Huang Xianzhong, Yang Lifei, Jin Yuhuan, Lin Jun, Liu Fang
Special Plant Genomics Laboratory, College of Life Sciences, Shihezi UniversityShihezi, China.
Front Plant Sci. 2017 Jun 7;8:955. doi: 10.3389/fpls.2017.00955. eCollection 2017.
is an ephemeral plant, and a close relative of the model plant , but it possesses higher photosynthetic efficiency, higher propagation rate, and higher salinity tolerance compared to those , thus providing a candidate plant system for gene mining for environmental adaption and salt tolerance. However, is an under-explored resource for understanding the genetic mechanisms underlying abiotic stress adaptation. To improve our understanding of the molecular and genetic mechanisms of salt stress adaptation, more than 19,900 clones randomly selected from a cDNA library constructed previously from leaf tissue exposed to high-salinity shock were sequenced. A total of 16,014 high-quality expressed sequence tags (ESTs) were generated, which have been deposited in the dbEST GenBank under accession numbers JZ932319 to JZ948332. Clustering and assembly of these ESTs resulted in the identification of 8,835 unique sequences, consisting of 2,469 contigs and 6,366 singletons. The blastx results revealed 8,011 unigenes with significant similarity to known genes, while only 425 unigenes remained uncharacterized. Functional classification demonstrated an abundance of unigenes involved in binding, catalytic, structural or transporter activities, and in pathways of energy, carbohydrate, amino acid, or lipid metabolism. At least seven main classes of genes were related to salt-tolerance among the 8,835 unigenes. Many previously reported salt tolerance genes were also manifested in this library, for example . In addition, 251 transcription factors were identified from the library, classified into 42 families. Lastly, changes in expression of the 12 most abundant unigenes, 12 transcription factor genes, and 19 stress-related genes in the first 24 h of exposure to high-salinity stress conditions were monitored by qRT-PCR. The large-scale EST library obtained in this study provides first-hand information on gene sequences expressed in young leaves of exposed to salt shock. The rapid discovery of known or unknown genes related to salinity stress response in will facilitate the understanding of complex adaptive mechanisms for ephemerals.
是一种一年生植物，也是模式植物的近缘种，但与模式植物相比，它具有更高的光合效率、更高的繁殖率和更高的耐盐性，因此为环境适应性和耐盐性基因挖掘提供了一个候选植物系统。然而，在理解非生物胁迫适应的遗传机制方面，它是一个尚未充分探索的资源。为了增进我们对盐胁迫适应的分子和遗传机制的理解，从先前构建的、来自遭受高盐冲击的叶片组织的cDNA文库中随机选择了超过19900个克隆进行测序。总共产生了16014个高质量的表达序列标签（EST），这些EST已存入dbEST GenBank，登录号为JZ932319至JZ948332。对这些EST进行聚类和组装后，鉴定出8835个独特序列，包括2469个重叠群和6366个单拷贝序列。blastx结果显示，有8011个单基因与已知基因具有显著相似性，而只有425个单基因未被表征。功能分类表明，大量单基因参与结合、催化、结构或转运活性，以及能量、碳水化合物、氨基酸或脂质代谢途径。在这8835个单基因中，至少有七大类基因与耐盐性有关。许多先前报道的耐盐基因在该文库中也有体现，例如 。此外，从该文库中鉴定出251个转录因子，分为42个家族。最后，通过qRT-PCR监测了在高盐胁迫条件下暴露的前24小时内，12个最丰富的单基因、12个转录因子基因和19个胁迫相关基因的表达变化。本研究获得的大规模EST文库提供了关于遭受盐冲击的 幼叶中表达的基因序列的第一手信息。快速发现与 盐胁迫反应相关的已知或未知基因将有助于理解一年生植物复杂的适应机制。
