Integrative Agriculture Department, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al Ain 15551, United Arab Emirates.
Department of Vegetable Science, College of Agriculture, Kerala Agricultural University, Thrissur 680656, India.
Biomolecules. 2021 Nov 9;11(11):1662. doi: 10.3390/biom11111662.
In response to various environmental stresses, plants have evolved a wide range of defense mechanisms, resulting in the overexpression of a series of stress-responsive genes. Among them, there is certain set of genes that encode for intrinsically disordered proteins (IDPs) that repair and protect the plants from damage caused by environmental stresses. Group II LEA (late embryogenesis abundant) proteins compose the most abundant and characterized group of IDPs; they accumulate in the late stages of seed development and are expressed in response to dehydration, salinity, low temperature, or abscisic acid (ABA) treatment. The physiological and biochemical characterization of group II LEA proteins has been carried out in a number of investigations because of their vital roles in protecting the integrity of biomolecules by preventing the crystallization of cellular components prior to multiple stresses. This review describes the distribution, structural architecture, and genomic diversification of group II LEA proteins, with some recent investigations on their regulation and molecular expression under various abiotic stresses. Novel aspects of group II LEA proteins in and in orthodox seeds are also presented. Genome-wide association studies (GWAS) indicated a ubiquitous distribution and expression of group II LEA genes in different plant cells. In vitro experimental evidence from biochemical assays has suggested that group II LEA proteins perform heterogenous functions in response to extreme stresses. Various investigations have indicated the participation of group II LEA proteins in the plant stress tolerance mechanism, spotlighting the molecular aspects of group II LEA genes and their potential role in biotechnological strategies to increase plants' survival in adverse environments.
针对各种环境压力，植物已经进化出了广泛的防御机制，导致一系列应激响应基因的过度表达。其中，有一组特定的基因编码内在无序蛋白（IDP），这些蛋白可以修复和保护植物免受环境压力造成的损伤。第 II 组 LEA（晚期胚胎丰富）蛋白是最丰富和最具特征的 IDP 组之一；它们在种子发育的晚期积累，并在响应脱水、盐度、低温或脱落酸（ABA）处理时表达。由于它们在防止细胞成分在多种压力下结晶之前保护生物分子的完整性方面起着至关重要的作用，因此对第 II 组 LEA 蛋白的生理生化特性进行了许多研究。本综述描述了第 II 组 LEA 蛋白的分布、结构架构和基因组多样化，以及最近对它们在各种非生物胁迫下的调控和分子表达的一些研究。还介绍了第 II 组 LEA 蛋白在和正种子中的新方面。全基因组关联研究（GWAS）表明，第 II 组 LEA 基因在不同植物细胞中广泛分布和表达。来自生化分析的体外实验证据表明，第 II 组 LEA 蛋白在应对极端压力时具有异构功能。各种研究表明，第 II 组 LEA 蛋白参与植物应激耐受机制，强调了第 II 组 LEA 基因的分子方面及其在生物技术策略中提高植物在不利环境中生存能力的潜在作用。
