Artículo
Actin nucleators safeguard replication forks by limiting nascent strand degradation
Autor/es | Nieminuszczy, J.
Martin, P. R. Broderick, R. Krwawicz, J. Kanellou, A. Mocanu, C. Bousgouni, V. Smith, C. Aguilera López, Andrés Niedzwiedz, Wojciech |
Departamento | Universidad de Sevilla. Departamento de Genética |
Fecha de publicación | 2023 |
Fecha de depósito | 2023-07-21 |
Publicado en |
|
Resumen | Accurate genome replication is essential for all life and a key mechanism of disease prevention, underpinned by the ability of cells to respond to replicative stress (RS) and protect replication forks. These responses rely ... Accurate genome replication is essential for all life and a key mechanism of disease prevention, underpinned by the ability of cells to respond to replicative stress (RS) and protect replication forks. These responses rely on the formation of Replication Protein A (RPA)-single stranded (ss) DNA complexes, yet this process remains largely uncharacterized. Here, we establish that actin nucleation-promoting factors (NPFs) associate with replication forks, promote efficient DNA replication and facilitate association of RPA with ssDNA at sites of RS. Accordingly, their loss leads to deprotection of ssDNA at perturbed forks, impaired ATR activation, global replication defects and fork collapse. Supplying an excess of RPA restores RPA foci formation and fork protection, suggesting a chaperoning role for actin nucleators (ANs) (i.e. Arp2/3, DIAPH1) and NPFs (i.e, WASp, N-WASp) in regulating RPA availability upon RS. We also discover that β-actin interacts with RPA directly in vitro, and in vivo a hyper-depolymerizing β-actin mutant displays a heightened association with RPA and the same dysfunctional replication phenotypes as loss of ANs/NPFs, which contrasts with the phenotype of a hyper-polymerizing β-actin mutant. Thus, we identify components of actin polymerization pathways that are essential for preventing ectopic nucleolytic degradation of perturbed forks by modulating RPA activity. |
Agencias financiadoras | Cancer Reserch. United Kingdom National Institutes of Health. United States European Research Council (ERC) |
Identificador del proyecto | C17183/A23303
R01AI146380 ERC2014 AdG669898 TARLOOP |
Cita | Nieminuszczy, J., Martin, P.R., Broderick, R., Krwawicz, J., Kanellou, A., Mocanu, C.,...,Niedzwiedz, W. (2023). Actin nucleators safeguard replication forks by limiting nascent strand degradation. Nucleic Acids Research, 51 (12), 6337-6354. https://doi.org/10.1093/nar/gkad369. |
Ficheros | Tamaño | Formato | Ver | Descripción |
---|---|---|---|---|
Actin nucleators.pdf | 2.026Mb | [PDF] | Ver/ | |