Open AccessPhospho-regulation of kinesin-5 during anaphase spindle elongation
Author(s) -
Rachel Avunie-Masala,
Natalia Movshovich,
Yael Nissenkorn,
Adina Gerson-Gurwitz,
Vladimir Fridman,
Mardo Kõivomägi,
Mart Loog,
M. Andrew Hoyt,
Arieh Zaritsky,
Larisa Gheber
Publication year - 2011
Publication title -
journal of cell science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.384
H-Index - 278
eISSN - 1477-9137
pISSN - 0021-9533
DOI - 10.1242/jcs.077396
Subject(s) - microbiology and biotechnology , biology , anaphase , kinesin , spindle pole body , multipolar spindles , spindle apparatus , microtubule , genetics , cell division , cell cycle , cell
The kinesin-5 Saccharomyces cerevisiae homologue Cin8 is shown here to be differentially phosphorylated during late anaphase at Cdk1-specific sites located in its motor domain. Wild-type Cin8 binds to the early-anaphase spindles and detaches from the spindles at late anaphase, whereas the phosphorylation-deficient Cin8-3A mutant protein remains attached to a larger region of the spindle and spindle poles for prolonged periods. This localization of Cin8-3A causes faster spindle elongation and longer anaphase spindles, which have aberrant morphology. By contrast, the phospho-mimic Cin8-3D mutant exhibits reduced binding to the spindles. In the absence of the kinesin-5 homologue Kip1, cells expressing Cin8-3D exhibit spindle assembly defects and are not viable at 37°C as a result of spindle collapse. We propose that dephosphorylation of Cin8 promotes its binding to the spindle microtubules before the onset of anaphase. In mid to late anaphase, phosphorylation of Cin8 causes its detachment from the spindles, which reduces the spindle elongation rate and aids in maintaining spindle morphology.