Small RNA and Degradome Analyses Uncovering the Extensive Effects of miRNAs and Targets in Early Developing Grains of Common Wheat [post]

Qiaoyan Chen, Lina Xu, Yuanyuan Guan, Zeeshan Ali Buttar, Gan Li, Guang Zhang, Chunxiao Li, Jinyong Huang, Mingjiu Liu, Wenhui Wei
2020 unpublished
Background: The development of grains is important for wheat production, and wheat (Triticum aestivum) is one of the staple food crops worldwide. MicroRNAs (miRNAs), as a kind of small regulatory RNAs, play important roles during plant growth and development. Although the development of plant grain/seed is widely researched, there is limited knowledge on miRNAs's regulation of early developing wheat grains. Results: In the present study, miRNAs and their targets were explored in early
more » ... grains of wheat cultivar "Bainong 4199" at 7DAP and 14 DAP using high-throughput small RNA and degradome sequencing. A total of 105 known and 79 novel miRNAs were identified, including 46 known and 32 novel miRNAs from 7 DAP library and 87 known and 78 novel miRNAs from 14 DAP library, respectively. Expression analysis of miRNAs revealed that 39 miRNAs including 19 known and 20 novel miRNAs were differentially expressed between 7 DAP and 14 DAP. In total, 266 targets for 40 known wheat miRNAs, 152 targets for 13 other known plant miRNAs and 258 targets for 25 novel miRNAs were predicted across small RNA and degradome analyses. For differentially expressed miRNAs, 23 targets were predicted to be cleaved by 7 miRNAs, including 3 known and 4 novel miRNAs. Majority of the miRNAs potentially regulated multiple targets, whereas some miRNAs only acted on a single target gene. Functional analyses showed that miRNAs and their targets widely participated in the regulations of early wheat grain development and metabolism. The expression patterns of the randomly selected miRNAs and targets were validated using quantitative real-time polymerase chain reaction, and showed consistent and reliable results. Conclusion: This study suggests that quite a few known and novel miRNAs and their targets play extensive roles during the early grain development of common wheat. Understanding of miRNA-mediated regulatory network involved in wheat grain development will help us to elucidate the molecular mechanisms underlying wheat grain development and carry out ingenious molecular improvements in wheat breeding.
doi:10.21203/rs.3.rs-123517/v1 fatcat:cs2lij2ozzbmzd5zgils4ilokq