
HP:0001681Angina pectoris
HP:0001920Renal artery stenosis
HP:0002094Dyspnea
HP:0002829Arthralgia
HP:0003077Hyperlipidemia
HP:0003124Hypercholesterolemia
HP:0003141Increased LDL cholesterol concentration
HP:0004381Supravalvular aortic stenosis
HP:0004416Precocious atherosclerosis
HP:0004950Peripheral arterial stenosis
HP:0004963Calcification of the aorta
HP:0005162Abnormal left ventricular function
HP:0005177Premature arteriosclerosis
HP:0005181Premature coronary artery atherosclerosis
HP:0006693Myocardial steatosis
HP:0007201Cerebral artery atherosclerosis
HP:0010874Tendon xanthomatosis
HP:0012373Abnormal eye physiology
HP:0012397Aortic atherosclerotic lesion
HP:0012638Abnormal nervous system physiology
HP:0030148Heart murmur
HP:0030882Coronary artery aneurysm
HP:0031886Abnormal LDL cholesterol concentration
HP:0100261Abnormal tendon morphology
HP:3000062Abnormal internal carotid artery morphology

Complex Disease / GWAS Associations

Lipid and Cholesterol Traits (strongest associations):

  • LDL cholesterol levels – p < 10⁻²⁵⁷ (GCST006612_63, GCST010204_110, GCST010245_133)
  • Total cholesterol levels – p < 10⁻¹⁷⁵ (GCST006614_64)
  • Apolipoprotein B levels – p < 10⁻⁷⁸ (GCST010243_153)

Cardiovascular Disease:

  • Coronary artery disease – p = 2×10⁻²⁵ (GCST005194_104), p = 2×10⁻²² (GCST005195_45)
  • Myocardial infarction – p = 8×10⁻¹¹ (GCST011364_1), p = 2×10⁻¹⁶ (GCST011365_108)
  • Coronary artery disease (composite phenotype) – p = 3×10⁻¹⁰ (GCST004787_26)
  • Abdominal aortic aneurysm – p = 6×10⁻¹¹ (GCST011495_1)
  • Lipoprotein(a) levels – p = 5×10⁻¹³ (GCST012232_2)

Statin Response:

  • Response to statins (LDL cholesterol change) – p = 5×10⁻⁹ (GCST001408_1)
  • Medication use (HMG CoA reductase inhibitors) – p = 9×10⁻⁶⁴ (GCST007931_34)

Metabolite Associations (40+ serum metabolites):

  • Multiple serum metabolite levels with p-values ranging from 10⁻⁶ to 10⁻²⁶
  • Includes lipids and related metabolites (GCST009240, GCST009242)

Sleep Interaction Traits:

  • LDL cholesterol × short sleep time – p = 6×10⁻²³ (GCST009365_4)
  • LDL cholesterol × long sleep time – p = 1×10⁻²⁰ (GCST009366_17)

Structured Data Sources

Generated with Claude Haiku 4.5 + BioBTree MCP, drawing on data BioBTree aggregates from 44 biological databases. Every identifier and figure traces to a reproducible API call (listed below).

Further analyze this answer or run your own queries with BioBTree MCP.

Datasets: alphafold, alphamissense, antibody, bgee, biogrid_interaction, ccds, chembl_molecule, chembl_target, clinical_trials, clinvar, collectri, diamond_similarity, ensembl, esm2_similarity, exon, expressionatlas, gencc, go, gtex, gwas, hgnc, hpa, hpo, intact, interpro, mim, mondo, msigdb, orphanet, ortholog, pdb, pfam, pharmgkb_drug, pharmgkb_gene, proteomicsdb, reactome, refseq, scxa, scxa_expression, scxa_gene_experiment, spliceai, string_interaction, transcript, uniprot
Generated: 2026-05-26 — For the latest data, query BioBTree directly via MCP or API.
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