Premium
Src family kinase phosphorylation of the motor domain of the human kinesin‐5, Eg5
Author(s) -
Bickel Kathleen G.,
Mann Barbara J.,
Waitzman Joshua S.,
Poor Taylor A.,
Rice Sarah E.,
Wadsworth Patricia
Publication year - 2017
Publication title -
cytoskeleton
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.95
H-Index - 86
eISSN - 1949-3592
pISSN - 1949-3584
DOI - 10.1002/cm.21380
Subject(s) - kinesin , biology , microbiology and biotechnology , phosphorylation , mitosis , kinase , motor protein , mutant , spindle apparatus , molecular motor , microtubule , biochemistry , cell division , gene , cell
Spindle formation in mammalian cells requires precise spatial and temporal regulation of the kinesin‐5, Eg5, which generates outward force to establish spindle bipolarity. Our results demonstrate that Eg5 is phosphorylated in cultured cells by Src family kinases (SFKs) at three sites in the motor head: Y125, Y211, and Y231. Mutation of these sites diminishes motor activity in vitro , and replacement of endogenous Eg5 with phosphomimetic Y211 in LLC‐Pk1 cells results in monopolar spindles, consistent with loss of Eg5 activity. Cells treated with SFK inhibitors show defects in spindle formation, similar to those in cells expressing the nonphosphorylatable Y211 mutant, and distinct from inhibition of other mitotic kinases. We propose that this phosphoregulatory mechanism tunes Eg5 enzymatic activity for optimal spindle morphology.