title: The COOH-terminal domain of the JIL-1 histone H3S10 kinase interacts with histone H3 and is required for correct targeting to chromatin.
abstract: The JIL-1 histone H3S10 kinase in Drosophila localizes specifically to euchromatic interband regions of polytene chromosomes and is enriched 2-fold on the male X chromosome. JIL-1 can be divided into four main domains including an NH(2)-terminal domain, two separate kinase domains, and a COOH-terminal domain. Our results demonstrate that the COOH-terminal domain of JIL-1 is necessary and sufficient for correct chromosome targeting to autosomes but that both COOH- and NH(2)-terminal sequences are necessary for enrichment on the male X chromosome. We furthermore show that a small 53-amino acid region within the COOH-terminal domain can interact with the tail region of histone H3, suggesting that this interaction is necessary for the correct chromatin targeting of the JIL-1 kinase. Interestingly, our data indicate that the COOH-terminal domain alone is sufficient to rescue JIL-1 null mutant polytene chromosome defects including those of the male X chromosome. Nonetheless, we also found that a truncated JIL-1 protein which was without the COOH-terminal domain but retained histone H3S10 kinase activity was able to rescue autosome as well as partially rescue male X polytene chromosome morphology. Taken together these findings indicate that JIL-1 may participate in regulating chromatin structure by multiple and partially redundant mechanisms.
authors.affiliation: Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA.
authors.forename: Xiaomin
authors.initials: X
authors.lastname: Bao
authors.forename: Weili
authors.initials: W
authors.lastname: Cai
authors.forename: Huai
authors.initials: H
authors.lastname: Deng
authors.forename: Weiguo
authors.initials: W
authors.lastname: Zhang
authors.forename: Robert
authors.initials: R
authors.lastname: Krencik
authors.forename: Jack
authors.initials: J
authors.lastname: Girton
authors.forename: Jørgen
authors.initials: J
authors.lastname: Johansen
authors.forename: Kristen M
authors.initials: KM
authors.lastname: Johansen
mesh_terms: D000818:Animals; D002843:Chromatin / Q000737:chemistry*; D002875:Chromosomes / Q000648:ultrastructure; D029721:Drosophila Proteins / Q000737:chemistry* / Q000378:metabolism; D004331:Drosophila melanogaster; D017353:Gene Deletion; D006657:Histones / Q000737:chemistry*; D008856:Microscopy, Fluorescence; D008954:Models, Biological; D008968:Molecular Conformation; D009154:Mutation; D011485:Protein Binding; D017346:Protein Serine-Threonine Kinases / Q000737:chemistry* / Q000378:metabolism; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000737:chemistry
chemical_list: D002843:Chromatin; D029721:Drosophila Proteins; D006657:Histones; D011993:Recombinant Fusion Proteins; C507306:JIL-1 protein, Drosophila; D017346:Protein Serine-Threonine Kinases