Torsin ATPases influence chromatin interaction of the Torsin regulator LAP1
Abstract
The inner nuclear membrane is functionalized by diverse transmembrane proteins that associate with nuclear lamins and/or chromatin. When cells enter mitosis, membrane-chromatin contacts must be broken to allow for proper chromosome segregation; yet how this occurs remains ill-understood. Unexpectedly, we observed that an imbalance in the levels of the lamina-associated polypeptide 1 (LAP1), an activator of ER-resident Torsin AAA+-ATPases, causes a failure in membrane removal from mitotic chromatin, accompanied by chromosome segregation errors and changes in post-mitotic nuclear morphology. These defects are dependent on a hitherto unknown chromatin-binding region of LAP1 that we have delineated. LAP1-induced NE abnormalities are efficiently suppressed by expression of wild-type but not ATPase-deficient Torsins. Furthermore, a dominant-negative Torsin induces chromosome segregation defects in a LAP1-dependent manner. These results indicate that association of LAP1 with chromatin in the nucleus can be modulated by Torsins in the perinuclear space, shedding new light on the LAP1-Torsin interplay.
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All data generated or analysed during this study are included in the manuscript and supporting files.
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Author details
Funding
Swiss National Science Foundation (310030_184801)
- Ulrike Kutay
EPFL
- Beat Fierz
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Megan C King, Yale School of Medicine, United States
Version history
- Received: September 30, 2020
- Accepted: December 15, 2020
- Accepted Manuscript published: December 15, 2020 (version 1)
- Version of Record published: December 30, 2020 (version 2)
Copyright
© 2020, Luithle et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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