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 useful to understand the molecular mechanisms that underlie proliferation and differentiation in cells found in this compartment. We used the polymerase chain reaction (PCR) to amplify the catalytic kinase domain of serine-threonine kinases by employing degenerate primers and then screened an intestinal crypt cDNA library to clone and sequence the open reading frame of a novel serine-threonine kinase. This was then further characterized by Northern blot analysis and RNA in situ hybridization. This kinase, designated intestinal cell kinase, harbors a dual phosphorylation site found in mitogen-activating protein (MAP) kinases that is important for kinase activity.