Shu Yongjun, Li Wei, Zhao Jinyue, Liu Ying, Guo Changhong
College of Life Science and Technology, Harbin Normal University, Harbin Heilongjiang, China.
Genet Mol Biol. 2018;41(3):638-648. doi: 10.1590/1678-4685-GMB-2017-0284. Epub 2018 Jun 28.
Medicago ruthenica is a perennial forage legume with the remarkable ability to survive under unfavorable environmental conditions. It has been identified as an excellent species of Medicago that can adapt to various environmental stresses including low temperature, drought, and salinity. To investigate its potential as a genetic resource, we performed transcriptome sequencing and analysis in M. ruthenica under abiotic stresses. We generated >120 million reads from six cDNA libraries, resulting in 79,249 unique transcripts, most of which were highly similar to transcripts from M. truncatula (44,608, 56.3%) and alfalfa (M. sativa, 48,023, 60.6%). Based on gene expression profiles, 2,721 transcripts were identified as abiotic stress responsive genes which were predicted to be mainly involved in phytohormone signaling pathways, transcriptional regulation, and ROS-scavenging. These results suggest that they play critical roles in the response to abiotic stress. In summary, we identified genes in our transcriptome dataset involved in the regulation of the abiotic stress response in M. ruthenica which will provide a valuable resource for the future identification and functional analysis of candidate genes for adaption to unfavorable conditions. The genes identified here could be also useful for improving stress tolerance traits in alfalfa through molecular breeding in the future.
扁蓿豆是一种多年生豆科牧草，具有在不利环境条件下生存的卓越能力。它已被确定为苜蓿属中的优良物种，能够适应包括低温、干旱和盐度在内的各种环境胁迫。为了研究其作为遗传资源的潜力，我们在非生物胁迫下对扁蓿豆进行了转录组测序和分析。我们从六个cDNA文库中获得了超过1.2亿条 reads，产生了79,249个独特转录本，其中大部分与蒺藜苜蓿（44,608个，56.3%）和紫花苜蓿（苜蓿，48,023个，60.6%）的转录本高度相似。基于基因表达谱，鉴定出2,721个转录本为非生物胁迫响应基因，预计这些基因主要参与植物激素信号通路、转录调控和活性氧清除。这些结果表明它们在对非生物胁迫的响应中起关键作用。总之，我们在转录组数据集中鉴定出了参与扁蓿豆非生物胁迫响应调控的基因，这将为未来鉴定和功能分析适应不利条件的候选基因提供宝贵资源。这里鉴定出的基因在未来通过分子育种提高苜蓿的胁迫耐受性性状方面也可能有用。
