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bioRxiv · 10.1101/536045

DnaJB6 is a RanGTPdependent microtubule Organization during mitosis

Rosas-Salvans, M.·Vernos, I.
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Abstract

Bipolar spindle organization is essential for the faithful segregation of chromosomes during cell division. This organization relies on the collective activities of motor proteins. The minus-end directed dynein motor complex generates spindle inward forces and plays a major role in spindle pole focusing. The dynactin complex regulates many dynein functions increasing its processivity and force production. Here we show that DnaJB6 is a novel RanGTP regulated protein. It interacts with dynactin p150Glued in a RanGTP-dependent manner specifically in M-phase and promotes spindle pole focusing and dynein force generation. Our data suggest a novel mechanism by which RanGTP regulates dynein activity during M-phase. Summary statementWe describe DnaJB6 as a novel RanGTP-regulated protein important for spindle assembly. Our data suggest that RanGTP regulates dynein-dependent inward spindle force generation and pole focusing through DnaJB6

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Rosas-Salvans, M., Vernos, I.. 2019-01-31. DnaJB6 is a RanGTPdependent microtubule Organization during mitosis. https://doi.org/10.1101/536045

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