HM13 cDNA Clone – Histocompatibility (Minor) 13 (Human)

The protein encoded by this gene, which localizes to the endoplasmic reticulum, catalyzes intramembrane proteolysis of some signal peptides after they have been cleaved from a preprotein. This activity is required to generate signal sequence-derived human lymphocyte antigen-E epitopes that are recognized by the immune system, and to process hepatitis C virus core protein. The encoded protein is an integral membrane protein with sequence motifs characteristic of the presenilin-type aspartic proteases. Multiple transcript variants encoding several different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

HM13: Catalyzes intramembrane proteolysis of some signal peptides after they have been cleaved from a preprotein, resulting in the release of the fragment from the ER membrane into the cytoplasm. Required to generate lymphocyte cell surface (HLA-E) epitopes derived from MHC class I signal peptides. May play a role in graft rejection. May be necessary for the removal of the signal peptide that remains attached to the hepatitis C virus core protein after the initial proteolytic processing of the polyprotein. Involved in the intramembrane cleavage of the integral membrane protein PSEN1. Belongs to the peptidase A22B family. 4 isoforms of the human protein are produced by alternative splicing.

Protein type: Membrane protein, integral; Endoplasmic reticulum; EC 3.4.23.-; Protease; Membrane protein, multi-pass

Chromosomal Location of Human Ortholog: 20q11.21

Cellular Component: cell surface; endoplasmic reticulum; endoplasmic reticulum membrane; lysosomal membrane; membrane; rough endoplasmic reticulum

Molecular Function: aspartic endopeptidase activity, intramembrane cleaving; peptidase activity; protein binding; protein homodimerization activity; ubiquitin protein ligase binding

Biological Process: membrane protein ectodomain proteolysis; membrane protein intracellular domain proteolysis; membrane protein proteolysis; protein homotetramerization; signal peptide processing