title: SPL33, encoding an eEF1A-like protein, negatively regulates cell death and defense responses in rice.
abstract: Lesion-mimic mutants are useful to dissect programmed cell death and defense-related pathways in plants. Here we identified a new rice lesion-mimic mutant, spotted leaf 33 (spl33) and cloned the causal gene by a map-based cloning strategy. SPL33 encodes a eukaryotic translation elongation factor 1 alpha (eEF1A)-like protein consisting of a non-functional zinc finger domain and three functional EF-Tu domains. spl33 exhibited programmed cell death-mediated cell death and early leaf senescence, as evidenced by analyses of four histochemical markers, namely H2O2 accumulation, cell death, callose accumulation and TUNEL-positive nuclei, and by four indicators, namely loss of chlorophyll, breakdown of chloroplasts, down-regulation of photosynthesis-related genes, and up-regulation of senescence-associated genes. Defense responses were induced in the spl33 mutant, as shown by enhanced resistance to both the fungal pathogen Magnaporthe oryzae and the bacterial pathogen Xanthomonas oryzae pv. oryzae and by up-regulation of defense response genes. Transcriptome analysis of the spl33 mutant and its wild type provided further evidence for the biological effects of loss of SPL33 function in cell death, leaf senescence and defense responses in rice. Detailed analyses showed that reactive oxygen species accumulation may be the cause of cell death in the spl33 mutant, whereas uncontrolled activation of multiple innate immunity-related receptor genes and signaling molecules may be responsible for the enhanced disease resistance observed in spl33. Thus, we have demonstrated involvement of an eEF1A-like protein in programmed cell death and provided a link to defense responses in rice.
authors.affiliation: Institute of Crop Science, Chinese Academy of Agriculture Sciences/National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081, China.
authors.forename: Shuai
authors.initials: S
authors.lastname: Wang
authors.affiliation: Institute of Crop Science, Chinese Academy of Agriculture Sciences/National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081, China.
authors.forename: Cailin
authors.initials: C
authors.lastname: Lei
authors.affiliation: Institute of Crop Science, Chinese Academy of Agriculture Sciences/National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081, China.
authors.forename: Jiulin
authors.initials: J
authors.lastname: Wang
authors.affiliation: Institute of Crop Science, Chinese Academy of Agriculture Sciences/National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Ma
authors.affiliation: Institute of Crop Science, Chinese Academy of Agriculture Sciences/National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081, China.
authors.forename: Sha
authors.initials: S
authors.lastname: Tang
authors.affiliation: Institute of Crop Science, Chinese Academy of Agriculture Sciences/National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081, China.
authors.forename: Chunlian
authors.initials: C
authors.lastname: Wang
authors.affiliation: Institute of Crop Science, Chinese Academy of Agriculture Sciences/National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081, China.
authors.forename: Kaijun
authors.initials: K
authors.lastname: Zhao
authors.affiliation: Institute of Crop Science, Chinese Academy of Agriculture Sciences/National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Tian
authors.affiliation: Key Laboratory of Crop Genetics and Germplasm Enhancement/Jiangsu Provincial Center of Plant Gene Engineering, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Huan
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Institute of Crop Science, Chinese Academy of Agriculture Sciences/National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081, China.
authors.forename: Changyan
authors.initials: C
authors.lastname: Qi
authors.affiliation: Institute of Crop Science, Chinese Academy of Agriculture Sciences/National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081, China.
authors.forename: Zhijun
authors.initials: Z
authors.lastname: Cheng
authors.affiliation: Institute of Crop Science, Chinese Academy of Agriculture Sciences/National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Institute of Crop Science, Chinese Academy of Agriculture Sciences/National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081, China.
authors.forename: Xiuping
authors.initials: X
authors.lastname: Guo
authors.affiliation: Key Laboratory of Crop Genetics and Germplasm Enhancement/Jiangsu Provincial Center of Plant Gene Engineering, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Linglong
authors.initials: L
authors.lastname: Liu
authors.affiliation: Institute of Crop Science, Chinese Academy of Agriculture Sciences/National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081, China.
authors.forename: Chuanyin
authors.initials: C
authors.lastname: Wu
authors.affiliation: Institute of Crop Science, Chinese Academy of Agriculture Sciences/National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081, China.|Key Laboratory of Crop Genetics and Germplasm Enhancement/Jiangsu Provincial Center of Plant Gene Engineering, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Jianmin
authors.initials: J
authors.lastname: Wan
mesh_terms: D000595:Amino Acid Sequence; D017209:Apoptosis; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D009928:Organ Specificity; D012275:Oryza / Q000235:genetics / Q000276:immunology / Q000502:physiology*; D010802:Phylogeny; D057865:Plant Immunity; D018515:Plant Leaves / Q000276:immunology / Q000378:metabolism; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D016415:Sequence Alignment
chemical_list: D018076:DNA, Complementary; D010940:Plant Proteins
keywords: Defense responses; Oryza sativa; SPL33.; eukaryotic translation elongation factor 1 alpha (eEF1A); lesion-mimic mutant; programed cell death