State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Agriculture, Guangxi University, Nanning 530004, China.
National Key Laboratory of Non-Food Biomass and Enzyme Technology, National Engineering Research Center for Non-Food Biorefinery, Institute of Grand Health, Guangxi Academy of Sciences, Nanning 530007, China.
Int J Mol Sci. 2024 Nov 14;25(22):12257. doi: 10.3390/ijms252212257.
Cytoplasmic male sterile (CMS) systems have great potential in hybrid seed production in many plants. However, the incompatibility between the cytoplasmic and nuclear genes and the availability of fewer CMS lines limit the system's application in cotton heterosis. Therefore, the present study sequenced the mitochondrial (mt) genomes of a novel cotton ( L.) CMS line J4A and its cytoplasmic nuclear homologous maintainer line J4B to investigate the mechanism underlying CMS and improve its application. A novel CMS gene, , was identified in the CMS line. Ectopic expression of in suppressed growth, while its overexpression in Arabidopsis, rice, tobacco, and cotton led to complete or partial male sterility. Further analysis of anthers revealed mt disruption in J4A with higher levels of hydrogen peroxide (HO) and malondialdehyde (MDA), but lower levels of ATP and ribosomal protein (RP) than in J4B. Finally, a membrane-based yeast two-hybrid (MYTH) assay and bimolecular fluorescence complementation (BiFC) assays demonstrated that orf116b probably interacts with an anther-specific protein, LAT52. These observations collectively proved that orf116b is associated with early and stable pollen abortion in cotton, providing a foundation for further research on cotton fertility restoration and heterosis breeding.
细胞质雄性不育（CMS）系统在许多植物的杂种种子生产中具有巨大的潜力。然而，细胞质和核基因之间的不兼容性以及 CMS 系的可用性较少限制了该系统在棉花杂种优势中的应用。因此，本研究对一种新型棉花（L.）CMS 系 J4A 及其细胞质核同保持系 J4B 的线粒体（mt）基因组进行了测序，以探讨 CMS 的机制并提高其应用。在 CMS 系中鉴定到一个新的 CMS 基因 。在 中异位表达 抑制生长，而在拟南芥、水稻、烟草和棉花中的过表达导致完全或部分雄性不育。对花药的进一步分析表明，J4A 中的 mt 中断，HO 和 MDA 水平较高，而 ATP 和核糖体蛋白（RP）水平较低。最后，基于膜的酵母双杂交（MYTH）测定和双分子荧光互补（BiFC）测定表明，orf116b 可能与花药特异性蛋白 LAT52 相互作用。这些观察结果共同证明 orf116b 与棉花中早期和稳定的花粉败育有关，为进一步研究棉花育性恢复和杂种优势育种提供了基础。
