Genetic and phenotypic analysis of alleles of the Drosophila chromosomal JIL-1 kinase reveals a functional requirement at multiple developmental stages.
In this study we provide a cytological and genetic characterization of the JIL-1 locus in Drosophila. JIL-1 is an essential chromosomal tandem kinase and in JIL-1 null animals chromatin structure is severely perturbed. Using a range of JIL-1 hypomorphic mutations, we show that they form an allelic series. JIL-1 has a strong maternal effect and JIL-1 activity is required at all stages of development, including embryonic, larval, and pupal stages. Furthermore, we identified a new allele of JIL-1, JIL-1(h9), that encodes a truncated protein missing COOH-terminal sequences. Remarkably, the truncated JIL-1 protein can partially restore viability without rescuing the defects in polytene chromosome organization. This suggests that sequences within this region of JIL-1 play an important role in establishing and/or maintaining normal chromatin structure. By analyzing the effects of JIL-1 mutations we provide evidence that JIL-1 function is necessary for the normal progression of several developmental processes at different developmental stages such as oogenesis and segment specification. We propose that JIL-1 may exert such effects by a general regulation of chromatin structure affecting gene expression.
Zhang
Weiguo
W
Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA.
Jin
Ye
Y
Ji
Yun
Y
Girton
Jack
J
Johansen
Jørgen
J
Johansen
Kristen M
KM
D000483:Alleles; D000818:Animals; D002875:Chromosomes; D004330:Drosophila / Q000235:genetics* / Q000254:growth & development; D005260:Female; D017403:In Situ Hybridization; D010641:Phenotype; D011494:Protein Kinases / Q000235:genetics*
D011494:Protein Kinases