College of Agronomy, National Key Laboratory of Crop Science in Wheat and Maize, Henan Agricultural University, Zhengzhou, China.
College of Agronomy, Henan Science and Technology University, Luoyang, China.
Plant Genome. 2020 Jul;13(2):e20022. doi: 10.1002/tpg2.20022. Epub 2020 May 22.
The maize C system of cytoplasmic male sterility (CMS) and its fertility restoration gene Rf4 have been widely used for maize hybrid production; however, the underlying mechanism is still uncertain. The sterility factor functions in mitochondria, where it interacts directly or indirectly with the restorer. Mitoproteomics can capture all participants involved in CMS and restoration at the organelle level. In the present study, we identified and quantified anther mitochondrial proteins from CMS, maintainer and restorer lines. We obtained 14,528 unique peptides belonging to 3,369 proteins. Comparative analysis of 1840 high-confidence proteins revealed 68 were differentially accumulated proteins likely involved in CMS or its restoration within mitochondria. These proteins were mainly associated with fatty acid metabolism, amino acid metabolism and protein-processing pathways. These results suggest that an energy deficiency caused by the sterility factor hinders other proteins or protein complexes required for pollen development through nuclear-mitochondrial interaction. The restorer factor may boost the energy generation by activating alternative metabolic pathways and by improving the post-translation processing efficiency of proteins in energy-producing complexes to restore pollen fertility. Our findings may aid detailed molecular analysis and contribute to a better understanding of maize CMS-C restoration and sterility.
玉米细胞质雄性不育（CMS）的 C 系统及其育性恢复基因 Rf4 已被广泛应用于玉米杂交种生产；然而，其潜在机制仍不清楚。不育因子在线粒体中发挥作用，它直接或间接与恢复因子相互作用。线粒体蛋白质组学可以在细胞器水平上捕获与 CMS 和恢复相关的所有参与者。在本研究中，我们从 CMS、保持系和恢复系的花药线粒体中鉴定和定量了蛋白质。我们获得了 14528 个独特的肽段，属于 3369 种蛋白质。对 1840 种高可信度蛋白质的比较分析表明，有 68 种差异积累蛋白可能与线粒体中的 CMS 或其恢复有关。这些蛋白质主要与脂肪酸代谢、氨基酸代谢和蛋白质加工途径有关。这些结果表明，不育因子引起的能量缺乏通过核-线粒体相互作用阻碍了花粉发育所需的其他蛋白质或蛋白质复合物。恢复因子可能通过激活替代代谢途径和提高能量产生复合物中蛋白质的翻译后加工效率来增加能量产生，从而恢复花粉育性。我们的研究结果可能有助于详细的分子分析，并有助于更好地理解玉米 CMS-C 恢复和不育。
