TAP2 : transporter 2, ATP binding cassette subfamily B member
Description
The TAP2 (transporter 2, ATP binding cassette subfamily B member) is a protein-coding gene located on chromosome 6.
The TAP2 gene provides instructions for making a protein that plays a crucial role in the immune system. It combines with the TAP1 protein to create the TAP complex, located within the ER membrane. This complex transports protein fragments from foreign invaders into the ER, where they attach to MHC class I proteins. These MHC class I proteins are then transported to the cell surface, enabling immune cells to recognize and respond to the foreign invaders.
The TAP2 protein, along with its partner protein TAP1, forms the transporter associated with antigen processing (TAP) complex. This complex acts as a molecular pump, actively transporting peptide fragments derived from foreign invaders from the cytosol into the endoplasmic reticulum (ER). The energy for this transport is provided by ATP hydrolysis. TAP2 specifically transports peptides with 8 to 13 amino acids, exhibiting a preference for peptides with a hydrophobic residue at position 3 and hydrophobic or charged residues at the C-terminus. Once inside the ER, these peptides are loaded onto MHC class I molecules, ultimately leading to the presentation of these foreign antigens on the cell surface. This process triggers an immune response against the invaders.
TAP2 is also known as ABC18, ABCB3, APT2, D6S217E, MHC1D2, PSF-2, PSF2, RING11.
