In Brassica napus L. (rapeseed), complete genic male sterility (GMS) plays an important role in the utilization of heterosis. Although microRNAs (miRNAs) play essential regulatory roles during bud development, knowledge of how GMS is regulated by miRNAs in rapeseed is rather limited. In this study, we obtained a novel recessive GMS system, CN12AB. The sterile line CN12A has defects in tapetal differentiation and degradation. Illumina sequencing was employed to examine the expression of miRNAs in the buds of CN12A and the fertile line CN12B. We identified 85 known miRNAs and 120 novel miRNAs that were expressed during rapeseed anther development. When comparing the expression levels of miRNAs between CN12A and CN12B, 19 and 18 known miRNAs were found to be differentially expressed in 0.5–1.0 mm buds and in 2.5–3.0 mm buds, respectively. Among these, the expression levels of 14 miRNAs were higher and the levels of 23 miRNAs were lower in CN12A compared with CN12B. The predicted target genes of these differentially expressed miRNAs encode protein kinases, F-box domain-containing proteins, MADS-box family proteins, SBP-box gene family members, HD-ZIP proteins, floral homeotic protein APETALA 2 (AP2), and nuclear factor Y, subunit A. These targets have previously been reported to be involved in pollen development and male sterility, suggesting that miRNAs might act as regulators of GMS in rapeseed anthers. Furthermore, RT-qPCR data suggest that one of the differentially expressed miRNAs, bna-miR159, plays a role in tapetal differentiation by regulating the expression of transcription factor BnMYB101 and participates in tapetal degradation and influences callose degradation by manipulating the expression of BnA6. These findings contribute to our understanding of the roles of miRNAs during anther development and the occurrence of GMS in rapeseed.

在甘蓝型油菜L.（油菜），完全不育的雄性不育（GMS）在利用杂种优势中起着重要作用。尽管microRNA（miRNA）在芽发育过程中起着至关重要的调节作用，但是油菜籽中miRNA如何调控GMS的知识却非常有限。在这项研究中，我们获得了新型隐性GMS系统CN12AB。无菌线CN12A在绒毛分化和降解方面存在缺陷。使用Illumina测序来检查miRNA在CN12A和可育系CN12B的芽中的表达。我们鉴定了在油菜花药发育过程中表达的85种已知miRNA和120种新颖miRNA。比较CN12A和CN12B之间的miRNA表达水平时，发现19和18种已知的miRNA在0.5–1.0 mm芽和2.5–3.0 mm芽中差异表达。在这些当中，与CN12B相比，CN12A中14种miRNA的表达水平较高，而23种miRNA的水平较低。这些差异表达的miRNA的预测靶基因编码蛋白激酶，包含F-box域的蛋白，MADS-box家族蛋白，SBP-box基因家族成员，HD-ZIP蛋白，花同源蛋白APETALA 2（AP2）和核这些靶点与花粉发育和雄性不育有关，这表明miRNA可能充当油菜花药中GMS的调节剂。此外，RT-qPCR数据表明，差异表达的miRNA之一，bna-miR159，通过调节转录因子BnMYB101的表达在绒毛分化中发挥作用，并参与绒毛降解并通过操纵BnA6的表达影响call的降解。这些发现有助于我们了解miRNA在花药发育过程中的作用以及油菜籽中GMS的发生。