Rabbit anti-Human MR1 Polyclonal Antibody

Uniprot Id

Q95460

Target Species

Human

Target Name

MR1

Target Full Name

Major histocompatibility complex class I-related gene protein

Target Function

Antigen-presenting molecule specialized in displaying microbial pyrimidine-based metabolites to alpha-beta T cell receptors (TCR) on innate-type mucosal-associated invariant T (MAIT) cells. In complex with B2M preferentially presents riboflavin-derived metabolites to semi-invariant TRAV1-2 TCRs on MAIT cells, guiding immune surveillance of the microbial metabolome at mucosal epithelial barriers. Signature pyrimidine-based microbial antigens are generated via non-enzymatic condensation of metabolite intermediates of the riboflavin pathway with by-products arising from other metabolic pathways such as glycolysis. Typical potent antigenic metabolites are 5-(2-oxoethylideneamino)-6-D-ribitylaminouracil (5-OE-RU) and 5-(2-oxopropylideneamino)-6-D-ribitylaminouracil (5-OP-RU), products of condensation of 5-amino-6-D-ribityaminouracil (5-A-RU) with glyoxal or methylglyoxal by-products, respectively. May present microbial antigens to various TRAV1-2-negative MAIT cell subsets, providing for unique recognition of diverse microbes, including pathogens that do not synthesize riboflavin. Upon antigen recognition, elicits rapid innate-type MAIT cell activation to eliminate pathogenic microbes by directly killing infected cells. During T cell development, drives thymic selection and post-thymic terminal differentiation of MAIT cells in a process dependent on commensal microflora. Acts as an immune sensor of cancer cell metabolome. May present a tumor-specific or -associated metabolite essential for cancer cell survival to a pan-cancer TCR consisting of TRAV38.2-DV8*TRAJ31 alpha chain paired with a TRBV25.1*TRBJ2.3 beta chain on a non-MAIT CD8-positive T cell clone (MC.7.G5), triggering T cell-mediated killing of a wide range of cancer cell types.

Target Subcellular Location

Cell membrane; Single-pass type I membrane protein. Endoplasmic reticulum membrane; Single-pass type I membrane protein. Golgi apparatus membrane; Single-pass type I membrane protein. Early endosome membrane; Single-pass type I membrane protein. Late endosome membrane; Single-pass type I membrane protein.; [Isoform 1]: Cell membrane; Single-pass type I membrane protein. Endoplasmic reticulum membrane; Single-pass membrane protein.; [Isoform 3]: Cell membrane; Single-pass type I membrane protein. Endoplasmic reticulum membrane; Single-pass membrane protein.; [Isoform 4]: Secreted.

Target Protein Families

MHC class I family

Target Tissue Specificity

Ubiquitous. Low expression is detected in peripheral blood B cells, T cells, monocytes and in bronchial epithelial cells (at protein level). Expressed in plasmablasts or plasma B cells in the lamina propria of ileum, appendix and colon (at protein level).

Target Synonyms

Class I histocompatibility antigen like protein; Class I histocompatibility antigen-like protein; HLALS; HMR1_HUMAN; Major histocompatibility complex class I like sequence; Major histocompatibility complex class I related; Major histocompatibility complex class I related gene protein; Major histocompatibility complex class I related isoform CRA a; Major histocompatibility complex class I related isoform CRA c; Major histocompatibility complex class I related isoform CRA d; Major histocompatibility complex class I-related gene protein; MHC class I like antigen MR 1; MHC class I like antigen MR1; MHC class I related gene protein; MHC class I related protein 1 isoform B; MHC class I related protein 1 isoform C; MHC class I-related gene protein; MR 1; Mr1; Mr1 protein; MR1B; MR1C

Target Background

MAIT (mucosal-associated invariant T-cells) lymphocytes represent a small population of T-cells primarily found in the gut. The protein encoded by this gene is an antigen-presenting molecule that presents metabolites of microbial vitamin B to MAITs. This presentation may activate the MAITs to regulate the amounts of specific types of bacteria in the gut. Several transcript variants encoding different isoforms have been found for this gene, and a pseudogene of it has been detected about 36 kbp upstream on the same chromosome.