AUTHOR=Singh Chandra Mohan , Kumar Mukul , Pratap Aditya , Tripathi Anupam , Singh Smita , Mishra Anuj , Kumar Hitesh , Nair Ramkrishnan M. , Singh Narendra Pratap 

TITLE=Genome-Wide Analysis of Late Embryogenesis Abundant Protein Gene Family in Vigna Species and Expression of VrLEA Encoding Genes in Vigna glabrescens Reveal Its Role in Heat Tolerance

JOURNAL=Frontiers in Plant Science

VOLUME=Volume 13 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.843107

DOI=10.3389/fpls.2022.843107

ISSN=1664-462X

ABSTRACT=<p>Late embryogenesis abundant (LEA) proteins are identified in many crops for their response and role in adaptation to various abiotic stresses, such as drought, salinity, and temperature. The <italic>LEA</italic> genes have been studied systematically in several crops but not in <italic>Vigna</italic> crops. In this study, we reported the first comprehensive analysis of the <italic>LEA</italic> gene family in three legume species, namely, mung bean (<italic>Vigna radiata</italic>), adzuki bean (<italic>Vigna angularis</italic>), and cowpea (<italic>Vigna unguiculata</italic>), and the cross-species expression of <italic>VrLEA</italic> genes in a wild tetraploid species, <italic>Vigna glabrescens</italic>. A total of 201 <italic>LEA</italic> genes from three <italic>Vigna</italic> crops were identified harboring the LEA conserved motif. Among these 55, 64, and 82 <italic>LEA</italic> genes were identified in mung bean, adzuki bean, and cowpea genomes, respectively. These <italic>LEA</italic> genes were grouped into eight different classes. Our analysis revealed that the cowpea genome comprised all eight classes of <italic>LEA</italic> genes, whereas the LEA-6 class was absent in the mung bean genome. Similarly, LEA-5 and LEA-6 were absent in the adzuki bean genome. The analysis of <italic>LEA</italic> genes provides an insight into their structural and functional diversity in the <italic>Vigna</italic> genome. The genes, such as <italic>VrLEA-2</italic>, <italic>VrLEA-40</italic>, <italic>VrLEA-47</italic>, and <italic>VrLEA-55</italic>, were significantly upregulated in the heat-tolerant genotype under stress conditions indicating the basis of heat tolerance. The successful amplification and expression of <italic>VrLEA</italic> genes in <italic>V. glabrescens</italic> indicated the utility of the developed markers in mung bean improvement. The results of this study increase our understanding of <italic>LEA</italic> genes and provide robust candidate genes for future functional investigations and a basis for improving heat stress tolerance in <italic>Vigna</italic> crops.</p>