Books & Book Chapters

Friday Seminar by Ms. Arunima Singh


Notice
 
Speaker : Arunima Singh
 
Topic      : WRKY Transcription factors act as a negative regulators of drought tolerance through ABA and BR mediated pathways
 
Date and Time : December 3, 2021 via. Online mode
 
All are cordially invited
 
 
Category: Education

WRKY Transcription factors act as negative regulators of drought tolerance through ABA and BR mediated pathways

Crop plants are increasingly being confronted with water deficient conditions due to global climate change, resulting in a reduction in crop productivity. Numerous studies have identified transcription factors (TFs) participating in drought tolerance mechanisms. WRKY TFs are one such family, which affect abiotic stress tolerance. OsWRKY5 is involved in abiotic stress responses in rice. Indeed, OsWRKY5 expression in developing leaves is substantially downregulated upon dehydration, suggesting that OsWRKY5 acts as a negative regulator of drought tolerance mechanisms in rice. The loss of OsWRKY5 activity increased sensitivity to ABA, thus promoting ABA-dependent stomatal closure. Also, Arabidopsis thaliana group III WRKY transcription factors, WRKY46, WRKY54, and WRKY70, are involved in drought response. The wrky46 wrky54 wrky70 triple mutant has defects in BR-regulated growth and is more tolerant to drought stress. WRKY46, WRKY54, and WRKY70 are involved in promoting BR-mediated gene expression and inhibiting drought responsive genes. WRKY54 directly interacts with BES1 to cooperatively regulate the expression of target genes. In addition, WRKY54 is phosphorylated and destabilized by GSK3-like kinase BR-INSENSITIVE2, a negative regulator in the BR pathway. So, the above mentioned WRKY TFs are negative regulators of drought stress via two different phytohormone pathways which could further be explored for a better drought tolerance in plants.
Reference:
Chen, J., Nolan, T.M., Ye, H., Zhang, M., Tong, H., Xin, P., Chu, J., Chu, C., Li, Z. and Yin, Y., 2017. Arabidopsis WRKY46, WRKY54, and WRKY70 transcription factors are involved in brassinosteroid-regulated plant growth and drought responses. The Plant Cell, 29(6), pp.1425-1439.
Lim, C., Kang, K., Shim, Y., Yoo, S.C. and Paek, N.C., 2021. Inactivating transcription factor OsWRKY5 enhances drought tolerance through abscisic acid signaling pathways. Plant Physiology.