甘蔗PsbR亚基应答SCMV侵染及其与SCMV-6K2的互作  

Sugarcane PsbR subunit response to SCMV infection and its interaction with SCMV-6K2

作　　者：张海 程光远[1] 杨宗桃 刘淑娴 商贺阳 黄国强[1] 徐景升[1] ZHANG Hai;CHENG Guang-Yuan;YANG Zong-Tao;LIU Shu-Xian;SHANG He-Yang;HUANGGuo-Qiang;XU Jing-Sheng(National Engineering Research Center for Sugarcane/Key Laboratory of Sugarcane Biology and Genetic Breeding,Ministry of Agriculture and Rural Affairs/Key Laboratory of Ministry of Education for Genetics,Breeding and Multiple Utilization of Crops/Fujian Agriculture and Forestry University,Fuzhou 350002,Fujian,China)

机构地区：[1]福建农林大学国家甘蔗工程技术研究中心/农业农村部福建甘蔗生物学与遗传育种重点实验室/教育部作物遗传育种与综合利用重点实验室,福建福州350002

出　　处：《作物学报》2021年第8期1522-1530,共9页Acta Agronomica Sinica

基　　金：国家自然科学基金项目(31971991);福建农林大学科技创新基金项目(CXZX2018026);福建省科技厅引导性项目(2017N0003)资助。

摘　　要：光系统II(Photosystem II,PSII)的PsbR亚基对于放氧复合体(oxygen-evolving complex)的组装和稳定具有至关重要的作用。本课题组前期克隆了甘蔗(Saccharum spp.hybrid)的PsbR亚基编码基因,命名为ScPsbR,并利用酵母双杂交技术(yeast two hybrid,Y2H)验证了ScPsbR与甘蔗花叶病毒(Sugarcane mosaic virus,SCMV)编码蛋白6K2的互作。本研究通过生物信息学分析表明,ScPsbR具有典型的PsbR亚基结构域,无信号肽,具有1个跨膜结构域,为稳定的疏水性蛋白。系统进化树分析表明,该蛋白在C3和C4植物中存在明显的分化。亚细胞定位试验表明,ScPsbR定位于叶绿体且与SCMV-6K2共定位。双分子荧光互补(bimolecular fluorescence complementation,BiFC)试验进一步验证了ScPsbR与SCMV-6K2的互作。实时荧光定量PCR检测表明,ScPsbR基因表达具有显著的组织特异性,在根和茎中表达极少,未成熟叶片和初衰叶中次之,成熟叶片中相对表达量最高;SCMV侵染显著影响ScPsbR基因表达,ScPsbR基因在侵染0~12 h显著上调,侵染1~5 d下调至略低于对照的水平,但差异不显著,侵染7~15 d显著下调。The PsbR subunit of photosystem II(PSII)plays a vital role in the assembly and stability of the oxygen-evolving complex.In the previous study,we cloned the coding sequence of the PsbR subunit from sugarcane(Saccharum spp.hybrid)and designated it as ScPsbR.The interaction between ScPsbR and 6K2 protein encoded by Sugarcane mosaic virus(SCMV)was verified by yeast two-hybrid technology.In this study,bioinformatics analysis indicated ScPsbR protein was found to possess a canonical subunit domain of PsbR and a transmembrane domain without signal peptide,and be a stable hydrophobic protein.Phylogenetic tree analysis indicated obvious divergence between C3 and C4 plants for the PsbRs.Subcellular localization experiments suggested that ScPsbR was localized and co-localized with SCMV-6K2 to the chloroplast.The interaction of ScPsbR with the SCMV-6K2 was further verified by bimolecular fluorescence complementation assays.Real-time quantitative PCR results indicated that ScPsbR gene was tissue-specific in sugarcane plants.There was almost no expression of ScPsbR gene in the roots or stems,with increased expression level in the senescing leaves and immature leaves,and the highest expression level in mature leaves.However,the expression level of ScPsbR was significantly changed under the challenged of SCMV.During the infection of SCMV,ScPsbR was significantly up-regulated at 0–12 hour(s)and reduced to a level slightly lower than that of the control at 1–5 days with no significant differences,then significantly down-regulated in 7–15 days.

关 键 词：PsbR亚基 甘蔗花叶病毒 6K2 蛋白互作 

分 类 号：S435.661[农业科学—农业昆虫与害虫防治]