This invention provides compositions, organisms and methodologies employing a novel human protein kinase, HPK3P23. The novel human kinase has sequence homology to the catalytic domains of several protein kinases. The gene encoding this novel protein kinase is localized in or near the 3p23 locus of the human chromosome 3. The sequence similarity between the novel human protein and the catalytic domain of protein kinases indicates that the novel human protein may function as a protein kinase.