PTPmu (BK2) Mouse Monoclonal Antibody #4485

Receptor tyrosine phosphatase PTPmu has an extracellular segment characteristic of adhesion molecules: an MEM domain, an Ig domain and four fibronectin III like (FN III) repeats (1,2). PTPmu is proteolytically cleaved into two noncovalently associated fragments: one is the extracellular domain, the other includes the transmembrane and the intracellular catalytic domains. Both fragments are approximately 100 kDa (3). The extracellular domain mediates cell-cell adhesion in a homophilic, Ca2+ independent manner (1,2). PTPmu associates with multiple cadherins (4). It is able to restore E-cadherin-dependent adhesion in human prostate cancer, and is required for N-cadherin-mediated neurite outgrowth (5,6). The phosphatase activity seems to be essential for the latter function but is dispensable for the former (5,6). PTPmu also associates with and recruits a scaffold protein, RACK (receptor for activated protein C kinase), to cell-cell contact sites (7). Both PKCdelta and src seem to be involved in this process (6,7).