title: Replication protein A (RPA1a) is required for meiotic and somatic DNA repair but is dispensable for DNA replication and homologous recombination in rice.
abstract: Replication protein A (RPA), a highly conserved single-stranded DNA-binding protein in eukaryotes, is a stable complex comprising three subunits termed RPA1, RPA2, and RPA3. RPA is required for multiple processes in DNA metabolism such as replication, repair, and homologous recombination in yeast (Saccharomyces cerevisiae) and human. Most eukaryotic organisms, including fungi, insects, and vertebrates, have only a single RPA gene that encodes each RPA subunit. Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa), however, possess multiple copies of an RPA gene. Rice has three paralogs each of RPA1 and RPA2, and one for RPA3. Previous studies have established their biochemical interactions in vitro and in vivo, but little is known about their exact function in rice. We examined the function of OsRPA1a in rice using a T-DNA insertional mutant. The osrpa1a mutants had a normal phenotype during vegetative growth but were sterile at the reproductive stage. Cytological examination confirmed that no embryo sac formed in female meiocytes and that abnormal chromosomal fragmentation occurred in male meiocytes after anaphase I. Compared with wild type, the osrpa1a mutant showed no visible defects in mitosis and chromosome pairing and synapsis during meiosis. In addition, the osrpa1a mutant was hypersensitive to ultraviolet-C irradiation and the DNA-damaging agents mitomycin C and methyl methanesulfonate. Thus, our data suggest that OsRPA1a plays an essential role in DNA repair but may not participate in, or at least is dispensable for, DNA replication and homologous recombination in rice.
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Yuxiao
authors.initials: Y
authors.lastname: Chang
authors.forename: Liang
authors.initials: L
authors.lastname: Gong
authors.forename: Wenya
authors.initials: W
authors.lastname: Yuan
authors.forename: Xingwang
authors.initials: X
authors.lastname: Li
authors.forename: Guoxing
authors.initials: G
authors.lastname: Chen
authors.forename: Xianghua
authors.initials: X
authors.lastname: Li
authors.forename: Qifa
authors.initials: Q
authors.lastname: Zhang
authors.forename: Changyin
authors.initials: C
authors.lastname: Wu
mesh_terms: D032461:Chromosomes, Plant / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D053938:DNA Fragmentation / Q000187:drug effects / Q000528:radiation effects; D004260:DNA Repair / Q000187:drug effects / Q000528:radiation effects; D004261:DNA Replication / Q000187:drug effects / Q000528:radiation effects; D004269:DNA, Bacterial / Q000235:genetics; D017343:Genes, Plant / Q000235:genetics; D005816:Genetic Complementation Test; D055993:Germ Cells, Plant / Q000187:drug effects / Q000254:growth & development / Q000528:radiation effects; D008540:Meiosis / Q000187:drug effects / Q000528:radiation effects; D008741:Methyl Methanesulfonate / Q000494:pharmacology; D016685:Mitomycin / Q000494:pharmacology; D008938:Mitosis / Q000187:drug effects / Q000528:radiation effects; D009153:Mutagens / Q000494:pharmacology; D009154:Mutation / Q000235:genetics; D012275:Oryza / Q000166:cytology* / Q000187:drug effects / Q000196:embryology / Q000235:genetics*; D010641:Phenotype; D010940:Plant Proteins / Q000378:metabolism; D030821:Plants, Genetically Modified; D011058:Pollen / Q000166:cytology / Q000187:drug effects / Q000528:radiation effects; D034622:RNA Interference / Q000187:drug effects / Q000528:radiation effects; D011995:Recombination, Genetic / Q000187:drug effects / Q000528:radiation effects; D051716:Replication Protein A / Q000378:metabolism*; D014466:Ultraviolet Rays
chemical_list: D004269:DNA, Bacterial; D009153:Mutagens; D010940:Plant Proteins; D051716:Replication Protein A; C036483:T-DNA; D016685:Mitomycin; D008741:Methyl Methanesulfonate