PDGFR-beta Antibody – Rat Monoclonal

Function: Tyrosine-protein kinase that acts as cell-surface receptor for homodimeric PDGFB and PDGFD and for heterodimers formed by PDGFA and PDGFB, and plays an essential role in the regulation of embryonic development, cell proliferation, survival, differentiation, chemotaxis and migration. Plays an essential role in blood vessel development by promoting proliferation, migration and recruitment of pericytes and smooth muscle cells to endothelial cells. Plays a role in the migration of vascular smooth muscle cells and the formation of neointima at vascular injury sites. Required for normal development of the cardiovascular system. Required for normal recruitment of pericytes (mesangial cells) in the kidney glomerulus, and for normal formation of a branched network of capillaries in kidney glomeruli. Promotes rearrangement of the actin cytoskeleton and the formation of membrane ruffles. Binding of its cognate ligands - homodimeric PDGFB, heterodimers formed by PDGFA and PDGFB or homodimeric PDGFD -leads to the activation of several signaling cascades; the response depends on the nature of the bound ligand and is modulated by the formation of heterodimers between PDGFRA and PDGFRB. Phosphorylates PLCG1, PIK3R1, PTPN11, RASA1/GAP, CBL, SHC1 and NCK1. Activation of PLCG1 leads to the production of the cellular signaling molecules diacylglycerol and inositol 1,4,5-trisphosphate, mobilization of cytosolic Ca2+ and the activation of protein kinase C. Phosphorylation of PIK3R1, the regulatory subunit of phosphatidylinositol 3-kinase, leads to the activation of the AKT1 signaling pathway. Phosphorylation of SHC1, or of the C-terminus of PTPN11, creates a binding site for GRB2, resulting in the activation of HRAS, RAF1 and down-stream MAP kinases, including MAPK1/ERK2 and/or MAPK3/ERK1. Promotes phosphorylation and activation of SRC family kinases. Promotes phosphorylation of PDCD6IP/ALIX and STAM

By similarity. Receptor signaling is down-regulated by protein phosphatases that dephosphorylate the receptor and its down-stream effectors, and by rapid internalization of the activated receptor. Ref.2 Ref.6 Ref.8 Ref.10 Ref.12 Ref.13 Ref.15 Ref.17 Ref.18

Catalytic activity: ATP + a [protein]-L-tyrosine = ADP + a [protein]-L-tyrosine phosphate. Ref.8

Enzyme regulation: Present in an inactive conformation in the absence of bound ligand. Binding of PDGFB and/or PDGFD leads to dimerization and activation by autophosphorylation on tyrosine residues.

Subunit structure: Interacts with homodimeric PDGFB and PDGFD, and with heterodimers formed by PDGFA and PDGFB. May also interact with homodimeric PDGFC. Monomer in the absence of bound ligand. Interaction with homodimeric PDGFB, heterodimers formed by PDGFA and PDGFB or homodimeric PDGFD, leads to receptor dimerization, where both PDGFRA homodimers and heterodimers with PDGFRB are observed. Interacts with SH2B2/APS. Interacts directly (tyrosine phosphorylated) with SHB. Interacts (tyrosine phosphorylated) with PIK3R1. Interacts (tyrosine phosphorylated) with CBL. Interacts (tyrosine phosphorylated) with SRC and SRC family kinases. Interacts (tyrosine phosphorylated) with PIK3C2B, maybe indirectly. Interacts (tyrosine phosphorylated) with SHC1, GRB7, GRB10 and NCK1. Interaction with GRB2 is mediated by SHC1. Interacts (via C-terminus) with SLC9A3R1

By similarity. Ref.2 Ref.4 Ref.8 Ref.11 Ref.12 Ref.17 Ref.19

Subcellular location: Cell membrane; Single-pass type I membrane protein. Cytoplasmic vesicle

By similarity. Lysosome lumen

By similarity. Note: After ligand binding, the autophosphorylated receptor is ubiquitinated and internalized, leading to its degradation.

Tissue specificity: Weakly expressed in glomerular mesangial cells and interstitial cells. Up-regulated in areas of renal fibrosis. In mice with unilateral ureteral obstruction, increased expression in interstitial cells at day 4 and expression is markedly elevated at day 7 and is maximal at day 14. Ref.5

Post-translational modification: Autophosphorylated on tyrosine residues upon ligand binding. Autophosphorylation occurs in trans, i.e. one subunit of the dimeric receptor phosphorylates tyrosine residues on the other subunit. Phosphorylation at Tyr-578, and to a lesser degree, Tyr-580 is important for interaction with SRC. Phosphorylation at Tyr-715 is important for interaction with GRB2. Phosphorylation at Tyr-739 and Tyr-750 is important for interaction with PIK3R1. Phosphorylation at Tyr-750 is important for interaction with NCK1. Phosphorylation at Tyr-770 and Tyr-856 is important for interaction with RASA1/GAP. Phosphorylation at Tyr-856 is important for efficient phosphorylation of PLCG1 and PTPN11, resulting in increased phosphorylation of AKT1, MAPK1/ERK2 and/or MAPK3/ERK1, PDCD6IP/ALIX and STAM, and in increased cell proliferation. Phosphorylation at Tyr-1008 is important for interaction with PTPN11. Phosphorylation at Tyr-1008 and Tyr-1020 is important for interaction with PLCG1. Dephosphorylated by PTPRJ at Tyr-750, Tyr-856, Tyr-1008 and Tyr-1020

By similarity. Dephosphorylated by PTPN2 at Tyr-578 and Tyr-1020. Ref.2 Ref.9 Ref.10N-glycosylated

By similarity.Ubiquitinated. After autophosphorylation, the receptor is polyubiquitinated, leading to its degradation. Ref.11

Disruption phenotype: No apparent phenotype up to 16 dpc. Lethality late during gestation or at birth, due to widespread bleedings. This is due to a severe shortage of vascular smooth muscle cells and pericytes, especially in the central nervous system, skin, lung and heart. Mutants suffer from hemorrhages, anemia, thrombocytopenia, and show defects in the formation of kidney glomeruli, due to a lack of mesangial cells. Ref.3 Ref.7 Ref.14

Sequence similarities: Belongs to the protein kinase superfamily. Tyr protein kinase family. CSF-1/PDGF receptor subfamily.Contains 5 Ig-like C2-type (immunoglobulin-like) domains.Contains 1 protein kinase domain.