Dabravolski Siarhei A, Isayenkov Stanislav V
Department of Biotechnology Engineering, Braude Academic College of Engineering, Snunit 51, Karmiel 2161002, Israel.
Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, Betty-Heimann-Strasse 3, 06120 Halle, Germany.
Plants (Basel). 2025 Apr 28;14(9):1327. doi: 10.3390/plants14091327.
Expansins are cell wall-modifying proteins that play a pivotal role in plant growth, development, and stress adaptation to abiotic stress. This manuscript explores the functions of expansins in salt and drought stress responses across multiple plant species, highlighting their involvement in cell wall loosening, transcriptional regulation, ion and osmotic homeostasis, and phytohormone signalling. Genome-wide identification and expression analyses revealed differential regulation of expansin genes under abiotic stress conditions. In , overexpression of and promoted root elongation and ion homeostasis, improving salt and drought tolerance. Similarly, was found to modulate root architecture and phytohormone-mediated stress responses. In , was linked to cation exchange and auxin signalling under salt stress conditions. Conversely, in , exhibited a negative regulatory role in salt stress tolerance, highlighting species-specific differences in expansin function. Expansins also contribute to reactive oxygen species (ROS) homeostasis, as observed in transgenic plants with increased activities of SOD, POD, APX, and CAT, which reduced oxidative damage under stress. Additionally, enhanced accumulation of soluble sugars and proline in expansin-overexpressing plants suggests their involvement in osmotic adjustment mechanisms. The interplay between expansins and ABA, auxins, and ethylene further underscores their role in integrating mechanical and hormonal stress responses. Despite substantial progress, limitations remain in understanding the broader regulatory networks influenced by expansins. Future research should focus on elucidating their downstream molecular targets, transcriptional interactions, and functional diversity across different plant species. Expansins represent promising candidates for improving crop resilience to environmental stress, making them valuable targets for future breeding and biotechnological approaches.
扩展蛋白是细胞壁修饰蛋白，在植物生长、发育以及对非生物胁迫的应激适应中发挥关键作用。本论文探讨了扩展蛋白在多种植物物种应对盐胁迫和干旱胁迫中的功能，强调了它们在细胞壁松弛、转录调控、离子和渗透稳态以及植物激素信号传导中的作用。全基因组鉴定和表达分析揭示了非生物胁迫条件下扩展蛋白基因的差异调控。在[具体物种1]中，[基因1]和[基因2]的过表达促进了根的伸长和离子稳态，提高了对盐胁迫和干旱胁迫的耐受性。同样，[基因3]被发现可调节根系结构和植物激素介导的应激反应。在[具体物种2]中，[基因4]与盐胁迫条件下的阳离子交换和生长素信号传导有关。相反，在[具体物种3]中，[基因5]在盐胁迫耐受性中表现出负调控作用，突出了扩展蛋白功能的物种特异性差异。扩展蛋白还对活性氧（ROS）稳态有贡献，如在超氧化物歧化酶（SOD）、过氧化物酶（POD）、抗坏血酸过氧化物酶（APX）和过氧化氢酶（CAT）活性增加的转基因植物中观察到的那样，这减少了胁迫下的氧化损伤。此外，扩展蛋白过表达植物中可溶性糖和脯氨酸的积累增加，表明它们参与渗透调节机制。扩展蛋白与脱落酸（ABA）、生长素和乙烯之间的相互作用进一步强调了它们在整合机械胁迫和激素应激反应中的作用。尽管取得了重大进展，但在理解受扩展蛋白影响的更广泛调控网络方面仍存在局限性。未来的研究应侧重于阐明它们的下游分子靶点、转录相互作用以及不同植物物种间的功能多样性。扩展蛋白是提高作物对环境胁迫抗性的有前景的候选者，使其成为未来育种和生物技术方法的有价值靶点。
