Han Guoliang, Qiao Ziqi, Li Yuxia, Yang Zongran, Zhang Ziwei, Zhang Yuanyuan, Guo Jinjiao, Liu Lili, Wang Chengfeng, Wang Baoshan
Shandong Provincial Key Laboratory of Plant Stress Research, College of Life Sciences, Shandong Normal University, Shandong, China.
Front Plant Sci. 2022 Oct 26;13:1039984. doi: 10.3389/fpls.2022.1039984. eCollection 2022.
is a dicotyledonous recretohalophyte with several multicellular salt glands on the leaves. The plant can directly secrete excess salt onto the leaf surface through the salt glands to maintain ion homeostasis under salt stress. Therefore, it is of great significance to study the functions of genes related to salt gland development and salt tolerance. In this study, an R1-type MYB transcription factor gene was screened from , named , and its expression was strongly induced by salt stress. Subcellular localization analysis showed that was localized in the nucleus. LbMYB48 protein has transcriptional activation activity shown by transcriptional activation experiments. The density of salt glands in the leaves and the salt secretion capacity of -silenced lines were decremented, as demonstrated by the leaf disc method to detect sodium ion secretion. Furthermore, salt stress index experiments revealed that the ability of -silenced lines to resist salt stress was significantly reduced. regulates salt gland development and salt tolerance in mainly by regulating the expression of epidermal cell development related genes such as and and salt stress-related genes (, , and ) as demonstrated by RNA-seq analysis of LbMYB48-silenced lines. The heterologous over-expression of in improves salt tolerance of plants by stabilizing ion and osmotic balance and is likely to be involved in the abscisic acid signaling pathway. Therefore, , a transcriptional activator regulates the salt gland development of and salt tolerance of and
是一种双子叶泌盐盐生植物，叶片上有多个多细胞盐腺。该植物能够通过盐腺将多余盐分直接分泌到叶表面，以在盐胁迫下维持离子稳态。因此，研究与盐腺发育和耐盐性相关基因的功能具有重要意义。在本研究中，从 中筛选出一个R1型MYB转录因子基因，命名为 ，其表达受盐胁迫强烈诱导。亚细胞定位分析表明 定位于细胞核。转录激活实验表明LbMYB48蛋白具有转录激活活性。通过叶盘法检测钠离子分泌表明，沉默株系叶片中盐腺的密度和盐分分泌能力降低。此外，盐胁迫指数实验表明，沉默株系抵抗盐胁迫的能力显著降低。对沉默株系的RNA测序分析表明， 主要通过调控表皮细胞发育相关基因如 和 以及盐胁迫相关基因（ 、 和 ）的表达来调节 的盐腺发育和耐盐性。 在 中的异源过表达通过稳定离子和渗透平衡提高植物的耐盐性，并且可能参与脱落酸信号通路。因此，转录激活因子 调节 的盐腺发育和 的耐盐性，并且
