A bipolar kinesin.

A S Kashina; R J Baskin; D G Cole; K P Wedaman; W M Saxton; J M Scholey

doi:10.1038/379270a0

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PubMed · 8538794

A bipolar kinesin.

A S Kashina·R J Baskin·D G Cole·K P Wedaman·W M Saxton·J M Scholey

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Abstract

Chromosome segregation during mitosis depends on the action of the mitotic spindle, a self-organizing, bipolar protein machine which uses microtubules (MTs) and their associated motors. Members of the BimC subfamily of kinesin-related MT-motor proteins are believed to be essential for the formation and functioning of a normal bipolar spindle. Here we report that KRP130, a homotetrameric BimC-related kinesin purified from Drosophila melanogaster embryos, has an unusual ultrastructure. It consists of four kinesin-related polypeptides assembled into a bipolar aggregate with motor domains at opposite ends, analogous to a miniature myosin filament. Such a bipolar 'minifilament' could crosslink spindle MTs and slide them relative to one another. We do not know of any other MT motors that have a bipolar structure.

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Amino Acid Sequence Animals Antibodies Calcium-Binding Proteins Drosophila melanogaster Kinesins Molecular Sequence Data Muscle Proteins Protein Conformation Spindle Apparatus Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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A S Kashina, R J Baskin, D G Cole, K P Wedaman, W M Saxton, J M Scholey. 1996-01-18. A bipolar kinesin.. https://doi.org/10.1038/379270a0

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