Makenzie S Thomas, Gautham S Pillai, Margaret A Butler, Joel Fernandez, Jeannine R LaRocque
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引用次数: 0
Abstract
Double-strand breaks (DSBs) are genotoxic DNA lesions that pose significant threats to genomic stability, necessitating precise and efficient repair mechanisms to prevent cell death or mutations. DSBs are repaired through nonhomologous end-joining (NHEJ) or homology-directed repair (HDR), which includes homologous recombination (HR) and single-strand annealing (SSA). CtIP and Rif1 are conserved proteins implicated in DSB repair pathway choice, possibly through redundant roles in promoting DNA end-resection required for HDR. Although the roles of these proteins have been well-established in other organisms, the role of Rif1 and its potential redundancies with CtIP in Drosophila melanogaster remain elusive. To examine the roles of DmCtIP and DmRif1 in DSB repair, this study employed the direct repeat of white (DR-white) assay, tracking across indels by decomposition (TIDE) analysis, and P{wIw_2 kb 3'} assay to track repair outcomes in HR, NHEJ, and SSA, respectively. These experiments were performed in DmCtIPΔ/Δ single mutants, DmRif1Δ/Δ single mutants, and DmRif1Δ/Δ; DmCtIPΔ/Δ double mutants. This work demonstrates significant defects in both HR and SSA repair in DmCtIPΔ/Δ and DmRif1Δ/Δ single mutants. However, experiments in DmRif1Δ/Δ; DmCtIPΔ/Δ double mutants reveal that DmCtIP is epistatic to DmRif1 in promoting HDR. Overall, this study concludes that DmRif1 and DmCtIP do not perform their activities in a redundant pathway, but rather DmCtIP is the main driver in promoting HR and SSA, most likely through its role in end resection.
期刊介绍:
G3: Genes, Genomes, Genetics provides a forum for the publication of high‐quality foundational research, particularly research that generates useful genetic and genomic information such as genome maps, single gene studies, genome‐wide association and QTL studies, as well as genome reports, mutant screens, and advances in methods and technology. The Editorial Board of G3 believes that rapid dissemination of these data is the necessary foundation for analysis that leads to mechanistic insights.
G3, published by the Genetics Society of America, meets the critical and growing need of the genetics community for rapid review and publication of important results in all areas of genetics. G3 offers the opportunity to publish the puzzling finding or to present unpublished results that may not have been submitted for review and publication due to a perceived lack of a potential high-impact finding. G3 has earned the DOAJ Seal, which is a mark of certification for open access journals, awarded by DOAJ to journals that achieve a high level of openness, adhere to Best Practice and high publishing standards.