HM13

Description

The HM13 (histocompatibility minor 13) is a protein-coding gene located on chromosome 20.

The HM13 gene encodes a protein known as Minor histocompatibility antigen H13, which is a nonamer peptide. This peptide is generated by the proteasome in the cytosol and is transported to the ER lumen by the transporter associated with antigen processing (TAP). It is presented on the cell surface by H2-Db major histocompatibility antigen I (MHC I) molecules. A polymorphism in the peptide, Val/Ile, is associated with alloreactivity, leading to transplant rejection in mice. The HM13 gene is the human orthologue of the mouse gene H13. The HM13 gene encodes the signal peptide peptidase (SPP), an ER-resident intramembrane protease. SPP is localized to the ER and catalyzes intramembrane proteolysis of some signal peptides after they have been cleaved from a preprotein. This activity is essential for the generation of signal sequence-derived human lymphocyte antigen-E epitopes, recognized by the immune system, and for processing hepatitis C virus core protein. HM13 is an integral membrane protein with sequence motifs characteristic of the presenilin-type aspartic proteases.

HM13 catalyzes the intramembrane proteolysis of signal peptides after they are cleaved from a preprotein, leading to the release of the fragment from the ER membrane into the cytoplasm. This process is essential for the generation of HLA-E epitopes derived from MHC class I signal peptides, and may also be involved in removing the signal peptide attached to the hepatitis C virus core protein. HM13 is involved in the intramembrane cleavage of PSEN1, and cleaves XBP1 isoform 1 in a DERL1/RNF139-dependent manner. It may play a role in graft rejection.

HM13 is also known as H13, IMP1, IMPAS, IMPAS-1, MSTP086, PSENL3, PSL3, SPP, SPPL1.

Associated Diseases

WES Whole Exome Sequencing