InterProInterPro Protein Domain record

MHC class I-like antigen recognition
http://metadb.riken.jp/db/SciNetS_rib124i/crib124s1rib124u11161i

MHC class I-like antigen recognition

InterPro Protein Domain record

description
  • <p>Major Histocompatibility Complex (MHC) glycoproteins are heterodimeric cell surface receptors that function to present antigen peptide fragments to T cells responsible for cell-mediated immune responses. MHC molecules can be subdivided into two groups on the basis of structure and function: class I molecules present intracellular antigen peptide fragments (~10 amino acids) on the surface of the host cells to cytotoxic T cells; class II molecules present exogenously derived antigenic peptides (~15 amino acids) to helper T cells. MHC class I and II molecules are assembled and loaded with their peptide ligands via different mechanisms. However, both present peptide fragments rather than entire proteins to T cells, and are required to mount an immune response.</p><p>Class I MHC glycoproteins are expressed on the surface of all somatic nucleated cells, with the exception of neurons. MHC class I receptors present peptide antigens that are synthesised in the cytoplasm, which includes self-peptides (presented for self-tolerance) as well as foreign peptides (such as viral proteins). These antigens are generated from degraded protein fragments that are transported to the endoplasmic reticulum by TAP proteins (transporter of antigenic peptides), where they can bind MHC I molecules, before being transported to the cell surface via the Golgi apparatus [<cite idref="PUB00007109"/>, <cite idref="PUB00016272"/>]. MHC class I receptors display antigens for recognition by cytotoxic T cells, which have the ability to destroy viral-infected or malignant (surfeit of self-peptides) cells.</p><p>MHC class I molecules are comprised of two chains: a MHC alpha chain (heavy chain), and a beta2-microglobulin chain (light chain), where only the alpha chain spans the membrane. The alpha chain has three extracellular domains (alpha 1-3, with alpha1 being at the N terminus), a transmembrane region and a C-terminal cytoplasmic tail. The soluble extracellular beta-2 microglobulin chain associates primarily with the alpha-3 domain and is necessary for MHC stability. The alpha1 and alpha2 domains of the alpha chain are referred to as the recognition region, because the peptide antigen binds in a deep groove between these two domains. </p><p>This entry represents MHC antigen-recognition-like domains from:</p><ul><li>MHC class I, alpha-1 and alpha-2 domains [<cite idref="PUB00035588"/>]</li><li>MHC class I homologue gammadelta T-cell ligand [<cite idref="PUB00035589"/>]</li><li>MHC class I related Ulbp3 [<cite idref="PUB00035590"/>]</li><li>MHC class I related Fc (IgG) receptor, alpha-1 and alpha-2 domains [<cite idref="PUB00025007"/>]</li><li>MHC class I related CD1, alpha-1 and alpha-2 domains [<cite idref="PUB00035591"/>]</li><li>MHC class I related zinc-alpha-2-glycoprotein ZAG (fat depleting factor) [<cite idref="PUB00035592"/>]</li><li>Immunomodulatory protein m144, alpha-1 and alpha-2 domains [<cite idref="PUB00035593"/>]</li><li>Haemochromatosis protein Hfe, alpha-1 and alpha-2 domains [<cite idref="PUB00035594"/>]</li><li>NK cell ligand RAE-1 beta [<cite idref="PUB00035595"/>]</li><li>Endothelial protein C receptor (phospholipid-binding protein) [<cite idref="PUB00035596"/>]</li></ul><p>More information about these proteins can be found at Protein of the Month: MHC [<cite idref="PUB00035862"/>].</p>
label
  • MHC class I-like antigen recognition
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InterPro Protein Domain record
InterPro Protein Domain record