背景:甘蓝型油菜是世界上第三大食用油来源。遗传雄性不育(GMS)品系为利用油菜杂种优势提供了关键材料。GMS系已成功用于我国油菜杂交生产。MicroRNAs(miRNAs)在各种植物生长中起着至关重要的调节作用,发展,和应激反应过程。然而,关于调节甘蓝型油菜GMS品系花粉发育的miRNA的报道很少。
结果:在这项研究中,构建了12个小RNA和转录组文库,并对两个隐性GMS(RGMS)系的可育和不育系的花蕾进行了测序,即,\"6251AB\"和\"6284AB\"。同时,还构建了12个小RNA和转录组文库,并对来自两个优势GMS(DGMS)系的可育和不育系的花蕾进行了测序,即,\"4001AB\"和\"4006AB\"。根据结果,46种已知的miRNA,已知前miRNA的另一个臂上的27个新miRNA,并鉴定了44个新的保守miRNA。发现了35对新的miRNA-3p/miRNA-5p。在所有鉴定的miRNA中,鉴定了15个差异表达的miRNA,在不育系和可育系的花蕾之间变化超过1.5倍,包括“4001A”和“4001B”之间的六个差异表达的miRNA,“4006A”和“4006B”之间的两个差异表达miRNA,“6251A”和“6251B”之间的四个差异表达miRNA,和“6284A”和“6284B”之间的十个差异表达的miRNA。进行小RNA与转录组测序的相关性分析。对15个差异表达的miRNA进行了257个候选靶基因的预测。5'修改RACE的结果表明,BnaA09g48720D,BnaA09g11120D,和BnaCnng51960D被bna-miR398a-3p切割,bna-miR158-3p和bna-miR159a,分别。在差异表达的miRNA中,选择miR159来分析其功能。在拟南芥中bna-miR159的过表达导致结实率降低,缩短角果,说明miR159可以调节油菜的育性和角果发育。
结论:我们的发现提供了可能参与GMS和花粉发育的miRNA的概述。提供了有关miRNA及其相关靶基因的新信息,以利用GMS机制并揭示欧洲油菜中的miRNA网络。
BACKGROUND: Brassica napus is the third leading source of edible oil in the world. Genic male sterility (GMS) lines provide crucial material for harnessing heterosis for rapeseed. GMS lines have been used successfully for rapeseed hybrid production in China. MicroRNAs (miRNAs) play crucial regulatory roles in various plant growth, development, and stress response processes. However, reports on miRNAs that regulate the pollen development of GMS lines in B. napus are few.
RESULTS: In this study, 12 small RNA and transcriptome libraries were constructed and sequenced for the flower buds from the fertile and sterile lines of two recessive GMS (RGMS) lines, namely, \"6251AB\" and \"6284AB\". At the same time, 12 small RNA and transcriptome libraries were also constructed and sequenced for the flower buds from the fertile and sterile lines of two dominant GMS (DGMS) lines, namely, \"4001AB\" and \"4006AB\". Based on the results, 46 known miRNAs, 27 novel miRNAs on the other arm of known pre-miRNAs, and 44 new conserved miRNAs were identified. Thirty-five pairs of novel miRNA-3p/miRNA-5p were found. Among all the identified miRNAs, fifteen differentially expressed miRNAs with over 1.5-fold change between flower buds of sterile and fertile lines were identified, including six differentially expressed miRNAs between \"4001A\" and \"4001B\", two differentially expressed miRNAs between \"4006A\" and \"4006B\", four differentially expressed miRNAs between \"6251A\" and \"6251B\", and ten differentially expressed miRNAs between \"6284A\" and \"6284B\". The correlation analysis of small RNA and transcriptome sequencing was conducted. And 257 candidate target genes were predicted for the 15 differentially expressed miRNAs. The results of 5\' modified RACE indicated that BnaA09g48720D, BnaA09g11120D, and BnaCnng51960D were cleaved by bna-miR398a-3p, bna-miR158-3p and bna-miR159a, respectively. Among the differentially expressed miRNAs, miR159 was chosen to analyze its function. Overexpression of bna-miR159 in Arabidopsis resulted in decreased seed setting rate, and shortened siliques, illustrating that miR159 may regulate the fertility and silique development in rapeseed.
CONCLUSIONS: Our findings provide an overview of miRNAs that are potentially involved in GMS and pollen development. New information on miRNAs and their related target genes are provided to exploit the GMS mechanism and reveal the miRNA networks in B. napus.