Beta 2 Microglobulin (B2M) Native Protein

This gene encodes a serum protein found in association with the major histocompatibility complex (MHC) class I heavy chain on the surface of nearly all nucleated cells. The protein has a predominantly beta-pleated sheet structure that can form amyloid fibrils in some pathological conditions. The encoded antimicrobial protein displays antibacterial activity in amniotic fluid. A mutation in this gene has been shown to result in hypercatabolic hypoproteinemia.[provided by RefSeq, Aug 2014]

B2M: Component of the class I major histocompatibility complex (MHC). Involved in the presentation of peptide antigens to the immune system. Heterodimer of an alpha chain and a beta chain. Beta-2- microglobulin is the beta-chain of major histocompatibility complex class I molecules. Polymers of beta 2-microglobulin can be found in tissues from patients on long-term hemodialysis. Belongs to the beta-2-microglobulin family.

Protein type: Secreted, signal peptide; Secreted

Chromosomal Location of Human Ortholog: 15q21.1

Cellular Component: Golgi membrane; Golgi apparatus; extracellular space; phagocytic vesicle membrane; focal adhesion; membrane; early endosome membrane; endoplasmic reticulum lumen; cytoplasm; extracellular region; plasma membrane; MHC class I protein complex; external side of plasma membrane

Molecular Function: identical protein binding; protein binding

Biological Process: response to drug; regulation of immune response; viral reproduction; positive regulation of T cell mediated cytotoxicity; antigen processing and presentation of exogenous peptide antigen via MHC class I, TAP-independent; cytokine and chemokine mediated signaling pathway; T cell differentiation in the thymus; antigen processing and presentation of exogenous peptide antigen via MHC class I, TAP-dependent; regulation of defense response to virus by virus; retinal homeostasis; antigen processing and presentation of peptide antigen via MHC class I; iron ion homeostasis; response to cadmium ion; response to molecule of bacterial origin; antigen processing and presentation of exogenous peptide antigen via MHC class I; innate immune response; protein refolding; antigen processing and presentation of exogenous protein antigen via MHC class Ib, TAP-dependent

Disease: Hypoproteinemia, Hypercatabolic