title: XRCC3 is essential for proper double-strand break repair and homologous recombination in rice meiosis.
abstract: RAD51 paralogues play important roles in the assembly and stabilization of RAD51 nucleoprotein filaments, which promote homologous pairing and strand exchange reactions in organisms ranging from yeast to vertebrates. XRCC3, a RAD51 paralogue, has been characterized in budding yeast, mouse, and Arabidopsis. In the present study, XRCC3 in rice was identified and characterized. The rice xrcc3 mutant exhibited normal vegetative growth but complete male and female sterility. Cytological investigations revealed that homologous pairing and synapsis were severely disrupted in the mutant. Meiotic chromosomes were frequently entangled from diplotene to metaphase I, resulting in chromosome fragmentation at anaphase I. The immunostaining signals from γH2AX were regular, implying that double-strand break (DSB) formation was normal in xrcc3 meiocytes. However, COM1 was not detected on early prophase I chromosomes, suggesting that the DSB end-processing system was destroyed in the mutant. Moreover, abnormal chromosome localization of RAD51C, DMC1, ZEP1, ZIP4, and MER3 was observed in xrcc3. Taken together, the results suggest that XRCC3 plays critical roles in both DSB repair and homologous chromosome recombination during rice meiosis.
authors.affiliation: Key Laboratory of Plant Functional Genomics of Ministry of Education/Jiangsu Key Laboratory of Crop Genetics and Physiology/ Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China.
authors.forename: Bingwei
authors.initials: B
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Plant Genomics and Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Mo
authors.initials: M
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Plant Genomics and Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Ding
authors.initials: D
authors.lastname: Tang
authors.affiliation: State Key Laboratory of Plant Genomics and Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Yafei
authors.initials: Y
authors.lastname: Li
authors.affiliation: Key Laboratory of Plant Functional Genomics of Ministry of Education/Jiangsu Key Laboratory of Crop Genetics and Physiology/ Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China.
authors.forename: Meng
authors.initials: M
authors.lastname: Xu
authors.affiliation: Key Laboratory of Plant Functional Genomics of Ministry of Education/Jiangsu Key Laboratory of Crop Genetics and Physiology/ Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China.
authors.forename: Minghong
authors.initials: M
authors.lastname: Gu
authors.affiliation: State Key Laboratory of Plant Genomics and Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China hxyu@yzu.edu.cn zkcheng@genetics.ac.cn.
authors.forename: Zhukuan
authors.initials: Z
authors.lastname: Cheng
authors.affiliation: Key Laboratory of Plant Functional Genomics of Ministry of Education/Jiangsu Key Laboratory of Crop Genetics and Physiology/ Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China hxyu@yzu.edu.cn zkcheng@genetics.ac.cn.
authors.forename: Hengxiu
authors.initials: H
authors.lastname: Yu
mesh_terms: D053903:DNA Breaks, Double-Stranded; D004260:DNA Repair; D018744:DNA, Plant / Q000235:genetics* / Q000378:metabolism; D059765:Homologous Recombination; D008540:Meiosis; D012275:Oryza / Q000235:genetics* / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D013573:Synaptonemal Complex / Q000235:genetics*
chemical_list: D018744:DNA, Plant; D010940:Plant Proteins
keywords: DSB; XRCC3.; homologous recombination; meiosis; rice