The pentatricopeptide repeat protein EMB1270 interacts with CFM2 to splice specific group Ⅱ introns in Arabidopsis chloroplasts  

作　　者：Li Zhang Jingli Chen Liqun Zhang Ying Wei Yajuan Li Xinyun Xu Hui Wu Zhong‐Nan Yang Jirong Huang Fenhong Hu Weihua Huang Yong‐Lan Cui 

机构地区：[1]Shanghai Key Laboratory of Plant Molecular Sciences,Development Center of Plant Germplasm Resources,College of Life Sciences,Shanghai Normal University,Shanghai 200234,China

出　　处：《Journal of Integrative Plant Biology》2021年第11期1952-1966,共15页植物学报（英文版）

基　　金：This study was supported by the National Natural Science Foundation of China(31100180,31470337,31570231);Shanghai Natural Science Foundation(18ZR1428200);The Fund of Innovation Program of Shanghai Municipal Education Commission(2021-01-07-00-02-E00117);Shanghai Engineering Research Center of Plant Germplasm Resources(17DZ2252700)。

摘　　要：Chloroplast biogenesis requires the coordinated expression of chloroplast and nuclear genes.Here, we show that EMB1270, a plastid-localized pentatricopeptide repeat(PPR) protein, is required for chloroplast biogenesis in Arabidopsis thaliana.Knockout of EMB1270 led to embryo arrest,whereas a mild knockdown mutant of EMB1270 displayed a virescent phenotype. Almost no photosynthetic proteins accumulated in the albino emb1270 knockout mutant. By contrast, in the emb1270 knockdown mutant, the levels of ClpP1 and photosystem I(PSI) subunits were significantly reduced, whereas the levels of photosystem II(PSII) subunits were normal. Furthermore, the splicing efficiencies of the clpP1.2,ycf3.1, ndhA, and ndhB plastid introns were dramatically reduced in both emb1270 mutants. RNA immunoprecipitation revealed that EMB1270 associated with these introns in vivo. In an RNA electrophoretic mobility shift assay(REMSA), a truncated EMB1270 protein containing the 11 Nterminal PPR motifs bound to the predicted sequences of the clpP1.2, ycf3.1, and ndhA introns.In addition, EMB1270 specifically interacted with CRM Family Member 2(CFM2). Given that CFM2 is known to be required for splicing the same plastid RNAs, our results suggest that EMB1270 associates with CFM2 to facilitate the splicing of specific group II introns in Arabidopsis.

关 键 词：Arabidopsis thaliana CRM Family Member 2 CHLOROPLAST EMB1270 intron splicing pentatricopeptide repeat protein 

分 类 号：Q943.2[生物学—植物学]