Genes, Vol. 14, Pages 398: Suppressors of Break-Induced Replication in Human Cells

Genes, Vol. 14, Pages 398: Suppressors of Break-Induced Replication in Human Cells Genes doi: 10.3390/genes14020398 Authors: Stanley Dean Rider French J. Damewood Rujuta Yashodhan Gadgil David C. Hitch Venicia Alhawach Resha Shrestha Matilyn Shanahan Nathen Zavada Michael Leffak Short tandem DNA repeats are drivers of genome instability. To identify suppressors of break-induced mutagenesis human cells, unbiased genetic screens were conducted using a lentiviral shRNA library. The recipient cells possessed fragile non-B DNA that could induce DNA double-strand breaks (DSBs), integrated at an ectopic chromosomal site adjacent to a thymidine kinase marker gene. Mutagenesis of the thymidine kinase gene rendered cells resistant to the nucleoside analog ganciclovir (GCV). The screen identified genes that have established roles in DNA replication and repair, chromatin modification, responses to ionizing radiation, and genes encoding proteins enriched at replication forks. Novel loci implicated in BIR included olfactory receptors, the G0S2 oncogene/tumor suppressor axis, the EIF3H-METTL3 translational regulator, and the SUDS3 subunit of the Sin3A corepressor. Consistent with a role in suppressing BIR, siRNA knockdown of selected candidates increased the frequency of the GCVr phenotype and increased DNA rearrangements near the ectopic non-B DNA. Inverse PCR and DNA sequence analyses showed that hits identified in the screen increased genome instability. Further a...
Source: Genes - Category: Genetics & Stem Cells Authors: Tags: Article Source Type: research