Wu Jianyong, Zhang Meng, Zhang Bingbing, Zhang Xuexian, Guo Liping, Qi Tingxiang, Wang Hailin, Zhang Jinfa, Xing Chaozhu
State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Key Laboratory for Cotton Genetic Improvement, Ministry of Agriculture, 38 Huanghe Dadao, Anyang, 455000, China.
Department of Plant and Environmental Sciences, New Mexico State University, Las Cruces, NM, 88003, USA.
BMC Genomics. 2017 Jun 8;18(1):454. doi: 10.1186/s12864-017-3841-0.
Cytoplasmic male sterility (CMS) conferred by the cytoplasm from Gossypium harknessii (D2) is an important system for hybrid seed production in Upland cotton (G. hirsutum). The male sterility of CMS-D2 (i.e., A line) can be restored to fertility by a restorer (i.e., R line) carrying the restorer gene Rf1 transferred from the D2 nuclear genome. However, the molecular mechanisms of CMS-D2 and its restoration are poorly understood.
In this study, a genome-wide comparative transcriptome analysis was performed to identify differentially expressed genes (DEGs) in flower buds among the isogenic fertile R line and sterile A line derived from a backcross population (BCF) and the recurrent parent, i.e., the maintainer (B line). A total of 1464 DEGs were identified among the three isogenic lines, and the Rf1-carrying Chr_D05 and its homeologous Chr_A05 had more DEGs than other chromosomes. The results of GO and KEGG enrichment analysis showed differences in circadian rhythm between the fertile and sterile lines. Eleven DEGs were selected for validation using qRT-PCR, confirming the accuracy of the RNA-seq results.
Through genome-wide comparative transcriptome analysis, the differential expression profiles of CMS-D2 and its maintainer and restorer lines in Upland cotton were identified. Our results provide an important foundation for further studies into the molecular mechanisms of the interactions between the restorer gene Rf1 and the CMS-D2 cytoplasm.
由哈克尼棉（D2）细胞质赋予的细胞质雄性不育（CMS）是陆地棉（陆地棉）杂交种子生产的重要系统。CMS-D2（即A系）的雄性不育可以通过携带从D2核基因组转移而来的恢复基因Rf1的恢复系（即R系）恢复育性。然而，CMS-D2及其恢复的分子机制尚不清楚。
在本研究中，进行了全基因组比较转录组分析，以鉴定来自回交群体（BCF）和轮回亲本即保持系（B系）的同基因可育R系和不育A系之间花芽中差异表达的基因（DEG）。在这三个同基因系中总共鉴定出1464个DEG，携带Rf1的Chr_D05及其同源的Chr_A05比其他染色体有更多的DEG。GO和KEGG富集分析结果显示可育系和不育系之间在昼夜节律上存在差异。选择11个DEG进行qRT-PCR验证，证实了RNA-seq结果的准确性。
通过全基因组比较转录组分析，确定了陆地棉中CMS-D2及其保持系和恢复系的差异表达谱。我们的结果为进一步研究恢复基因Rf1与CMS-D2细胞质之间相互作用的分子机制提供了重要基础。
