Abstract

Centromeres and pericentromeres are specialized chromatin regions whose organization is critical for proper chromosome segregation through dynamic microtubule attachment. Smc5/6, highly enriched in pericentromeres, associates with microtubules. However, whether Smc5/6 contributes to chromatin folding and dynamics in these regions remains unclear. Here, we dissect Smc5/6 function at budding yeast centromeres by constructing smc5-2KE, a separation-of-function mutant that reduces microtubule binding by replacing two lysines (K624 and K631) at the Smc5 hinge with glutamic acid. After demonstrating reduced microtubule binding by smc5-2KE in vitro, we use high temporal resolution imaging in living cells and polymer modeling to show that Smc5/6 and microtubule binding restricts chromatin dynamics along chromosome arms, thus contributing to pericentromeric chromatin folding. The smc5-2KE mutant shows a strong pericentromere-specific reduction in homologous recombination repair, as well as defects in mitotic spindle length, centromere clustering and cytokinesis. Overall, our results reveal that Smc5/6-microtubule association ensures robust pericentromeric chromatin folding, contributing to genome integrity in the face of mitotic forces.

Competing Interest Statement

The authors have declared no competing interest.

Details

Title
Smc5/6 association with microtubules controls dynamic pericentromeric chromatin folding
Author
Carre-Simon, Annia; Batrin, Renaud; Isler, Sarah; Henrik Dahl Pinholt; Foldes, Timothy; Laflamme, Guillaume; Barbi, Maria; Mirny, Leonid; D'amours, Damien; Fabre, Emmanuelle
University/institution
Cold Spring Harbor Laboratory Press
Section
New Results
Publication year
2024
Publication date
Nov 15, 2024
Publisher
Cold Spring Harbor Laboratory Press
ISSN
2692-8205
Source type
Working Paper
Language of publication
English
ProQuest document ID
3128875140
Copyright
© 2024. This article is published under http://creativecommons.org/licenses/by-nd/4.0/ (“the License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.