Department of Plant and Soil Sciences, Mississippi State University, Mississippi State, MS, 39762, USA.
Irrigated Agriculture Research and Extension Center, Washington State University, Prosser, WA, 99350, USA.
Planta. 2018 Feb;247(2):369-379. doi: 10.1007/s00425-017-2784-7. Epub 2017 Oct 11.
Presented here is the first Echinochloa colona leaf transcriptome. Analysis of gene expression before and after herbicide treatment reveals that E. colona mounts a stress response upon exposure to herbicide. Herbicides are the most frequently used means of controlling weeds. For many herbicides, the target site is known; however, it is considerably less clear how plant gene expression changes in response to herbicide exposure. In this study, changes in gene expression in response to herbicide exposure in imazamox-sensitive (S) and- resistant (R) junglerice (Echinochloa colona L.) biotypes was examined. As no reference genome is available for this weed, a reference leaf transcriptome was generated. Messenger RNA was isolated from imazamox-treated- and untreated R and S plants and the resulting cDNA libraries were sequenced on an Illumina HiSeq2000. The transcriptome was assembled, annotated, and differential gene expression analysis was performed to identify transcripts that were upregulated or downregulated in response to herbicide exposure for both biotypes. Differentially expressed transcripts included transcription factors, protein-modifying enzymes, and enzymes involved in metabolism and signaling. A literature search revealed that members of the families represented in this analysis were known to be involved in abiotic stress response in other plants, suggesting that imazamox exposure induced a stress response. A time course study examining a subset of transcripts showed that expression peaked within 4-12 h and then returned to untreated levels within 48 h of exposure. Testing of plants from two additional biotypes showed a similar change in gene expression 4 h after herbicide exposure compared to the resistant and sensitive biotypes. This study shows that within 48 h junglerice mounts a stress response to imazamox exposure.
这里呈现的是第一个稗草叶片转录组。对施药前后基因表达的分析表明，稗草在接触除草剂后会产生应激反应。除草剂是控制杂草最常用的手段。对于许多除草剂来说，其靶标位点是已知的；然而，植物基因表达如何响应除草剂暴露的变化则要清楚得多。在这项研究中，研究了敏感（S）和抗性（R）野黍生物型在接触咪草烟后基因表达的变化。由于这种杂草没有参考基因组，因此生成了一个参考叶片转录组。从咪草烟处理和未处理的 R 和 S 植株中分离出信使 RNA，并在 Illumina HiSeq2000 上对所得 cDNA 文库进行测序。对转录组进行了组装、注释，并进行了差异基因表达分析，以鉴定两种生物型中因除草剂暴露而上调或下调的转录本。差异表达的转录本包括转录因子、蛋白修饰酶以及参与代谢和信号转导的酶。文献检索表明，该分析中所代表的家族成员已知在其他植物中参与非生物胁迫反应，这表明咪草烟暴露诱导了应激反应。对一组亚转录本的时间进程研究表明，表达在 4-12 小时内达到峰值，然后在暴露 48 小时内恢复到未处理水平。对来自另外两个生物型的植物进行测试表明，与抗性和敏感生物型相比，在接触除草剂后 4 小时，基因表达也发生了类似的变化。这项研究表明，在 48 小时内，稗草对咪草烟暴露会产生应激反应。
