The role of MEN (mitosis exit network) proteins in the cytokinesis of Saccharomyces cerevisiae.
At the latest stages of their cell cycle, cells carry out crucial processes for the correct segregation of their genetic and cytoplasmic material. In this work, we provide evidence demonstrating that the cell cycle arrest of some MEN (mitosis exit network) mutants in the anaphase-telophase transition is bypassed. In addition, the ability of cdc15 diploid mutant strains to develop non-septated chains of cells, supported by nuclear division, is shown. This phenotype is also displayed by haploid cdc15 mutant strains when cell lysis is prevented by osmotic protection, and shared by other MEN mutants. By contrast, anaphase-telophase arrest is strictly observed in double MEN-FEAR (fourteen early anaphase release) mutants. In this context, the overexpression of a FEAR component, SPO12, in a MEN mutant background enhances the ability of MEN mutants to bypass cell cycle arrest. Taken together, these data suggest a critical role of Cdc15 and other MEN proteins in cytokinesis, allowing a new model for their cellular function to be proposed.
Jimenez
Javier
J
Department of Microbiology and Genetics, Institute of Microbiology and Biochemistry, University of Salamanca/CSIC, Spain. javierj@usal.es
Castelao
Beatriz A
BA
Gonzalez-Novo
Alberto
A
Sanchez-Perez
Miguel
M
D018797:Cell Cycle Proteins / Q000235:genetics / Q000502:physiology*; D048749:Cytokinesis / Q000235:genetics / Q000502:physiology*; D004171:Diploidy; D005656:Fungal Proteins / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000235:genetics / Q000502:physiology*; D006238:Haploidy; D008938:Mitosis / Q000235:genetics / Q000502:physiology*; D009154:Mutation; D009687:Nuclear Proteins; D009997:Osmotic Pressure; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000235:genetics / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000502:physiology*
C082279:CDC15 protein; D018797:Cell Cycle Proteins; D005656:Fungal Proteins; D009687:Nuclear Proteins; C416648:SPO12 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D019204:GTP-Binding Proteins