The Distribution and Characterization of Shps-1, That Binds Protein Tyrosine Phosphatase Shp-2, in the Human and Rat Brain

SHPS-1 is a receptor-like glycoprotein that is tyrosine-phosphorylated and binds SHP-2, a Src homology 2 domain-containing protein tyrosine phosphatase, in response to various mitogens and cell adhesion. SHPS-1 is highly enriched in the brain with its molecular size of similar to 90 kDa. In contrast, it is also expressed in various other organs with its molecular size of 110 to 130 kDa, suggesting that the extents of glycosilation of SHPS-1 may be different among various tissues. Immunohistochemistry of human brain sections revealed that the most intense expression of SHPS-1 was observed in the neurons of hippocampus, inferior olive and putamen. High levels of SHPS-1 were also detected in cortical neurons and cerebellar Purkinje cells. In contrast, a weak or trace signals were observed in glia cells or white matter. Finally, the expression of SHPS-1 correlated with retinoic acid-induced neural differentiation of P19 cells. These results suggest that SHPS-1 may play important roles in a variety of neuronal cells.