Huang Zhuo, Song Li, Xiao Yao, Zhong Xiaojuan, Wang Jiatong, Xu Wenxin, Jiang Cai-Zhong
College of Landscape Architecture, Sichuan Agricultural University, Chengdu, China.
Department of Plant Sciences, University of California, Davis, Davis, CA, United States.
Front Plant Sci. 2022 Jul 22;13:967352. doi: 10.3389/fpls.2022.967352. eCollection 2022.
Myrothamnus flabellifolia is the only woody resurrection plant discovered so far and could recover from extreme desiccation condition. However, few genes related to its strong drought tolerance have been characterized, and the underlying molecular mechanisms remains mysterious. Members of WRKY transcription factor family are effective in regulating abiotic stress responses or tolerance in various plants. An early dehydration-induced gene encoding a WRKY transcription factor namely MfWRKY41 was isolated from , which is homologous to AtWRKY41 of Arabidopsis. It contains a typical WRKY domain and zinc finger motif, and is located in the nucleus. Comparing to wild type, the four transgenic lines overexpressing showed better growth performance under drought and salt treatments, and exhibited higher chlorophyll content, lower water loss rate and stomatal aperture and better osmotic adjustment capacity. These results indicated that MfWRKY41 of positively regulates drought as well as salinity responses. Interestingly, the root system architecture, including lateral root number and primary root length, of the transgenic lines was enhanced by MfWRKY41 under both normal and stressful conditions, and the antioxidation ability was also significantly improved. Therefore, MfWRKY41 may have potential application values in genetic improvement of plant tolerance to drought and salinity stresses. The molecular mechanism involving in the regulatory roles of MfWRKY41 is worthy being explored in the future.
扇叶树萝卜是迄今为止发现的唯一一种木质化复苏植物，能够从极端干旱状态中恢复过来。然而，与其强大的耐旱性相关的基因鲜有被鉴定出来，其潜在的分子机制仍然成谜。WRKY转录因子家族成员在调控多种植物的非生物胁迫响应或耐受性方面发挥着作用。从[具体来源]中分离出一个早期脱水诱导的编码WRKY转录因子的基因，即MfWRKY41，它与拟南芥的AtWRKY41同源。它含有一个典型的WRKY结构域和锌指基序，并且定位于细胞核中。与野生型相比，过表达[MfWRKY41]的四个转基因株系在干旱和盐处理下表现出更好的生长性能，叶绿素含量更高，失水率和气孔孔径更低，渗透调节能力更强。这些结果表明，[扇叶树萝卜的]MfWRKY41正向调控干旱和盐胁迫响应。有趣的是，在正常和胁迫条件下，MfWRKY41均增强了转基因株系的根系结构，包括侧根数和主根长度，并且抗氧化能力也显著提高。因此，MfWRKY41在植物耐旱和耐盐胁迫的遗传改良方面可能具有潜在的应用价值。未来，涉及MfWRKY41调控作用的分子机制值得深入探究。
