State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.
The Municipal Key Laboratory of the Molecular Genetics of Hybrid Wheat, Institute of Hybrid Wheat, Beijing Academy of Agriculture and Forestry Sciences, Beijing, 100097, China.
Nat Commun. 2023 Oct 25;14(1):6789. doi: 10.1038/s41467-023-42269-4.
Cold stress affects rice growth and productivity. Defects in the plastid-localized pseudouridine synthase OsPUS1 affect chloroplast ribosome biogenesis, leading to low-temperature albino seedlings and accumulation of reactive oxygen species (ROS). Here, we report an ospus1-1 suppressor, sop10. SOP10 encodes a mitochondria-localized pentatricopeptide repeat protein. Mutations in SOP10 impair intron splicing of the nad4 and nad5 transcripts and decrease RNA editing efficiency of the nad2, nad6, and rps4 transcripts, resulting in deficiencies in mitochondrial complex I, thus decrease ROS generation and rescuing the albino phenotype. Overexpression of different compartment-localized superoxide dismutases (SOD) genes in ospus1-1 reverses the ROS over-accumulation and albino phenotypes to various degrees, with Mn-SOD reversing the best. Mutation of SOP10 in indica rice varieties enhances cold tolerance with lower ROS levels. We find that the mitochondrial superoxide plays a key role in rice cold responses, and identify a mitochondrial superoxide modulating factor, informing efforts to improve rice cold tolerance.
冷胁迫会影响水稻的生长和产量。质体定位的假尿嘧啶合酶 OsPUS1 的缺陷会影响叶绿体核糖体的生物发生，导致低温白化苗和活性氧（ROS）的积累。在这里，我们报告了一个 ospus1-1 抑制子 sop10。SOP10 编码一个定位于线粒体的五肽重复蛋白。SOP10 的突变会损害 nad4 和 nad5 转录物的内含子剪接，并降低 nad2、nad6 和 rps4 转录物的 RNA 编辑效率，导致线粒体复合物 I 的缺陷，从而减少 ROS 的产生并挽救白化表型。在 ospus1-1 中过表达不同区室定位的超氧化物歧化酶（SOD）基因在不同程度上逆转了 ROS 的过度积累和白化表型，其中 Mn-SOD 的逆转效果最好。在籼稻品种中突变 SOP10 会增强对低温的耐受性，同时降低 ROS 水平。我们发现线粒体超氧阴离子在水稻冷响应中起关键作用，并鉴定出一种线粒体超氧阴离子调节因子，为提高水稻耐冷性提供了信息。
