Cloning, mapping, and expression of ial, a novel Drosophila member of the Ipl1/aurora mitotic control kinase family

The members of the Ipl1-aurora like kinase (IARK) subfamily are conserved s erine/threonine kinases that play a key role in the control of chromosome s egregation, centrosome separation, and cytokinesis from yeast to mammals. W e report on the isolation of a new Drosophila member of the family, designa ted Ipl1-auroralike kinase (ial) Phylogenetic analysis of kinase domains es tablished that ial is more divergent from known mammalian IARKs than is aur ora. Mapping based on examination of chromosomal aberrations, together with mapping within contigs identified by the Drosophila Genome Project, placed the gene at 32B on the left arm of the second chromosome. Discrete single- gene mutations in this region, including all known relevant P-element disru ptions, were examined and proven not to be mutations in ial. Characterizati on of spatial and temporal expression of ial and its gene product showed th at it manifests itself in patterns which can be consistent with a role in c ell cycle control.