Seroatlas · Human Serome Atlas

TBC1D8B

TBC1 domain family member 8B

Also known as: FLJ20298, GRAMD8B, RP11-321G1.1, TBC8B_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q0IIM8
Gene
TBC1D8B
Ensembl
ENSG00000133138
Chromosome
X
Canonical length
1120 aa
Protein class
Disease related genes, Human disease related genes, Predicted intracellular proteins
Subcellular location
Cytosol

OverviewNCBI Gene

This gene encodes a protein with a TBC (Tre-2/Bub2/CDC16) domain. Some mammalian proteins with this domain have been shown to function as Rab-GAPs by binding to specific Rab proteins and affecting their GTPase activity. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Sep 2011]

Canonical amino-acid sequenceUniProt

1120 residues, UniProt reviewed canonical sequence.

>Q0IIM8|TBC1D8B
     1  MWLKPEEVLL KNALKLWLME RSNDYFVLQR RRGYGEEGGG GLTGLLVGTL DSVLDSTAKV
    61  APFRILHQTP DSQVYLSIAC GANREEITKH WDWLEQNIMK TLSVFDSNED ITNFVQGKIR
   121  GLIAEEGKHC FAKEDDPEKF REALLKFEKC FGLPEKEKLV TYYSCSYWKG RVPCQGWLYL
   181  STNFLSFYSF LLGSEIKLII SWDEVSKLEK TSNVILTESI HVCSQGENHY FSMFLHINQT
   241  YLLMEQLANY AIRRLFDKET FDNDPVLYNP LQITKRGLEN RAHSEQFNAF FRLPKGESLK
   301  EVHECFLWVP FSHFNTHGKM CISENYICFA SQDGNQCSVI IPLREVLAID KTNDSSKSVI
   361  ISIKGKTAFR FHEVKDFEQL VAKLRLRCGA ASTQYHDIST ELAISSESTE PSDNFEVQSL
   421  TSQRECSKTV NTEALMTVFH PQNLETLNSK MLKEKMKEQS WKILFAECGR GVSMFRTKKT
   481  RDLVVRGIPE TLRGELWMLF SGAVNDMATN PDYYTEVVEQ SLGTCNLATE EIERDLRRSL
   541  PEHPAFQSDT GISALRRVLT AYAYRNPKIG YCQAMNILTS VLLLYAKEEE AFWLLVAVCE
   601  RMLPDYFNRR IIGALVDQAV FEELIRDHLP QLTEHMTDMT FFSSVSLSWF LTLFISVLPI
   661  ESAVNVVDCF FYDGIKAILQ LGLAILDYNL DKLLTCKDDA EAVTALNRFF DNVTNKDSPL
   721  PSNVQQGSNV SDEKTSHTRV DITDLIRESN EKYGNIRYED IHSMRCRNRL YVIQTLEETT
   781  KQNVLRVVSQ DVKLSLQELD ELYVIFKKEL FLSCYWCLGC PVLKHHDPSL PYLEQYQIDC
   841  QQFRALYHLL SPWAHSANKD SLALWTFRLL DENSDCLINF KEFSSAIDIM YNGSFTEKLK
   901  LLFKLHIPPA YTEVKSKDAS KGDELSKEEL LYFSQLHVSK PANEKEAESA KHSPEKGKGK
   961  IDIQAYLSQW QDELFKKEEN IKDLPRMNQS QFIQFSKTLY NLFHEDPEEE SLYQAIAVVT
  1021  SLLLRMEEVG RKLHSPTSSA KGFSGTVCGS GGPSEEKTGS HLEKDPCSFR EEPQWSFAFE
  1081  QILASLLNEP ALVRFFEKPI DVKAKLENAR ISQLRSRTKM

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against TBC1D8B 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)
0.3
Highest tissue expression
18 nTPM

Expression across tissuesHPA

Tissue

  • adrenal gland: 18 nTPM
  • liver: 11 nTPM
  • stomach: 10 nTPM
  • epididymis: 8.9 nTPM
  • choroid plexus: 8.7 nTPM
  • small intestine: 8.6 nTPM

Single-cell type

  • corticotrophs: 148 nCPM
  • choroid plexus epithelial cells: 130 nCPM
  • sertoli cells: 128 nCPM
  • adrenal cortex cells: 128 nCPM
  • gonadotrophs: 117 nCPM
  • somatotrophs: 102 nCPM

Immune cell

  • basophil: 1.3 nTPM
  • naive B-cell: 1 nTPM
  • neutrophil: 1 nTPM
  • plasmacytoid DC: 0.7 nTPM
  • memory B-cell: 0.6 nTPM
  • classical monocyte: 0.5 nTPM

Brain region

  • white matter: 89 nTPM
  • choroid plexus: 89 nTPM
  • cerebral cortex: 82 nTPM
  • cerebellum: 78 nTPM
  • hippocampal formation: 69 nTPM
  • basal ganglia: 65 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about TBC1D8B.

Disease | AllUniProt

Conditions TBC1D8B is implicated in, by any mechanism.

Disease | GeneticClinVar

10 pathogenic / likely-pathogenic of 467 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Nephrotic syndrome, type 20

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)
0.74
gnomAD pLI
0
gnomAD missense Z
0.06
DepMap mean gene effect
-0.01
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 TBC1D8B as an antibody target. Whether an autoantibody or antibody against TBC1D8B could matter depends on whether native TBC1D8B is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

TBC1D8B 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 TBC1D8B as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/TBC1D8B. 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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