Mitotic motors and chromosome segregation: The mechanism of anaphase B

Ingrid Brust-Mascher, Jonathan M. Scholey

Research output: Contribution to journalArticle

20 Scopus citations

Abstract

Anaphase B spindle elongation plays an important role in chromosome segregation. In the present paper, we discuss our model for anaphase B in Drosophila syncytial embryos, in which spindle elongation depends on an ip (interpolar) MT (microtubule) sliding filament mechanism generated by homotetrameric kinesin-5 motors acting in concert with poleward ipMT flux, which acts as an 'on/off' switch. Specifically, the preanaphase B spindle is maintained at a steady-state length by the balance between ipMT sliding and ipMT depolymerization at spindle poles, producing poleward flux. Cyclin B degradation at anaphase B onset triggers: (i) an MT catastrophe gradient causing ipMT plus ends to invade the overlap zone where ipMT sliding forces are generated; and (ii) the inhibition of ipMT minus-end depolymerization so flux is turned 'off', tipping the balance of forces to allow outward ipMT sliding to push apart the spindle poles. We briefly comment on the relationship of this model to anaphase B in other systems.

Original languageEnglish (US)
Pages (from-to)1149-1153
Number of pages5
JournalBiochemical Society Transactions
Volume39
Issue number5
DOIs
StatePublished - Oct 2011

Keywords

  • Anaphase B
  • Mitotic motor
  • Poleward flux
  • Spindle elongation

ASJC Scopus subject areas

  • Biochemistry

Fingerprint Dive into the research topics of 'Mitotic motors and chromosome segregation: The mechanism of anaphase B'. Together they form a unique fingerprint.

  • Cite this