A combined small RNA and transcriptome sequencing analysis reveal regulatory roles of miRNAs during anther development of Upland cotton carrying cytoplasmic male sterile Gossypium harknessii (D2) cytoplasm

作者：Zhang, Bingbing; Zhang, Xuexian; Liu, Guoyuan; Guo, Liping; Qi, Tingxiang; Zhang, Meng; Li, Xue; Wang, Hailin; Tang, Huini; Qiao, Xiuqin; Pei, Wenfeng; Shahzad, Kashif; Xing, Chaozhu^*; Zhang, Jinfa^*; Wu, Jianyong^*

来源：BMC Plant Biology, 2018, 18(1): 242.

DOI：10.1186/s12870-018-1446-7

• Upland cotton
• CMS-D2
• miRNA-target pair
• Restorer gene
• High-throughput sequencing

Background: Cytoplasmic male sterility (CMS) in flowering plants is usually caused by incompatibility between mitochondrial and nuclear genomes, and can be restored by nuclear genes known as restorer-of-fertility (Rt). Although the CMS/Rf system is useful and convenient for economic production of commercial hybrid seed, the molecular mechanisms of CMS occurrence and fertility restoration in cotton are unclear.
Results: Here, a combined small RNA and transcriptome sequencing analysis was performed on floral buds at the meiosis stage in three-line hybrid cotton system, and differentially expressed microRNAs (DEMs) and their target genes were identified and further analyzed for a possible involvement in CMS and fertility restoration. Totally 10 and 30 differentially expressed miRNA-target gene pairs were identified in A-B and A-R comparison group, respectively. A putative regulatory network of CMS occurrence and fertility restoration-related miRNA-target pairs during anther development were then constructed. The RLM-RACE analysis showed that gra-miR7505b regulates a PPR gene (Gh_DO5G3392) by cleaving precisely at the 643 nt and 748 nt sites. The further analysis indicated that the sequence variation in the binding regions of Gh_D05G3392 and Gh_D05G3356 may cause a lower cleavage efficiency of the PPR genes by miR7505b and miR7505 in R line, respectively, leading to the up-regulation of the PPR genes and fertility restoration. These results have established their genetic involvement in fertility restoration in the CMS-D2 system.
Conclusion: Our combined miRNA and transcriptome analysis in three-line hybrid cotton system provides new insights into the molecular mechanisms of CMS occurrence and fertility restoration, which will contribute to further hybrid breeding in cotton.

• 出版日期2018-10-17
• 单位中国农业科学院