State Key Laboratory of Agricultural Microbiology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
The State Key Laboratory of Plant Cell & Chromosome Engineering, Center for Agricultural Research Resources, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 286 Huaizhong Road, Shijiazhuang 050021, China.
Int J Mol Sci. 2020 Jan 27;21(3):819. doi: 10.3390/ijms21030819.
DELLA (GAI/RGA/RGL1/RGL2/RGL3) proteins are key negative regulators in GA (gibberellin) signaling and are involved in regulating plant growth as a response to environmental stresses. It has been shown that the DELLA protein PROCERA (PRO) in tomato promotes drought tolerance, but its molecular mechanism remains unknown. Here, we showed that the (gibberellin insensitive 1) mutant (generated from the - (L) allele (with a 17 amino acid deletion within the DELLA domain of GAI) by backcrossing - (L) with Col-0 three times), the gain-of-function mutant of GAI (GA INSENSITIVE) in , increases drought tolerance. The stomatal density of the mutant was increased but its stomatal aperture was decreased under abscisic acid (ABA) treatment conditions, suggesting that the drought tolerance of the mutant is a complex trait. We further tested the interactions between DELLA proteins and ABF2 (abscisic acid (ABA)-responsive element (ABRE)-binding transcription factors) and found that there was a strong interaction between DELLA proteins and ABF2. Our results provide new insight into DELLA proteins and their role in drought stress tolerance.
DELLA（GAI/RGA/RGL1/RGL2/RGL3）蛋白是 GA（赤霉素）信号转导的关键负调控因子，参与植物生长的调节以应对环境胁迫。已经表明，番茄中的 DELLA 蛋白 PROCERA（PRO）促进耐旱性，但它的分子机制尚不清楚。在这里，我们表明 （gibberellin insensitive 1）突变体（通过与 Col-0 回交三次，由 -（L）等位基因（在 GAI 的 DELLA 结构域内缺失 17 个氨基酸）产生），在 中的 GAI 的功能获得性突变体（GA INSENSITIVE）增加耐旱性。在脱落酸（ABA）处理条件下，突变体的气孔密度增加，但气孔孔径减小，表明突变体的耐旱性是一种复杂的性状。我们进一步测试了 DELLA 蛋白与 ABF2（脱落酸（ABA）响应元件（ABRE）结合转录因子）之间的相互作用，发现 DELLA 蛋白与 ABF2 之间存在很强的相互作用。我们的结果为 DELLA 蛋白及其在耐旱性中的作用提供了新的见解。
