Seroatlas · Human Serome Atlas

TBC1D20

TBC1 domain family member 20

Also known as: C20orf140, dJ852M4.2, TBC20_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q96BZ9
Gene
TBC1D20
Ensembl
ENSG00000125875
Chromosome
20
Canonical length
403 aa
Protein class
Disease related genes, Human disease related genes, Predicted membrane proteins

OverviewNCBI Gene

This gene encodes a protein that belongs to a family of GTPase activator proteins of Rab-like small GTPases. The encoded protein and its cognate GTPase, Rab1, bind the nonstructural protein 5A (NS5A) of the hepatitis C virus (HCV) to mediate viral replication. Depletion of this protein inhibits replication of the virus and HCV infection. Mutations in this gene are associated with Warburg micro syndrome 4. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Mar 2014]

Canonical amino-acid sequenceUniProt

403 residues, UniProt reviewed canonical sequence.

>Q96BZ9|TBC1D20
     1  MALRSAQGDG PTSGHWDGGA EKADFNAKRK KKVAEIHQAL NSDPTDVAAL RRMAISEGGL
    61  LTDEIRRKVW PKLLNVNAND PPPISGKNLR QMSKDYQQVL LDVRRSLRRF PPGMPEEQRE
   121  GLQEELIDII LLILERNPQL HYYQGYHDIV VTFLLVVGER LATSLVEKLS THHLRDFMDP
   181  TMDNTKHILN YLMPIIDQVN PELHDFMQSA EVGTIFALSW LITWFGHVLS DFRHVVRLYD
   241  FFLACHPLMP IYFAAVIVLY REQEVLDCDC DMASVHHLLS QIPQDLPYET LISRAGDLFV
   301  QFPPSELARE AAAQQQAERT AASTFKDFEL ASAQQRPDMV LRQRFRGLLR PEDRTKDVLT
   361  KPRTNRFVKL AVMGLTVALG AAALAVVKSA LEWAPKFQLQ LFP

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against TBC1D20 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
2
Mean surface accessibility (rSASA)
0.35
Highest tissue expression
23 nTPM

Expression across tissuesHPA

Tissue

  • adrenal gland: 23 nTPM
  • cerebellum: 22 nTPM
  • skeletal muscle: 22 nTPM
  • tongue: 22 nTPM
  • skin: 22 nTPM
  • esophagus: 21 nTPM

Single-cell type

  • platelets: 318 nCPM
  • late spermatids: 228 nCPM
  • esophageal apical cells: 223 nCPM
  • syncytiotrophoblasts: 100 nCPM
  • breast lactating cells: 68 nCPM
  • late primary spermatocytes: 66 nCPM

Immune cell

  • basophil: 3.1 nTPM
  • memory CD8 T-cell: 2.1 nTPM
  • gdT-cell: 1.8 nTPM
  • naive CD8 T-cell: 1.8 nTPM
  • neutrophil: 1.7 nTPM
  • MAIT T-cell: 1.2 nTPM

Brain region

  • basal ganglia: 20 nTPM
  • midbrain: 20 nTPM
  • medulla oblongata: 19 nTPM
  • white matter: 19 nTPM
  • thalamus: 19 nTPM
  • cerebellum: 18 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about TBC1D20.

Disease | AllUniProt

Conditions TBC1D20 is implicated in, by any mechanism.

Disease | GeneticClinVar

8 pathogenic / likely-pathogenic of 190 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

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)
0.36
gnomAD pLI
0.93
gnomAD missense Z
1.21
DepMap mean gene effect
-0.07
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 11% 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 TBC1D20 as an antibody target. Whether an autoantibody or antibody against TBC1D20 could matter depends on whether native TBC1D20 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

TBC1D20 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 TBC1D20 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/TBC1D20. 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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