Amity Institute of Biotechnology, Amity University, Kolkata, India.
Department of Biochemistry and Biophysics, University of Kalyani, Kalyani, Nadia, India.
Comput Biol Chem. 2019 Oct;82:9-24. doi: 10.1016/j.compbiolchem.2019.06.005. Epub 2019 Jun 10.
LEA (Late Embryogenesis Abundant) proteins are abundant in plants and play a crucial role in abiotic stress tolerance. In our work, we primarily focused on the variations in physiochemical properties, conserved domains, secondary structure, gene ontology and evolutionary relationships among 40 LEA proteins of Triticum aestivum (common wheat). Wheat LEA protein belongs to first 6 classes out of the 13 classes present in LEApdB, the comprehensive database for LEA proteins. Proteins belonging to each LEApdB class have structures and functions distinguished from other classes. The study found three different conserved LEA domains in Triticum aestivum. One important domain was dehydrin, present in wheat proteins of classes 1, 2 and 4, though varied in sequence level, have similar biological processes. The study also found sequence level and phylogenetic similarity between dehydrin domains of class 1 and 4, but distinct from that of LEApdB class 2. This study also demonstrated functional diversity in two class 6 proteins occurred due to many destabilizing mutations in the LEA4 domain that caused alteration of ligand binding and conformational shift from 3-helix → turn within the domain. The LEA4 domains of these proteins also showed functional similarity and evolutionary relatedness with three other proteins of genus Aegilops, denoting that these proteins in Triticum aestivum were derived from its ancestor Aegilops. The study also assigned LEApdB class 4 to an unclassified LEA protein 'WZY2-1' based on amino acid composition, conserved domain, motif architecture and phylogenetic relatedness with class 4 proteins. Our study has revealed a detailed analysis of LEA proteins in Triticum aestivum and can serve as a pillar for further investigations and comparative analysis of wheat LEA proteins with other cereal or plant types.
LEA（晚期胚胎丰富）蛋白在植物中含量丰富，在非生物胁迫耐受中起着至关重要的作用。在我们的工作中，我们主要关注 40 种普通小麦（Triticum aestivum）LEA 蛋白的理化性质、保守结构域、二级结构、基因本体论和进化关系的变化。小麦 LEA 蛋白属于 LEApdB 数据库中 13 个 LEA 蛋白类别中的前 6 个类别，LEApdB 是 LEA 蛋白的综合数据库。属于每个 LEApdB 类别的蛋白质具有与其他类别不同的结构和功能。该研究在 Triticum aestivum 中发现了三个不同的保守 LEA 结构域。一个重要的结构域是脱水素，存在于小麦的 1、2 和 4 类蛋白中，尽管在序列水平上有所不同，但具有相似的生物学过程。该研究还发现 1 类和 4 类脱水素结构域在序列水平和系统发育上的相似性，但与 LEApdB 类 2 不同。这项研究还表明，由于 LEA4 结构域中存在许多不稳定突变，导致配体结合的改变和构象从结构域内的 3 螺旋→ 转弯的转变，导致 2 类中的两个 6 类蛋白发生了功能多样性。这些蛋白质的 LEA4 结构域也与属 Aegilops 的其他三种蛋白质具有功能相似性和进化相关性，这表明小麦中的这些蛋白质是从其祖先 Aegilops 衍生而来的。该研究还根据氨基酸组成、保守结构域、基序结构和与 4 类蛋白的系统发育关系，将 LEApdB 类 4 分配给一个未分类的 LEA 蛋白“WZY2-1”。我们的研究揭示了对普通小麦 LEA 蛋白的详细分析，可为进一步研究和比较小麦 LEA 蛋白与其他谷物或植物类型奠定基础。
