| First Author | Molz L | Year | 1996 |
| Journal | J Biol Chem | Volume | 271 |
| Issue | 23 | Pages | 13892-9 |
| PubMed ID | 8662856 | Mgi Jnum | J:33383 |
| Mgi Id | MGI:80864 | Doi | 10.1074/jbc.271.23.13892 |
| Citation | Molz L, et al. (1996) Cpk is a novel class of Drosophila PtdIns 3-kinase containing a C2 domain. J Biol Chem 271(23):13892-9 |
| abstractText | We report the identification of a novel class of phosphatidylinositol (PtdIns) 3-kinases whose members contain C-terminal C2 domains. We have isolated Drosophila and murine genes (termed cpk and cpk-m respectively) by polymerase chain reaction amplification of cDNA libraries with degenerate primers corresponding to conserved regions of PtdIns kinases. The amino acid sequences of Cpk and Cpk-m are most similar to that of p110, a family of PtdIns 3-kinases that mediates the responses of cells to mitogenic stimuli. The Cpk and Cpk-m sequences are similar to a large, central region of p110, but differ from p110 at their N and C termini. The N termini of the Cpk proteins do not contain any recognizable protein motif, while the C termini contain C2 domains, a feature unique among PtdIns kinases. Cpk has an intrinsic PtdIns kinase activity and can phosphorylate PtdIns and PtdIns-4-P, but not PtdIns(4,5)P2, at the D3 position of the inositol ring. Cpk is the first PtdIns 3-kinase identified with this particular substrate specificity. We have identified two potential Cpk-binding proteins, p90 and p190, and have determined that both Cpk and p190 may be tyrosine phosphorylated. This finding suggests that Cpk function may be regulated by tyrosine kinases. |
