Names & Taxonomy
- Uniprot ID:
- P04229
- Entry Name:
- 2B11_HUMAN
- Status:
- reviewed
- Protein Names:
- HLA class II histocompatibility antigen, DRB1-1 beta chain (MHC class II antigen DRB1*1) (DR-1) (DR1)
- Gene Names:
- HLA-DRB1
- Gene Names Primary:
- HLA-DRB1
- Organism:
- Homo sapiens (Human)
Structure
- Length:
- 266
- Sequence:
- MVCLKLPGGSCMTALTVTLMVLSSPLALAGDTRPRFLWQLKFECHFFNGTERVRLLERCIYNQEESVRFDSDVGEYRAVTELGRPDAEYWNSQKDLLEQRRAAVDTYCRHNYGVGESFTVQRRVEPKVTVYPSKTQPLQHHNLLVCSVSGFYPGSIEVRWFRNGQEEKAGVVSTGLIQNGDWTFQTLVMLETVPRSGEVYTCQVEHPSVTSPLTVEWRARSESAQSKMLSGVGGFVLGLLFLGAGLFIYFRNQKGHSGLQPTGFLS
- Proteomes:
- UP000005640
Subcellular location
- Subcellular Location:
- Cell membrane
Function
- Function:
- Binds peptides derived from antigens that access the endocytic route of antigen presenting cells (APC) and presents them on the cell surface for recognition by the CD4 T-cells. The peptide binding cleft accommodates peptides of 10-30 residues. The peptides presented by MHC class II molecules are generated mostly by degradation of proteins that access the endocytic route; where they are processed by lysosomal proteases and other hydrolases. Exogenous antigens that have been endocytosed by the APC are thus readily available for presentation via MHC II molecules; and for this reason this antigen presentation pathway is usually referred to as exogenous. As membrane proteins on their way to degradation in lysosomes as part of their normal turn-over are also contained in the endosomal/lysosomal compartments; exogenous antigens must compete with those derived from endogenous components. Autophagy is also a source of endogenous peptides; autophagosomes constitutively fuse with MHC class II loading compartments. In addition to APCs; other cells of the gastrointestinal tract; such as epithelial cells; express MHC class II molecules and CD74 and act as APCs; which is an unusual trait of the GI tract. To produce a MHC class II molecule that presents an antigen; three MHC class II molecules (heterodimers of an alpha and a beta chain) associate with a CD74 trimer in the ER to form a heterononamer. Soon after the entry of this complex into the endosomal/lysosomal system where antigen processing occurs; CD74 undergoes a sequential degradation by various proteases; including CTSS and CTSL; leaving a small fragment termed CLIP (class-II-associated invariant chain peptide). The removal of CLIP is facilitated by HLA-DM via direct binding to the alpha-beta-CLIP complex so that CLIP is released. HLA-DM stabilizes MHC class II molecules until primary high affinity antigenic peptides are bound. The MHC II molecule bound to a peptide is then transported to the cell membrane surface. In B-cells; the interaction between HLA-DM and MHC class II molecules is regulated by HLA-DO. Primary dendritic cells (DCs) also to express HLA-DO. Lysosomal microenvironment has been implicated in the regulation of antigen loading into MHC II molecules; increased acidification produces increased proteolysis and efficient peptide loading.; (Microbial infection) Acts as a receptor for Epstein-Barr virus on lymphocytes.
- Cross Reference Drug Bank:
- DB05259
- Gene Ontology Go:
- clathrin-coated endocytic vesicle membrane
endocytic vesicle membrane
ER to Golgi transport vesicle membrane
external side of plasma membrane
extracellular exosome
Golgi membrane
integral component of lumenal side of endoplasmic reticulum membrane
late endosome membrane
lysosomal membrane
MHC class II protein complex
plasma membrane
trans-Golgi network membrane
transport vesicle membrane
MHC class II protein complex binding
peptide antigen binding
virus receptor activity
antigen processing and presentation of exogenous peptide antigen via MHC class II
cytokine-mediated signaling pathway
detection of bacterium
humoral immune response mediated by circulating immunoglobulin
immune response
immunoglobulin production involved in immunoglobulin mediated immune response
inflammatory response to antigenic stimulus
interferon-gamma-mediated signaling pathway
negative regulation of interferon-gamma production
negative regulation of T cell proliferation
positive regulation of insulin secretion involved in cellular response to glucose stimulus
protein tetramerization
regulation of interleukin-10 secretion
regulation of interleukin-4 production
T cell costimulation
T cell receptor signaling pathway
T-helper 1 type immune response - Gene Ontology Biological Process:
- antigen processing and presentation of exogenous peptide antigen via MHC class II
cytokine-mediated signaling pathway
detection of bacterium
humoral immune response mediated by circulating immunoglobulin
immune response
immunoglobulin production involved in immunoglobulin mediated immune response
inflammatory response to antigenic stimulus
interferon-gamma-mediated signaling pathway
negative regulation of interferon-gamma production
negative regulation of T cell proliferation
positive regulation of insulin secretion involved in cellular response to glucose stimulus
protein tetramerization
regulation of interleukin-10 secretion
regulation of interleukin-4 production
T cell costimulation
T cell receptor signaling pathway
T-helper 1 type immune response - Gene Ontology Molecular Function:
- MHC class II protein complex binding
peptide antigen binding
virus receptor activity - Gene Ontology Cellular Component:
- clathrin-coated endocytic vesicle membrane
endocytic vesicle membrane
ER to Golgi transport vesicle membrane
external side of plasma membrane
extracellular exosome
Golgi membrane
integral component of lumenal side of endoplasmic reticulum membrane
late endosome membrane
lysosomal membrane
MHC class II protein complex
plasma membrane
trans-Golgi network membrane
transport vesicle membrane - Keywords:
- 3D-structure
Cell membrane
Complete proteome
Direct protein sequencing
Disulfide bond
Endoplasmic reticulum
Endosome
Glycoprotein
Golgi apparatus
Host cell receptor for virus entry
Host-virus interaction
Immunity
Isopeptide bond
Lysosome
MHC II
Membrane
Polymorphism
Receptor
Reference proteome
Signal
Transmembrane
Transmembrane helix
Ubl conjugation