Li Yue, Wan Liqiang, Bi Shuyi, Wan Xiufu, Li Zhenyi, Cao Jing, Tong Zongyong, Xu Hongyu, He Feng, Li Xianglin
Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China.
Genes (Basel). 2017 Apr 13;8(4):119. doi: 10.3390/genes8040119.
Alfalfa, an important forage legume, is an ideal crop for sustainable agriculture and a potential crop for bioenergy resources. Drought, one of the most common environmental stresses, substantially affects plant growth, development, and productivity. MicroRNAs (miRNAs) are newly discovered gene expression regulators that have been linked to several plant stress responses. To elucidate the role of miRNAs in drought stress regulation of alfalfa, a high-throughput sequencing approach was used to analyze 12 small RNA libraries comprising of four samples, each with three biological replicates. From the 12 libraries, we identified 348 known miRNAs belonging to 80 miRNA families, and 281 novel miRNAs, using Mireap software. Eighteen known miRNAs in roots and 12 known miRNAs in leaves were screened as drought-responsive miRNAs. With the exception of miR319d and miR157a which were upregulated under drought stress, the expression pattern of drought-responsive miRNAs was different between roots and leaves in alfalfa. This is the first study that has identified miR3512, miR3630, miR5213, miR5294, miR5368 and miR6173 as drought-responsive miRNAs. Target transcripts of drought-responsive miRNAs were computationally predicted. All 447 target genes for the known miRNAs were predicted using an online tool. This study provides a significant insight on understanding drought-responsive mechanisms of alfalfa.
紫花苜蓿是一种重要的豆科牧草，是可持续农业的理想作物和生物能源资源的潜在作物。干旱是最常见的环境胁迫之一，严重影响植物的生长、发育和生产力。微小RNA（miRNA）是新发现的基因表达调节因子，与多种植物胁迫反应有关。为了阐明miRNA在紫花苜蓿干旱胁迫调节中的作用，采用高通量测序方法分析了12个小RNA文库，这些文库由四个样本组成，每个样本有三个生物学重复。利用Mireap软件，从这12个文库中，我们鉴定出了属于80个miRNA家族的348个已知miRNA和281个新的miRNA。筛选出根部的18个已知miRNA和叶片中的12个已知miRNA作为干旱响应miRNA。除了在干旱胁迫下上调的miR319d和miR157a外，紫花苜蓿根部和叶片中干旱响应miRNA的表达模式不同。这是首次将miR3512、miR3630、miR5213、miR5294、miR5368和miR6173鉴定为干旱响应miRNA的研究。通过计算预测了干旱响应miRNA的靶转录本。使用在线工具预测了已知miRNA的所有447个靶基因。本研究为理解紫花苜蓿的干旱响应机制提供了重要的见解。
