Abstract
Accurate segregation of chromosomes is critical to ensure that each daughter cell receives the full genetic complement. Maintenance of cohesion between sister chromatids, especially at centromeres, is required to segregate chromosomes precisely during mitosis and meiosis. The Drosophila protein MEI-S332, the founding member of a conserved protein family, is essential in meiosis for maintaining cohesion at centromeres until sister chromatids separate at the metaphase II/anaphase II transition. MEI-S332 localizes onto centromeres in prometaphase of mitosis or meiosis I, remaining until sister chromatids segregate. We elucidated a mechanism for controlling release of MEI-S332 from centromeres via phosphorylation by POLO kinase. We demonstrate that POLO antagonizes MEI-S332 cohesive function and that full POLO activity is needed to remove MEI-S332 from centromeres, yet this delocalization is not required for sister chromatid separation. POLO phosphorylates MEI-S332 in vitro, POLO and MEI-S332 bind each other, and mutation of POLO binding sites prevents MEI-S332 dissociation from centromeres.
Publication types
-
Comparative Study
-
Research Support, Non-U.S. Gov't
-
Research Support, U.S. Gov't, Non-P.H.S.
MeSH terms
-
Animals
-
Binding Sites
-
Blotting, Western / methods
-
Cell Cycle / physiology
-
Cell Cycle Proteins / genetics
-
Cell Cycle Proteins / metabolism*
-
Cells, Cultured
-
Centromere / metabolism*
-
Cyclin B / metabolism
-
Drosophila
-
Drosophila Proteins / genetics
-
Drosophila Proteins / metabolism*
-
Drosophila Proteins / physiology*
-
Electrophoretic Mobility Shift Assay / methods
-
Embryo, Nonmammalian
-
Female
-
Fluorescent Antibody Technique / methods
-
Green Fluorescent Proteins / metabolism
-
Histones / metabolism
-
Immunoprecipitation / methods
-
Indoles / metabolism
-
Larva
-
Male
-
Meiosis / physiology
-
Microscopy, Confocal / methods
-
Mitosis / physiology
-
Models, Biological
-
Mutagenesis / physiology
-
Phosphorylation
-
Protein Serine-Threonine Kinases / physiology*
-
Spermatocytes / metabolism
-
Testis / metabolism
-
Xenopus / metabolism
Substances
-
Cell Cycle Proteins
-
CycB protein, Drosophila
-
Cyclin B
-
Drosophila Proteins
-
Histones
-
Indoles
-
mei-S332 protein, Drosophila
-
Green Fluorescent Proteins
-
DAPI
-
polo protein, Drosophila
-
Protein Serine-Threonine Kinases