HLA class II histocompatibility antigen, DM beta chain (MHC class II antigen DMB,Really interesting new gene 7 protein)
HLA-DMB belongs to the HLA class II beta chain paralogues. This class II molecule is a heterodimer consisting of an alpha (DMA) and a beta (DMB) chain, both anchored in the membrane. It is located in intracellular vesicles. DM plays a central role in the peptide loading of MHC class II molecules by helping to release the CLIP (class II-associated invariant chain peptide) molecule from the peptide binding site. Class II molecules are expressed in antigen presenting cells (APC: B lymphocytes, dendritic cells, macrophages). The beta chain is approximately 26-28 kDa and its gene contains 6 exons. Exon one encodes the leader peptide, exons 2 and 3 encode the two extracellular domains, exon 4 encodes the transmembrane domain and exon 5 encodes the cytoplasmic tail. [provided by RefSeq, Jul 2008],domain:The YXXZ (Tyr-Xaa-Xaa-Zaa, where Zaa is a hydrophobic residue) motif mediates the targeting to the lysosomal compartments.,function:Plays a critical role in catalyzing the release of class II HLA-associated invariant chain-derived peptides (CLIP) from newly synthesized class II HLA molecules and freeing the peptide binding site for acquisition of antigenic peptides.,polymorphism:The following alleles of DMB are known: DMB*0101, DMB*0102, DMB*0103, DMB*0104 (DMB3.4), DMB*0105 and DMB*0106. The sequence shown is that of DMB*0101.,similarity:Belongs to the MHC class II family.,similarity:Contains 1 Ig-like C1-type (immunoglobulin-like) domain.,subcellular location:Localizes to late endocytic compartment. Associates with lysosome membranes.,subunit:Heterodimer of an alpha chain (DMA) and a beta chain (DMB).,
