You can manage bookmarks using lists, please log in to your user account for this.
Media type:
E-Article
Title:
Microtubule binding of the human augmin complex is directly controlled by importins and Ran-GTP
Contributor:
Ustinova, Kseniya;
Ruhnow, Felix;
Gili, Maria;
Surrey, Thomas
imprint:
The Company of Biologists, 2023
Published in:Journal of Cell Science
Language:
English
DOI:
10.1242/jcs.261096
ISSN:
1477-9137;
0021-9533
Origination:
Footnote:
Description:
<jats:title>ABSTRACT</jats:title>
<jats:p>Mitotic spindle assembly during cell division is a highly regulated process. Ran-GTP produced around chromosomes controls the activity of a multitude of spindle assembly factors by releasing them from inhibitory interaction with importins. A major consequence of Ran-GTP regulation is the local stimulation of branched microtubule nucleation around chromosomes, which is mediated by the augmin complex (composed of the eight subunits HAUS1-HAUS8), a process that is crucially important for correct spindle assembly. However, augmin is not known to be a direct target of the Ran-GTP pathway, raising the question of how its activity is controlled. Here, we present the in vitro reconstitution of Ran-GTP-regulated microtubule binding of the human augmin complex. We demonstrate that importins directly bind to augmin, which prevents augmin from binding to microtubules. Ran-GTP relieves this inhibition. Therefore, the augmin complex is a direct target of the Ran-GTP pathway, suggesting that branching microtubule nucleation is directly regulated by the Ran-GTP gradient around chromosomes in dividing cells.</jats:p>