1. 山西农业大学农业基因资源研究中心 / 农业农村部黄土高原作物基因资源与种质创制重点实验室; 2. 南京农业大学农学院 / 国家大豆改良中心
1. Center for Agricultural Genetic Resources Research，Shanxi Agricultural University / Key Laboratory of Crop Gene Resources and Germplasm Enhancement on Loess Plateau of Ministry of Agriculture and Rural Affairs; 2. College of Agriculture，Nanjing Agricultural University / National Center for Soybean Improvement
Shanxi Provincial General Youth Fund（201901D211565）；Shanxi Academy of Agricultural Sciences Excellent Youth Fund （YCX2020YQ58）；Shanxi Agricultural University Biological Breeding Engineering Project（YZGC147）；Shanxi Provincial Science and Technology Innovation Project of Colleges and Universities（2021L091）
恢复系的恢复能力在三系杂种F1的育性稳定中发挥着重要的作用。本研究以相同不育系为母本和不同恢复能力的强、弱恢复系为父本配制的2个大豆细胞质雄性不育杂种F1为研究对象，在开花期对其不同大小的混合花芽进行转录组测序。经比较分析，共筛选出2060个差异表达基因（Differentially expressed genes, DEGs），其中相对以强恢复系为父本配制的杂种F1，在弱恢复系为父本配制的杂种F1中1446个DEGs下调表达，614个DEGs上调表达。qRT-PCR分析验证RNA-Seq结果是可靠的。对差异表达基因进行生物信息学分析，GO富集分析表明细胞外围、果胶酯酶抑制剂活性、果胶酯酶活性、细胞壁和外部封装结构等功能为主要的差异生物学功能；KEGG通路富集分析表明戊糖葡萄糖醛酸相互转化、植物病原相互作用和糖酵解/糖异生等通路为主要的差异代谢通路。根据差异转录学分析结果结合相关文献报道，推测大豆细胞质雄性不育杂种F1的育性稳定性与花粉细胞壁发育、碳水化合物代谢和植物病原相互作用等相关基因有关，当环境条件变化导致其功能平衡打破时，将会出现不育及育性发生转变。本研究为从育性稳定性方面了解大豆细胞质雄性不育及育性恢复的分子机理提供了有价值的信息。
The restoring ability of restorer lines plays an important role in the fertility stability of three line F1 hybrids. In this study, two soybean cytoplasmic male sterile F1 hybrids, which were produced with the same male sterile line pollinated by restorer lines showing strong and weak different restoring ability, respectively, were used. The transcriptome sequencing of mixed flower buds of different sizes was carried out at the flowering stage. Through comparative analysis, according to "p-value < 0.05 and | log2foldchange | > 1" as the threshold in F1 hybrid (weak restorer) if compared to that in F1 hybrid (strong restorer), 2060 differentially expressed genes (DEGs) were identified including 1446 and 614 DEGs were down-regulated and up-regulated, respectively. The transcripts of several genes using quantitative real-time PCR (qRT-PCR) analysis were coincident with the results of RNA sequencing (RNA-Seq). The significance enrichment analysis of gene ontology (GO) showed that the main differential biological functions were cell periphery, pectinesterase inhibitor activity, pectinesterase activity, cell wall and external packaging structure. The enrichment analysis of kyoto encyclopedia of genes and genomes (KEGG) pathway showed that the main differential metabolic pathways were pentose and glucuronate interconversions, plant pathogen interaction and glycolysis / gluconeogenesis. According to the results of differential transcriptional genes analysis and literature reports, it is speculated that the fertility stability of soybean cytoplasmic male sterile F1 hybrid was related to the genes involved in pollen cell wall development, carbohydrate metabolism and plant pathogen interaction. When the functional balance was challenged due to the changes of environmental conditions, the sterility and fertility would be switched. Collectively, this study provided valuable information for understanding the molecular mechanism of cytoplasmic male sterility and fertility restoration in soybean from the aspect of fertility stability.