title: STRIPE2 encodes a putative dCMP deaminase that plays an important role in chloroplast development in rice.
abstract: Mutants with abnormal leaf coloration are good genetic materials for understanding the mechanism of chloroplast development and chlorophyll biosynthesis. In this study, a rice mutant st2 (stripe2) with stripe leaves was identified from the γ-ray irradiated mutant pool. The st2 mutant exhibited decreased accumulation of chlorophyll and aberrant chloroplasts. Genetic analysis indicated that the st2 mutant was controlled by a single recessive locus. The ST2 gene was finely confined to a 27-kb region on chromosome 1 by the map-based cloning strategy and a 5-bp deletion in Os01g0765000 was identified by sequence analysis. The deletion happened in the joint of exon 3 and intron 3 and led to new spliced products of mRNA. Genetic complementation confirmed that Os01g0765000 is the ST2 gene. We found that the ST2 gene was expressed ubiquitously. Subcellular localization assay showed that the ST2 protein was located in mitochondria. ST2 belongs to the cytidine deaminase-like family and possibly functions as the dCMP deaminase, which catalyzes the formation of dUMP from dCMP by deamination. Additionally, exogenous application of dUMP could partially rescue the st2 phenotype. Therefore, our study identified a putative dCMP deaminase as a novel regulator in chloroplast development for the first time.
authors.affiliation: National Key Laboratory of Plant Molecular Genetics and National Center of Plant Gene Research, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Xu
authors.affiliation: National Key Laboratory of Plant Molecular Genetics and National Center of Plant Gene Research, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China.
authors.forename: Yiwen
authors.initials: Y
authors.lastname: Deng
authors.affiliation: National Key Laboratory of Plant Molecular Genetics and National Center of Plant Gene Research, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China.
authors.forename: Qun
authors.initials: Q
authors.lastname: Li
authors.affiliation: China National Rice Research Institute, Hangzhou 31006, China. Electronic address: ricezxd@126.com.
authors.forename: Xudong
authors.initials: X
authors.lastname: Zhu
authors.affiliation: National Key Laboratory of Plant Molecular Genetics and National Center of Plant Gene Research, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China. Electronic address: zhhe@sibs.ac.cn.
authors.forename: Zuhua
authors.initials: Z
authors.lastname: He
mesh_terms: D002736:Chloroplasts / Q000378:metabolism*; D002874:Chromosome Mapping; D003844:DCMP Deaminase / Q000378:metabolism*; D009154:Mutation; D012275:Oryza / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D010641:Phenotype; D010940:Plant Proteins / Q000378:metabolism*
chemical_list: D010940:Plant Proteins; D003844:DCMP Deaminase
keywords: Chloroplast development; Oryza sativa; dCMP deaminase; stripe2