Intestinal cell kinase (ICK) localizes to the crypt region and requires a dual phosphorylation site found in map kinases

Identification of key regulatory kinases in the intestinal epithelium are u seful to understand the molecular mechanisms that underlie proliferation an d differentiation in cells found in this compartment. We used the polymeras e chain reaction (PCR) to amplify the catalytic kinase domain of serine-thr eonine kinases by employing degenerate primers and then screened an intesti nal crypt cDNA library to clone and sequence the open reading frame of a no vel serine-threonine kinase. This was then further characterized by Norther n blot analysis and RNA in situ hybridization. This kinase, designated inte stinal cell kinase, harbors a dual phosphorylation site found in mitogen-ac tivating protein (MAP) kinases that is important for kinase activity. (C) 2 000 Wiley-Liss, Inc.