Seroatlas · Human Serome Atlas

CYP3A43

Cytochrome P450 3A43

Also known as: CP343_HUMAN

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
Q9HB55
Gene
CYP3A43
Ensembl
ENSG00000021461
Chromosome
7
Canonical length
503 aa
Protein class
Enzymes, Metabolic proteins, Plasma proteins, Predicted intracellular proteins, Predicted membrane proteins
Subcellular location
Vesicles,Cytosol

OverviewNCBI Gene

This gene encodes a member of the cytochrome P450 superfamily of enzymes. The cytochrome P450 proteins are monooxygenases which catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids and other lipids. The encoded protein has a low level of testosterone hydroxylase activity, and may play a role in aging mechanisms and cancer progression. This gene is part of a cluster of cytochrome P450 genes on chromosome 7q21.1. Alternate splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Jul 2013]

Canonical amino-acid sequenceUniProt

503 residues, UniProt reviewed canonical sequence.

>Q9HB55|CYP3A43
     1  MDLIPNFAME TWVLVATSLV LLYIYGTHSH KLFKKLGIPG PTPLPFLGTI LFYLRGLWNF
    61  DRECNEKYGE MWGLYEGQQP MLVIMDPDMI KTVLVKECYS VFTNQMPLGP MGFLKSALSF
   121  AEDEEWKRIR TLLSPAFTSV KFKEMVPIIS QCGDMLVRSL RQEAENSKSI NLKDFFGAYT
   181  MDVITGTLFG VNLDSLNNPQ DPFLKNMKKL LKLDFLDPFL LLISLFPFLT PVFEALNIGL
   241  FPKDVTHFLK NSIERMKESR LKDKQKHRVD FFQQMIDSQN SKETKSHKAL SDLELVAQSI
   301  IIIFAAYDTT STTLPFIMYE LATHPDVQQK LQEEIDAVLP NKAPVTYDAL VQMEYLDMVV
   361  NETLRLFPVV SRVTRVCKKD IEINGVFIPK GLAVMVPIYA LHHDPKYWTE PEKFCPERFS
   421  KKNKDSIDLY RYIPFGAGPR NCIGMRFALT NIKLAVIRAL QNFSFKPCKE TQIPLKLDNL
   481  PILQPEKPIV LKVHLRDGIT SGP

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CYP3A43 can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Other membrane
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.24
Highest tissue expression
39 nTPM

Expression across tissuesHPA

Tissue

  • liver: 39 nTPM
  • pancreas: 4.4 nTPM
  • testis: 0.7 nTPM
  • prostate: 0.5 nTPM
  • retina: 0.5 nTPM
  • cerebral cortex: 0.4 nTPM

Single-cell type

  • hepatocytes: 67 nCPM
  • prostatic glandular cells: 16 nCPM
  • retinal ganglion cells: 12 nCPM
  • early spermatids: 8.1 nCPM
  • late primary spermatocytes: 7.9 nCPM
  • late spermatids: 5.1 nCPM

Immune cell

  • basophil: 0.2 nTPM
  • neutrophil: 0.2 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM

Brain region

  • cerebral cortex: 2.7 nTPM
  • white matter: 2.4 nTPM
  • basal ganglia: 1.8 nTPM
  • hippocampal formation: 1.7 nTPM
  • amygdala: 1.5 nTPM
  • thalamus: 1.5 nTPM

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
1.11
gnomAD pLI
0
gnomAD missense Z
0.15
DepMap mean gene effect
-0.16
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 5% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads CYP3A43 as an antibody target. Whether an autoantibody or antibody against CYP3A43 could matter depends on whether native CYP3A43 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CYP3A43 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label CYP3A43 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CYP3A43. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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