Cell surface receptor, which is involved in signal transduction processes. Recruits PTPN11/SHP-2 to the cell membrane and is a putative substrate of PTPN11/SHP-2. Is a major receptor for concanavalin-A (ConA) and is involved in cellular signaling induced by ConA, which probably includes Src family tyrosine-protein kinases. Isoform 3 seems to have a dominant negative role; it blocks tyrosine phosphorylation of MPZL1 induced by ConA. Isoform 1, but not isoform 2 and isoform 3, may be involved in regulation of integrin-mediated cell motility.
Subcellular locations: Membrane
Widely expressed with highest levels in heart, placenta, kidney and pancreas. Isoform 3 is relatively abundant in hematopoietic tissues and fetal liver. Isoform 1 and isoform 3 are expressed in CD14- PB monocytes and pre-B cell progenitors. Isoform 3 appears to be the major isoform in CD34- promyelocytic and promonocytic cells. During differentiation in monocytic cells, the expression level of isoform 3 decreases and that of isoform 1 increases. Isoform 1 is prominent in stromal cells and, to a lesser extent, in umbilical vein endothelial cells and erythroid progenitors. Isoform 2 is expressed in a erythroid progenitor cell line.