Expression Analysis of WRKY Transcription Factor Genes in Response to Abiotic Stresses in Horsegram (<i>Macrotyloma uniflorum</i> (Lam.) Verdc.)

Abstract

Drought and salt stress are two major environmental constraints that limit the productivity of agriculture crops worldwide. WRKY transcription factors are the plantspecific transcription factors that regulate several developmental events and stress responses in plants. The WRKY domain is defined by a 60-amino acid conserved sequence named WRKYGQK at N-terminal and a Zinc Finger-like motif at the Cterminal. WRKY genes are known to respond several stresses which may act as negative or positive regulators. The function of most of the WRKY transcription factors from non-model plants remains poorly understood. This investigation shows the expression levels of eight WRKY transcription factor genes from horsegram plant under drought and salt stress conditions. The increase in mRNA transcript levels of WRKY transcription factor genes was found to be high in drought stressed plants compared to salt-stressed plants. The levels of MDA which indicates the lipid peroxidation were less in drought stress. More ROS is produced in salt stress conditions compared to drought. The results show that the expression of WRKY transcription factors in drought stress conditions is reducing the adverse effect of stress on plants. These results also suggest that, during abiotic stress conditions such as drought and salt stress, WRKY transcription factors are regulated at the transcription level.

A Novel WRKY Transcription Factor, MuWRKY3 (Macrotyloma uniflorum Lam. Verdc.) Enhances Drought Stress Tolerance in Transgenic Groundnut (Arachis hypogaea L.) Plants

“…is well adapted to semi-arid conditions with higher drought tolerance ability. From, our previous study, the MuWRKY3 gene was found to be highly up-regulated among eight different WRKY genes studied ( Kiranmai et al, 2016 ). In this study, the full-length WRKY3 gene was successfully isolated from horsegram and designated as MuWRKY3 (GenBank Accession: KM520390.1).…”

Genome, Transcriptome, and Germplasm Sequencing Uncovers Functional Variation in the Warm-Season Grain Legume Horsegram Macrotyloma uniflorum (Lam.) Verdc.

“…A protein–protein homology search against a plant TFs database revealed that bHLH, ERF, C2H2, WRKY, and NAC transcription factors were abundant in the horsegram genome. These TFs confer tolerance of biotic and abiotic stresses in many crops including horsegram ( Nuruzzaman et al, 2013 ; Pandurangaiah et al, 2014 ; Kiranmai et al, 2016 , 2018 ; Sun et al, 2018 ; Han et al, 2020 ). The inherent drought tolerance mechanism of horsegram is most likely due to the presence of these TFs in its genome.…”

Untitled

“…It is mainly grown in Africa, Australia, Burma, India, Malaysia, Mauritius, and West Indies 1 . It is generally considered as protein-rich poor man's crop that grows well under dry conditions (low rainfall) and marginal soil fertility 5 . Since, it is also a rich source of protein, vitamins, and minerals; therefore it can contribute to fight against protein malnutrition in the developing world.…”

“…Therefore, to effectively eradicate the protein malnutrition, the underutilized legumes like horse gram have a great potential in the nutritional security of rural, tribal and underprivileged people 6 . The crop accounts for about 5-10% of pulses production in India and its annual production is about 0.65 million tones 5 . Since, horse gram has good nutritive potential, and it is fairly resistant to various abiotic and biotic stresses.…”