Zhengzhou Research Base, National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China.
Zhengzhou Research Base, National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; State Key Laboratory of Plant Genomics, Institute of Microbiology Research, Chinese Academy of Sciences, Beijing 100101, China.
Int J Biol Macromol. 2024 Oct;278(Pt 3):134857. doi: 10.1016/j.ijbiomac.2024.134857. Epub 2024 Aug 19.
Soil salinity is a major environmental constraint to plant production. The homeodomain-leucine zipper I (HD-Zip I) transcription factors play a crucial role in growth, development and defence responses of plants. However, the function and underlying mechanism of HD-Zip I in cotton remain unexplored. This study investigated the role of GhHB4-like, a cotton HD-Zip I gene, in plant tolerance to salt stress. Ectopic expression of GhHB4-like gene enhanced, while its silencing impaired the salt tolerance in Arabidopsis. Y1H and effector-reporter assays revealed that GhHB4-like activated the expression of GhNAC007, which is essential for salt resistance. Knock-down of GhNAC007 also impaired salt resistance of cotton plants. In addition, GhHB4-like-GhNAC007 might have positively regulated the expression of GhMYB96 and ABA signalling-related genes, thereby leading to enhanced salt resistance. Interestingly, deleting motifs 3 and 5 near the 3'-end of GhHB4-like significantly enhanced GhNAC007 activation, indicating that both motifs acted as transcriptional activation inhibitory domains. The results suggest that GhHB4-like-GhNAC007 regulated plant response to salt stress, potentially by modulating GhMYB96 and ABA signalling-related genes.
土壤盐度是植物生产的主要环境限制因素。同源域亮氨酸拉链 I（HD-Zip I）转录因子在植物的生长、发育和防御反应中起着至关重要的作用。然而，HD-Zip I 在棉花中的功能和作用机制仍未被探索。本研究调查了棉花 HD-Zip I 基因 GhHB4-like 在植物耐盐性中的作用。GhHB4-like 基因的异位表达增强了拟南芥的耐盐性，而其沉默则削弱了拟南芥的耐盐性。Y1H 和效应物报告基因检测表明，GhHB4-like 激活了 GhNAC007 的表达，GhNAC007 对盐胁迫至关重要。GhNAC007 的敲低也削弱了棉花植株的耐盐性。此外，GhHB4-like-GhNAC007 可能正向调控 GhMYB96 和 ABA 信号相关基因的表达，从而增强耐盐性。有趣的是，删除 GhHB4-like 3'-端附近的模体 3 和 5 显著增强了 GhNAC007 的激活，表明这两个模体都充当转录激活抑制结构域。结果表明，GhHB4-like-GhNAC007 调节植物对盐胁迫的反应，可能通过调节 GhMYB96 和 ABA 信号相关基因。
