Identification of a hormonally regulated protein tyrosine phosphatase associated with bone and testicular differentiation.

摘要: Absence of the tyrosine kinase activity c-src and c-fms results in impairment bone remodeling. Such dysfunction underscores importance phosphorylation, yet role protein phosphatases metabolism remains unexamined. We have isolated cDNA for a novel receptor-like phosphatase expressed testis named osteotesticular (OST-PTP). The deduced 1711-residue possesses an extracellular domain with 10 fibronectin type III repeats cytoplasmic region two catalytic domains. In primary rat osteoblasts, 5.8-kilobase OST-PTP transcript is up-regulated differentiating cultures down-regulated late stage mineralizing cultures. addition, presumed alternate 4.8-5.0 kilobases, which may lack PTP domains, present proliferating but not detectable at other stages. Parathyroid hormone, modulator function, as well cyclic AMP analogues, increase mRNA 5-8-fold UMR 106 cells. situ hybridization adult revealed stage-specific expression OST-PTP. function signaling pathways during remodeling, serve broader cell interactions associated differentiation testis.