Regulation of centromere localization of the Drosophila Shugoshin MEI-S332 and sister-chromatid cohesion in meiosis.
Bottom Line: These studies also suggested that MEI-S332 can be inactivated independently of delocalization, a conclusion supported here by localization and function studies in meiosis.Phosphoresistant and phosphomimetic mutants for the Aurora B and Polo phosphorylation sites were examined for effects on MEI-S332 localization and chromosome segregation in meiosis.Strikingly, MEI-S332 with a phosphomimetic mutation in the Aurora B phosphorylation site prematurely dissociates from the centromeres in meiosis I.
Affiliation: Whitehead Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142.Show MeSH
Related in: MedlinePlus
Mentions: To test the localization properties and function of the T331-A mutant in meiosis, we produced transgenic lines in which this form of MEI-S332-GFP was expressed from the endogenous promoter at levels comparable to wild type (Figure S2). This protein was localized in spermatocytes lacking wild-type MEI-S332. The results contrasted with those obtained in cell culture in that the protein was delocalized from centromeres at the metaphase II/anaphase II transition (Figure 4). Nondisjunction assays were used to quantify the function of MEI-S332T331-A in chromosome segregation. This mutant protein also restored sister-chromatid segregation to mei-S332 mutants (Table 2).
Affiliation: Whitehead Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142.