title: Homologous recombination as a mechanism to recognize repetitive DNA sequences in an RNAi pathway.
abstract: Quelling is an RNAi-related phenomenon that post-transcriptionally silences repetitive DNA and transposons in Neurospora. We previously identified a type of DNA damage-induced small RNA called qiRNA that originates from ribosomal DNA. To understand how small RNAs are generated from repetitive DNA, we carried out a genetic screen to identify genes required for qiRNA biogenesis. Factors directly involved in homologous recombination (HR) and chromatin remodeling factors required for HR are essential for qiRNA production. HR is also required for quelling, and quelling is also the result of DNA damage, indicating that quelling and qiRNA production share a common mechanism. Together, our results suggest that DNA damage-triggered HR-based recombination allows the RNAi pathway to recognize repetitive DNA to produce small RNA.
authors: Department of Physiology, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA.
authors: Zhenyu
authors: Z
authors: Zhang
authors: Shwu-Shin
authors: SS
authors: Chang
authors: Zhenying
authors: Z
authors: Zhang
authors: Zhihong
authors: Z
authors: Xue
authors: Hanxing
authors: H
authors: Zhang
authors: Shaojie
authors: S
authors: Li
authors: Yi
authors: Y
authors: Liu
mesh_terms: D042002:Chromatin Assembly and Disassembly; D004249:DNA Damage / Q000235:genetics; D004261:DNA Replication; D004275:DNA, Ribosomal / Q000235:genetics; D059765:Homologous Recombination / Q000235:genetics*; D009491:Neurospora / Q000235:genetics; D012313:RNA / Q000235:genetics / Q000378:metabolism; D034622:RNA Interference; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics*
chemical_list: D004275:DNA, Ribosomal; D012313:RNA