EPOR Antikörper

Erythropoietin (EPO) is the major glycoprotein hormone regulator of mammalian erythropoiesis, and is produced by kidney and liver in an oxygen-dependent manner. The biological effects of EPO are mediated by the specific erythropoietin receptor (EPOR) on bone marrow erythroblasts, which transmits signals important for both proliferation and differentiation along the erythroid lineage. EPOR is a type 1 single-transmembrane cytokine receptor, and belongs to the homodimerizing subclass which functions as ligand-induced or ligand-stabilized homodimers. Mouse EPOR contains a tryptophan-serine-X-tryptophan-serine (WSXWS) motif and 1 copy of a cytoplasmic immunoreceptor tyrosine-based inhibitor motif (ITIM) motif, and shares approximately 80% amino acid sequence identity with the human EPOR. Mouse EPOR is expressed in relatively mature erythroid progenitor cells and in EPO-responsive erythroleukemia cells. EPO binding to EPOR triggers auto- or trans-phosphorylation of a protein-tyrosine kinase JAK2 bound to the receptor cytosolic (CT) domain, and subsequently JAK2 activates a variety of intracellular signal substrates including Ras/MAPK, phosphatidylinositol 3-kinase and STAT transcription factors. The stimulated EPOR appears to function in erythroid cell survival through preventing the PCD, and is also suggested to play a neuroprotective role for its expression in mammalian brains.

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