TAPBP

Protein identityUniProt · HPA

UniProt accession

O15533

Gene

TAPBP

Ensembl

ENSG00000231925

Chromosome

6

Canonical length

448 aa

Protein class

Disease related genes, Human disease related genes, Plasma proteins, Potential drug targets, Predicted intracellular proteins, Predicted membrane proteins, Transporters

Subcellular location

Nucleoli,Plasma membrane,Mitochondria

OverviewNCBI Gene

This gene encodes a transmembrane glycoprotein which mediates interaction between newly assembled major histocompatibility complex (MHC) class I molecules and the transporter associated with antigen processing (TAP), which is required for the transport of antigenic peptides across the endoplasmic reticulum membrane. This interaction is essential for optimal peptide loading on the MHC class I molecule. Up to four complexes of MHC class I and this protein may be bound to a single TAP molecule. This protein contains a C-terminal double-lysine motif (KKKAE) known to maintain membrane proteins in the endoplasmic reticulum. This gene lies within the major histocompatibility complex on chromosome 6. Alternative splicing results in three transcript variants encoding different isoforms. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

448 residues, UniProt reviewed canonical sequence.

>O15533|TAPBP
     1  MKSLSLLLAV ALGLATAVSA GPAVIECWFV EDASGKGLAK RPGALLLRQG PGEPPPRPDL
    61  DPELYLSVHD PAGALQAAFR RYPRGAPAPH CEMSRFVPLP ASAKWASGLT PAQNCPRALD
   121  GAWLMVSISS PVLSLSSLLR PQPEPQQEPV LITMATVVLT VLTHTPAPRV RLGQDALLDL
   181  SFAYMPPTSE AASSLAPGPP PFGLEWRRQH LGKGHLLLAA TPGLNGQMPA AQEGAVAFAA
   241  WDDDEPWGPW TGNGTFWLPT VQPFQEGTYL ATIHLPYLQG QVTLELAVYK PPKVSLMPAT
   301  LARAAPGEAP PELLCLVSHF YPSGGLEVEW ELRGGPGGRS QKAEGQRWLS ALRHHSDGSV
   361  SLSGHLQPPP VTTEQHGARY ACRIHHPSLP ASGRSAEVTL EVAGLSGPSL EDSVGLFLSA
   421  FLLLGLFKAL GWAAVYLSTC KDSKKKAE

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against TAPBP 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

1

Mean surface accessibility (rSASA)

0.33

Highest tissue expression

68 nTPM

Expression across tissuesHPA

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about TAPBP.

Disease | AllUniProt

Conditions TAPBP is implicated in, by any mechanism.

• MHC class I deficiency 3 (MHC1D3) MIM:620814

Disease | GeneticClinVar

2 pathogenic / likely-pathogenic of 396 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

• MHC class I deficiency 3

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)

1.18

gnomAD pLI

0

gnomAD missense Z

0.76

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

• antigen processing and presentation of endogenous peptide antigen via MHC class I
• antigen processing and presentation of exogenous peptide antigen via MHC class I, TAP-dependent
• peptide antigen assembly with MHC class I protein complex
• protein-containing complex assembly
• regulation of gene expression
• regulation of protein complex stability
• retrograde vesicle-mediated transport, Golgi to endoplasmic reticulum
• MHC class Ib protein complex assembly
• peptide antigen stabilization

Molecular functions

• MHC class I protein binding
• MHC class I protein complex binding
• molecular adaptor activity
• peptide antigen binding
• protein folding chaperone
• TAP complex binding
• TAP1 binding
• TAP2 binding
• unfolded protein binding

Cellular components

• endoplasmic reticulum
• endoplasmic reticulum membrane
• endoplasmic reticulum-Golgi intermediate compartment membrane
• Golgi membrane
• lumenal side of endoplasmic reticulum membrane
• MHC class I peptide loading complex
• phagocytic vesicle membrane
• Tapasin-ERp57 complex

Protein domainsUniProt · Pfam · InterPro

• Immunoglobulin C1-set
• Immunoglobulin-like domain
• Immunoglobulin-like fold
• Immunoglobulin-like domain superfamily
• Immune Recognition and Response Modulators
• Immunoglobulin C1-set domain
• Tapasin

KeywordsUniProt

• Disulfide bond
• Endoplasmic reticulum
• Glycoprotein
• Immunoglobulin domain
• Membrane
• Signal
• Transmembrane
• Transmembrane helix

InteractionsUniProt · HPA

Protein binding partners of TAPBP in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

• MR1
• TAP1