Nuclear F-actin counteracts nuclear deformation and promotes fork repair during replication stress

Autor:	Noa, Lamm, Mark N, Read, Max, Nobis, David, Van Ly, Scott G, Page, V Pragathi, Masamsetti, Paul, Timpson, Maté, Biro, Anthony J, Cesare
Rok vydání:	2020
Předmět:	Cell Nucleus DNA Replication Mice Knockout DNA Repair Antineoplastic Agents Mice SCID Mechanistic Target of Rapamycin Complex 1 Xenograft Model Antitumor Assays Actins Carboplatin Cell Line Polymerization Actin Cytoskeleton Mice Inbred NOD Cell Line Tumor Neoplasms Animals Humans
Zdroj:	Nature cell biology. 22(12)
ISSN:	1476-4679
Popis:	Filamentous actin (F-actin) provides cells with mechanical support and promotes the mobility of intracellular structures. Although F-actin is traditionally considered to be cytoplasmic, here we reveal that nuclear F-actin participates in the replication stress response. Using live and super-resolution imaging, we find that nuclear F-actin is polymerized in response to replication stress through a pathway regulated by ATR-dependent activation of mTORC1, and nucleation through IQGAP1, WASP and ARP2/3. During replication stress, nuclear F-actin increases the nuclear volume and sphericity to counteract nuclear deformation. Furthermore, F-actin and myosin II promote the mobility of stressed-replication foci to the nuclear periphery through increasingly diffusive motion and directed movements along the nuclear actin filaments. These actin functions promote replication stress repair and suppress chromosome and mitotic abnormalities. Moreover, we find that nuclear F-actin is polymerized in vivo in xenograft tumours after treatment with replication-stress-inducing chemotherapeutic agents, indicating that this pathway has a role in human disease.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=pmid________::45682de39a9b02505fd17d1cbbceac78 https://pubmed.ncbi.nlm.nih.gov/33257806 Zobrazit plný text záznamu Full text from SpringerLink