Chromator, a novel and essential chromodomain protein interacts directly with the putative spindle matrix protein skeletor.
We have used a yeast two-hybrid interaction assay to identify Chromator, a novel chromodomain containing protein that interacts directly with the putative spindle matrix protein Skeletor. Immunocytochemistry demonstrated that Chromator and Skeletor show extensive co-localization throughout the cell cycle. During interphase Chromator is localized on chromosomes to interband chromatin regions in a pattern that overlaps that of Skeletor. However, during mitosis both Chromator and Skeletor detach from the chromosomes and align together in a spindle-like structure. Deletion construct analysis in S2 cells showed that the COOH-terminal half of Chromator without the chromodomain was sufficient for both nuclear as well as spindle localization. Analysis of P-element mutations in the Chromator locus shows that Chromator is an essential protein. Furthermore, RNAi depletion of Chromator in S2 cells leads to abnormal microtubule spindle morphology and to chromosome segregation defects. These findings suggest that Chromator is a nuclear protein that plays a role in proper spindle dynamics during mitosis.
Rath
Uttama
U
Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA.
Wang
Dong
D
Ding
Yun
Y
Xu
Ying-Zhi
YZ
Qi
Hongying
H
Blacketer
Melissa J
MJ
Girton
Jack
J
Johansen
Jørgen
J
Johansen
Kristen M
KM
D000595:Amino Acid Sequence; D000818:Animals; D002453:Cell Cycle / Q000502:physiology; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D034521:Nuclear Matrix-Associated Proteins / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D034622:RNA Interference; D008941:Spindle Apparatus / Q000378:metabolism*; D020798:Two-Hybrid System Techniques
C498868:Chro protein, Drosophila; D002868:Chromosomal Proteins, Non-Histone; D029721:Drosophila Proteins; D034521:Nuclear Matrix-Associated Proteins; C419556:skeletor protein, Drosophila