马蔺响应盐胁迫WRKY类基因鉴定及IlWRKY1功能解析

Iris lactea var. chinensis originated in China, is a perennial root herbaceous halophyte plant in the Iridaceae of Iris genus, and has good application prospect in the ecological construction for their strong root system and great ornamental value as well as heavy salt resistance. Previous studies have shown that IlWRKY1 gene was significantly differentially expressed under salt treatment, however, of how many WRKY genes from I. lactea var. chinensis involved in salt stress, especially the function and molecular mechanism of IlWRKY1 gene in response to salt stress are still unknown. In this study, we mine and identify WRKY genes in response to salt stress in I. lactea var. chinensis through transcriptome data analysis and establish the regulation networks of salt stress-response WRKY genes by gene co-expression analysis; At the same time, we cloned the salt stress-response IlWRKY1 genes as a breakthrough point to investigate the biological function and molecular mechanism of IlWRKY1 gene through biotechnology, yeast two hybrid technology, BiFC and so on. Those provide a basis for understanding the molecular mechanisms of IlWRKY genes in response to salt stress and utilizing the salt-tolerant genes with important application value in I. lactea var. chinensis.

马蔺（Iris lactea var. chinensis）原产于中国，是鸢尾科鸢尾属多年生宿根盐生草本植物，其根系发达、观赏价值高，耐重盐碱，在生态建设中有良好的应用前景。已有研究表明，马蔺响应盐胁迫IlWRKY1基因在盐胁迫下被显著差异表达，而关于马蔺有多少WRKY类基因响应盐胁迫，尤其IlWRKY1基因参与盐胁迫应答的功能和调控机制目前尚未报道。本研究通过对马蔺转录组数据分析，挖掘和鉴定马蔺响应盐胁迫WRKY类基因，并通过基因共表达分析，建立马蔺响应盐胁迫WRKY基因的调控网络；同时以克隆到的马蔺响应盐胁迫IlWRKY1基因为切入点，通过转基因技术、酵母双杂技术、BiFC等研究它在马蔺盐胁迫应答中的功能及调控机制。这将为理解马蔺WRKY基因应答盐胁迫分子机制和利用马蔺中具有重要应用价值的耐盐基因提供依据。

马蔺（Iris lactea var. chinensis）原产于中国，是鸢尾科鸢尾属多年生宿根盐生草本植物，其根系发达、观赏价值高，耐重盐碱，在生态建设中有良好的应用前景。已有研究表明，马蔺响应盐胁迫IlWRKY1基因在盐胁迫下被显著差异表达，而关于马蔺有多少WRKY类基因响应盐胁迫，尤其IlWRKY1基因参与盐胁迫应答的功能和调控机制目前尚未报道。本研究通过对马蔺转录组数据分析，挖掘和鉴定了64个马蔺WRKY基因，其中25个IlWRKY基因在马蔺叶片中受盐胁迫诱导差异表达；结合盐胁迫下马蔺响应盐胁迫IlWRKY基因的转录组数据和定量PCR数据，利用基因共表达分析策略，我们构建了一个涉及19个马蔺盐响应WRKY基因的共表达网络，并确定7个IlWRKY基因（IlWRKY1、IlWRKY5、IlWRKY3、IlWRKY4、IlWRKY6、IlWRKY18和IlWRKY2）为马蔺响应盐胁迫WRKY类候选基因；进一步克隆和鉴定了5个马蔺响应盐胁迫WRKY基因（IlWRKY1、IlWRKY2、IlWRKY3、IlWRKY4和IlWRKY5）全长序列，构建马蔺lWRKY1和lWRKY2基因过表达载体，进行转化拟南芥，获得转基因植株，初步发现高度同源的IlWRKY1基因和IlWRKY2基因有功能分歧，过表达IlWRKY1基因植株能增在盐胁迫下的耐性，而过表达IlWRKY2能够增加盐胁迫对拟南芥根系生长的抑制程度，表明马蔺IlWRKY2转录因子可能作为一个负调控因子参与盐胁迫响应过程。这些为揭示马蔺WRKY基因响应盐胁迫的分子机制和利用马蔺中具有重要应用价值的耐盐基因提供依据。项目按照计划进行，完成了各项考核指标。项目执行期间发表标注项目批准号的SCI论文5篇，其中JCR影响因子大于3的SCI论文3篇，申请国家发明专利2项。