Identification of microRNAs regulating grain filling of rice inferior spikelets in response to moderate soil drying post-anthesis
Identification of microRNAs regulating grain filling of rice inferior spikelets in response to moderate soil drying post-anthesis
复制标题
鉴定调节水稻劣质小穗籽粒灌浆响应花后适度土壤干燥的 microRNA
DOI：
10.1016/j.cj.2021.11.004
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发表时间：
2022-08-01
期刊：
影响因子：
6.6
通讯作者：
Ye，Nenghui
中科院分区：
文献类型：
--
作者：
Teng，Zhenning;Chen，Yinke;Ye，Nenghui
在大穗多穗品种中，劣势小穗的灌浆比优势小穗的灌浆更不完整，并受到花后土壤适度干燥的促进。越来越多的证据表明，microrna在调节谷物发育中起作用。然而，在MD胁迫下，microRNA调控劣势小穗灌浆的机制尚不清楚。本研究中，MD处理促进了Nipponbare弱势小穗灌浆。在对照（CK）和MD处理下，对弱势小穗灌浆最活跃期进行了小rna谱分析。在521种已知mirna和128种新型mirna中，38种已知mirna和9种新型mirna在CK和MD处理之间存在差异表达。差异表达mirna的靶基因参与多种发育和信号通路，与催化活性、碳水化合物代谢和其他功能相关。MD上调miR1861和miR397，导致SSIIIa活性和BR信号的负调节因子ossbdcp1和doslac的表达降低。相反，MD降低了miR1432的丰度，导致osacotp的上调，从而增加了ABA和IAA的含量。这些结果表明，在MD处理下，淀粉合成和植物激素的生物合成都受到下部小穗中差异表达的mirna的调控。研究结果揭示了mirna调控水稻弱粒灌浆的分子机制，为利用遗传方法提高水稻产量提供了潜在的应用前景。
The grain filling of inferior spikelets is much less complete than that of superior spikelets in rice cultivars with large panicles and numerous spikelets and is promoted by moderate soil drying (MD) post-anthesis. A growing body of evidence has shown that microRNAs function in regulating grain development. However, little is known about the mechanism of microRNA control of grain filling of inferior spikelets in response to MD. In this study, grain filling of inferior spikelets was promoted by MD treatment in Nipponbare. Small-RNA profiling at the most active grain-filling stage was conducted in inferior spikelets under control (CK) and MD treatment. Of 521 known and 128 novel miRNAs, 38 known and 9 novel miRNAs were differentially expressed between the CK and MD treatments. Target genes of differentially expressed miRNAs were involved in multiple developmental and signaling pathways associated with catalytic activity, carbohydrate metabolism, and other functions. Both miR1861 and miR397 were upregulated by MD, leading to a decrease inOsSBDCP1andOsLAC, two negative regulators of SSIIIa activity and BR signaling, respectively. In contrast, miR1432 abundance was reduced by MD, resulting in upregulation ofOsACOTand thus an elevated content of both ABA and IAA. These results suggest that both starch synthesis and phytohormone biosynthesis are regulated by differentially expressed miRNAs in inferior spikelets in response to MD treatment. Our results suggest the molecular mechanisms by which miRNAs regulate grain filling in inferior spikelets of rice under moderate soil drying, providing potential application in agriculture to increase rice yields by genetic approaches.