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Nucleocytoplasmic transport in the midzone membrane domain controls yeast mitotic spindle disassembly.

ABSTRACT: During each cell cycle, the mitotic spindle is efficiently assembled to achieve chromosome segregation and then rapidly disassembled as cells enter cytokinesis. Although much has been learned about assembly, how spindles disassemble at the end of mitosis remains unclear. Here we demonstrate that nucleocytoplasmic transport at the membrane domain surrounding the mitotic spindle midzone, here named the midzone membrane domain (MMD), is essential for spindle disassembly in Schizosaccharomyces pombe cells. We show that, during anaphase B, Imp1-mediated transport of the AAA-ATPase Cdc48 protein at the MMD allows this disassembly factor to localize at the spindle midzone, thereby promoting spindle midzone dissolution. Our findings illustrate how a separate membrane compartment supports spindle disassembly in the closed mitosis of fission yeast.

SUBMITTER: Lucena R

PROVIDER: S-EPMC4427787 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Nucleocytoplasmic transport in the midzone membrane domain controls yeast mitotic spindle disassembly.

Lucena Rafael R Dephoure Noah N Gygi Steve P SP Kellogg Douglas R DR Tallada Victor A VA Daga Rafael R RR Jimenez Juan J

The Journal of cell biology 20150501 3

During each cell cycle, the mitotic spindle is efficiently assembled to achieve chromosome segregation and then rapidly disassembled as cells enter cytokinesis. Although much has been learned about assembly, how spindles disassemble at the end of mitosis remains unclear. Here we demonstrate that nucleocytoplasmic transport at the membrane domain surrounding the mitotic spindle midzone, here named the midzone membrane domain (MMD), is essential for spindle disassembly in Schizosaccharomyces pombe ...[more]

PMID: 25963819

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