title: A DNA2 Homolog Is Required for DNA Damage Repair, Cell Cycle Regulation, and Meristem Maintenance in Plants.
abstract: Plant meristem cells divide and differentiate in a spatially and temporally regulated manner, ultimately giving rise to organs. In this study, we isolated the Arabidopsis jing he sheng 1 (jhs1) mutant, which exhibited retarded growth, an abnormal pattern of meristem cell division and differentiation, and morphological defects such as fasciation, an irregular arrangement of siliques, and short roots. We identified JHS1 as a homolog of human and yeast DNA Replication Helicase/Nuclease2, which is known to be involved in DNA replication and damage repair. JHS1 is strongly expressed in the meristem of Arabidopsis. The jhs1 mutant was sensitive to DNA damage stress and had an increased DNA damage response, including increased expression of genes involved in DNA damage repair and cell cycle regulation, and a higher frequency of homologous recombination. In the meristem of the mutant plants, cell cycle progression was delayed at the G2 or late S phase and genes essential for meristem maintenance were misregulated. These results suggest that JHS1 plays an important role in DNA replication and damage repair, meristem maintenance, and development in plants.
authors.affiliation: College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China (N.J., X.L., H.G.).
authors.forename: Ning
authors.initials: N
authors.lastname: Jia
authors.affiliation: College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China (N.J., X.L., H.G.).
authors.forename: Xiaomin
authors.initials: X
authors.lastname: Liu
authors.affiliation: College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China (N.J., X.L., H.G.) gaohongbo@bjfu.edu.cn.
authors.forename: Hongbo
authors.initials: H
authors.lastname: Gao
mesh_terms: D017360:Arabidopsis / Q000166:cytology* / Q000235:genetics / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002453:Cell Cycle / Q000502:physiology; D004265:DNA Helicases / Q000737:chemistry; D004260:DNA Repair / Q000502:physiology*; D018506:Gene Expression Regulation, Plant; D059765:Homologous Recombination; D018519:Meristem / Q000502:physiology*; D009154:Mutation; D030821:Plants, Genetically Modified; D017386:Sequence Homology, Amino Acid
chemical_list: D029681:Arabidopsis Proteins; D004265:DNA Helicases; C509908:DNA2 protein, human