Seroatlas · Human Serome Atlas

CROT

Peroxisomal carnitine O-octanoyltransferase

Also known as: COT, OCTC_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9UKG9
Gene
CROT
Ensembl
ENSG00000005469
Chromosome
7
Canonical length
612 aa
Protein class
Enzymes, Metabolic proteins, Plasma proteins, Predicted intracellular proteins, Transporters
Subcellular location
Vesicles

OverviewNCBI Gene

This gene encodes a member of the carnitine/choline acetyltransferase family. The encoded protein converts 4,8-dimethylnonanoyl-CoA to its corresponding carnitine ester. This transesterification occurs in the peroxisome and is necessary for transport of medium- and long- chain acyl-CoA molecules out of the peroxisome to the cytosol and mitochondria. The protein thus plays a role in lipid metabolism and fatty acid beta-oxidation. Alternatively spliced transcript variants have been described.[provided by RefSeq, Jan 2009]

Canonical amino-acid sequenceUniProt

612 residues, UniProt reviewed canonical sequence.

>Q9UKG9|CROT
     1  MENQLAKSTE ERTFQYQDSL PSLPVPSLEE SLKKYLESVK PFANQEEYKK TEEIVQKFQS
    61  GIGEKLHQKL LERAKGKRNW LEEWWLNVAY LDVRIPSQLN VNFAGPAAHF EHYWPPKEGT
   121  QLERGSITLW HNLNYWQLLR KEKVPVHKVG NTPLDMNQFR MLFSTCKVPG ITRDSIMNYF
   181  RTESEGRSPN HIVVLCRGRA FVFDVIHEGC LVTPPELLRQ LTYIHKKCHS EPDGPGIAAL
   241  TSEERTRWAK AREYLIGLDP ENLALLEKIQ SSLLVYSMED SSPHVTPEDY SEIIAAILIG
   301  DPTVRWGDKS YNLISFSNGV FGCNCDHAPF DAMIMVNISY YVDEKIFQNE GRWKGSEKVR
   361  DIPLPEELIF IVDEKVLNDI NQAKAQYLRE ASDLQIAAYA FTSFGKKLTK NKMLHPDTFI
   421  QLALQLAYYR LHGHPGCCYE TAMTRHFYHG RTETMRSCTV EAVRWCQSMQ DPSVNLRERQ
   481  QKMLQAFAKH NKMMKDCSAG KGFDRHLLGL LLIAKEEGLP VPELFTDPLF SKSGGGGNFV
   541  LSTSLVGYLR VQGVVVPMVH NGYGFFYHIR DDRFVVACSA WKSCPETDAE KLVQLTFCAF
   601  HDMIQLMNST HL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CROT 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
Intracellular
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.2
Highest tissue expression
38 nTPM

Expression across tissuesHPA

Tissue

  • thyroid gland: 38 nTPM
  • retina: 33 nTPM
  • liver: 33 nTPM
  • duodenum: 30 nTPM
  • seminal vesicle: 26 nTPM
  • urinary bladder: 24 nTPM

Single-cell type

  • cytotrophoblasts: 223 nCPM
  • prostatic hillock cells: 182 nCPM
  • urothelial cells: 164 nCPM
  • basal prostatic cells: 149 nCPM
  • rod photoreceptor cells: 120 nCPM
  • papillary tip epithelial cells: 114 nCPM

Immune cell

  • NK-cell: 13 nTPM
  • MAIT T-cell: 8.7 nTPM
  • memory CD4 T-cell: 6.7 nTPM
  • gdT-cell: 6.6 nTPM
  • non-classical monocyte: 6.3 nTPM
  • T-reg: 6.2 nTPM

Brain region

  • choroid plexus: 15 nTPM
  • basal ganglia: 11 nTPM
  • cerebellum: 10 nTPM
  • cerebral cortex: 10 nTPM
  • white matter: 9.4 nTPM
  • hypothalamus: 8.9 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)
1.17
gnomAD pLI
0
gnomAD missense Z
0
DepMap mean gene effect
0.06
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 8% 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 CROT as an antibody target. Whether an autoantibody or antibody against CROT could matter depends on whether native CROT is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CROT 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 CROT as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CROT. 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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