大叶杨干旱和水淹胁迫的转录组分析

Transcriptomic Analysis of Populus lasiocarpa in Response to Drought and Waterlogging Stress

大叶杨(Populus lasiocarpa)是中国特有的杨属物种,干旱和水淹是影响大叶杨生长和分布范围的2个关键因子。AP2/ERF转录因子家族在植物响应非生物胁迫中发挥重要作用。研究采用转录组测序、生物信息学分析手段并结合分子实验验证初步鉴定了参与大叶杨干旱和水淹胁迫响应的关键基因。研究结果显示,(1)在大叶杨中分别鉴定到3986/385个响应干旱/水淹胁迫的差异表达基因,其中包括237个同时响应干旱和水淹胁迫的差异表达基因。(2)在大叶杨中共鉴定到205个AP2/ERF家族成员,系统发育分析表明其在大叶杨中主要分为5个亚家族,并显著富集于差异表达基因中。(3)筛选部分胁迫前后差异表达的PlAP2/ERF基因进行qRT-PCR实验,经证实这些基因在大叶杨受到干旱/水淹胁迫时均可被诱导表达。综上,大叶杨在水淹胁迫下的差异表达基因数量明显少于干旱胁迫,AP2/ERF基因家族的部分基因参与到大叶杨干旱/水淹胁迫的应激表达过程。

Populus lasiocarpa is a poplar species only locally distributed in China,and its growth and distribution range is seriously constrained by environmental factors such as drought and waterlogging.AP2/ERF transcription factor family plays important roles in response to abiotic stresses in plants.In this study,we integrated transcriptome sequencing,bioinformatics analysis and experimental validation to investigate genes that are likely to be involved in responses of drought and waterlogging stresses.The main results were presented as follows,(1)a total of 3986 and 385 differentially expressed genes(DEGs)were detected under drought and waterlogging conditions,respectively,of which 237 DEGs were shared under drought and waterlogging stresses.(2)A total of 205 AP2/ERF members were identified in P.lasiocarpa,which were clustered into five subfamilies and significantly enriched in DEGs.(3)Multiple PlAP2/ERF differentially expressed genes that are involved in the responses to drought and waterlogging stresses were further confirmed by qRT-PCR.In conclusion,the results showed that the number of DEGs under waterlogging stress were less than that under drought stress in P.lasiocarpa.PlAP2/ERF genes were highly involved in the process of abiotic stress responses.