Zhang Qiang, Chen Changzhao, Wang Yaliang, He Mengxing, Li Zhiwen, Shen Lan, Li Qing, Zhu Li, Ren Deyong, Hu Jiang, Gao Zhenyu, Zhang Guangheng, Qian Qian
State Key Lab of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, People's Republic of China.
College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, 321004, People's Republic of China.
Plant Cell Rep. 2023 Feb;42(2):421-431. doi: 10.1007/s00299-022-02968-6. Epub 2022 Dec 28.
OsPPR11 belongs to the P-type PPR protein family and can interact with OsCAF2 to regulate Group II intron splicing and affect chloroplast development in rice. Pentatricopeptide repeat (PPR) proteins participate in chloroplasts or mitochondria group II introns splicing in plants. The PPR protein family contains 491 members in rice, but most of their functions are unknown. In this study, we identified a nuclear gene encoding the P-type PPR protein OsPPR11 in chloroplasts. The qRT-PCR analysis demonstrated that OsPPR11 was expressed in all plant tissues, but leaves had the highest expression. The osppr11 mutants had yellowing leaves and a lethal phenotype that inhibited chloroplast development and photosynthesis-related gene expression and reduced photosynthesis-related protein accumulation in seedlings. Moreover, photosynthetic complex accumulation decreased significantly in osppr11 mutants. The OsPPR11 is required for ndhA, and ycf3-1 introns splicing and interact with CRM family protein OsCAF2, suggesting that these two proteins may form splicing complexes to regulate group II introns splicing. Further analysis revealed that OsCAF2 interacts with OsPPR11 through the N-terminus. These results indicate that OsPPR11 is essential for chloroplast development and function by affecting group II intron splicing in rice.
OsPPR11属于P型PPR蛋白家族，可与OsCAF2相互作用，调控II类内含子剪接，影响水稻叶绿体发育。五肽重复序列（PPR）蛋白参与植物叶绿体或线粒体II类内含子剪接。水稻中的PPR蛋白家族包含491个成员，但其大多数功能尚不清楚。在本研究中，我们鉴定了一个在叶绿体中编码P型PPR蛋白OsPPR11的核基因。qRT-PCR分析表明，OsPPR11在所有植物组织中均有表达，但在叶片中表达量最高。osppr11突变体叶片发黄，具有致死表型，抑制叶绿体发育和光合作用相关基因表达，并减少幼苗中光合作用相关蛋白积累。此外，osppr11突变体中光合复合体积累显著减少。OsPPR11是ndhA和ycf3-1内含子剪接所必需的，并与CRM家族蛋白OsCAF2相互作用，表明这两种蛋白可能形成剪接复合体来调控II类内含子剪接。进一步分析表明，OsCAF2通过N端与OsPPR11相互作用。这些结果表明，OsPPR11通过影响水稻II类内含子剪接对叶绿体发育和功能至关重要。
