The intrinsic polarity of microtubules within cells is exploited each time cells divide, Kinesins, microtubule-associated motor proteins, are required to execute the dramatic events of mitosis: bipolar spindle assembly, metaphase chromosome alignment, anaphase chromosome segregation, and separation of spindle poles prior to cytokinesis. Surprisingly kinesin-related proteins have been found to move in either "plus-ward" or "minus-ward" directions along microtubules. Evidence from genetic analyses of simple eukaryotes and in vitro activity assays supports the notion that certain subfamilies of kinesin-related proteins provide antagonistic activities necessary to balance mitotic forces. A recent study by Sharp et al.((1)), sheds further light on the subject by exploiting the genetics and cytology of the fruit fly embryo. BioEssays 21:985-990, 1999. (C) 1999 John Wiley & Sons, Inc.
|Number of pages||6|
|Publication status||Published - Dec 1999|