TAP2 Gene: Function, Mutations, and Associated Diseases | NCBI, UniProt, ClinVar

The TAP2 gene encodes a subunit of the transporter associated with antigen processing (TAP) complex, which is essential for peptide translocation from the cytosol into the endoplasmic reticulum for loading onto MHC class I molecules. TAP2 forms a heterodimer with TAP1, and together they function as an ATP-binding cassette (ABC) transporter. Mutations in TAP2 impair antigen presentation, leading to immunodeficiency syndromes such as bare lymphocyte syndrome type I and increased susceptibility to infections and autoimmune conditions.

Tissue Expression

Cell Line Expression

Hotspot Mutations

Mutation functional classification

• Antigen processing and presentation (KEGG hsa04612)

• MHC class I antigen presentation (Reactome R-HSA-983170)

TAP2 is a 703-amino acid ABC transporter subunit that, together with TAP1, forms a heterodimeric peptide transporter in the endoplasmic reticulum membrane. It contains a transmembrane domain (TMD) and a nucleotide-binding domain (NBD). ATP binding and hydrolysis drive conformational changes that allow peptide translocation. TAP2 is essential for loading antigenic peptides onto MHC class I molecules, a critical step in adaptive immunity.