植物学报 ›› 2019, Vol. 54 ›› Issue (1): 46-57.DOI: 10.11983/CBB18045

• 研究报告 • 上一篇    下一篇

异源过表达水稻OsSAPP3基因促进拟南芥叶片衰老

崔胜男1,2,张艺函1,徐凡1,*()   

  1. 1 沈阳农业大学水稻研究所, 农业部东北水稻生物学与遗传育种重点实验室, 北方超级粳稻育种 教育部重点实验室, 沈阳 110866
    2 抚顺四方高级中学, 抚顺 113122
  • 收稿日期:2018-02-12 接受日期:2018-05-21 出版日期:2019-01-30 发布日期:2019-07-31
  • 通讯作者: 徐凡
  • 基金资助:
    国家自然科学基金(31401298)

Heterologous Overexpression of Rice OsSAPP3 Gene Promotes Leaf Senescence in Transgenic Arabidopsis

Shengnan Cui1,2,Yihan Zhang1,Fan Xu1,*()   

  1. 1 Key Laboratory of Northeast Rice Biology and Breeding, Ministry of Agriculture, Key Laboratory of Northern Japonica Rice Genetics and Breedings, Ministry of Education, Rice Research Institute, Shenyang Agriculture University, Shenyang 110866, China
    2 Fushun Sifang Senior High School, Fushun 113122, China
  • Received:2018-02-12 Accepted:2018-05-21 Online:2019-01-30 Published:2019-07-31
  • Contact: Fan Xu

摘要:

蛋白磷酸酶催化的蛋白质可逆磷酸化反应是叶片衰老的关键环节。该研究筛选并克隆了1个新的参与水稻(Oryza sativa)叶片衰老调控的PP2C基因OsSAPP3。研究表明, OsSAPP3的启动子在ProOsSAPP3-GUS转基因拟南芥(Arabidopsis thaliana)的莲座叶中有活性, 并且活性以依赖叶龄方式增加。利用CaMV 35S启动子驱动组成型异源过表达OsSAPP3导致转基因拟南芥无法正常生长。用可诱导型启动子GVG系统驱动OsSAPP3异源过表达导致转基因拟南芥出现莲座叶变小、数量增加、叶片早衰及抽薹开花提前等早衰表型。外源诱导OsSAPP3基因异源过表达后, 利用实时荧光定量PCR检测到SAG12WRKY6NAC2等衰老标志基因显著上调表达。研究结果表明, OsSAPP3是参与水稻叶片衰老的正向调控因子。

关键词: 拟南芥, 叶片衰老, OsSAPP3, 2C型蛋白磷酸酶

Abstract:

Protein phosphatase-catalyzed reversible phosphorylation of proteins is a key aspect of leaf senescence. We screened and cloned a new PP2C gene, OsSAPP3, involved in leaf senescence regulation in rice. The promoter of OsSAPP3 was active in rosette leaves of ProOsSAPP3-GUS transgenic Arabidopsis and its activity increased with leaf age. With heterologous overexpression of OsSAPP3 driven by a CaMV 35S promoter, transgenic Arabidopsis could not grow normally. Therefore, OsSAPP3 heterologous overexpression was induced by the inducible promoter GVG system. Exo- genous inducible heterologous overexpression of OsSAPP3 led to a precocious leaf senescence phenotype in transgenic Arabidopsis including smaller rosette leaves and increased number, premature leaf senescence, and advanced bolting and flowering. Additionally, quantitative RT-PCR showed that exogenous inducible heterologous overexpression of OsSAPP3 upregulated the expression of critical senescence-related transcription factor genes, including SAG12, WRKY6, and NAC2. In summary, OsSAPP3 is a positive factor involved in regulating leaf senescence in rice.

Key words: Arabidopsis, leaf senescence, OsSAPP3, 2C type protein phosphatase