A conserved mitotic kinase active at late anaphase-telophase in syncytial Drosophila embryos.
Mutations in the Drosophila gene polo cause abnormal mitotic and meiotic divisions. This gene encodes a 577-amino-acid protein that has an N-terminal putative kinase domain and a 300-residue C-terminal domain. In budding yeast, a homologous kinase is encoded by CDC5 (ref. 3), a gene required for nuclear division late in the mitotic cycle and during meiosis. Murine homologues have also been described. Here we show that the polo gene product immunoprecipitated from extracts of single Drosophila embryos can phosphorylate casein in vitro, and that the kinase activity peaks cyclically at late anaphase/telophase. This contrasts with the cyclical activity of cyclin B-associated p34cdc2 kinase, which is maximal upon entry into mitosis during the rapid cycles of mitosis in the syncytium.
Department of Anatomy and Physiology, University of Dundee, UK.
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Fenton
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Glover
D000705:Anaphase; D000818:Animals; D016203:CDC2 Protein Kinase / Q000378:metabolism; D002364:Caseins / Q000378:metabolism; D002459:Cell Fusion; D016213:Cyclins / Q000378:metabolism; D004330:Drosophila / Q000196:embryology / Q000201:enzymology*; D029721:Drosophila Proteins; D007814:Larva / Q000201:enzymology; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D013692:Telophase
D002364:Caseins; D016213:Cyclins; D029721:Drosophila Proteins; C072004:polo protein, Drosophila; D017346:Protein Serine-Threonine Kinases; D016203:CDC2 Protein Kinase