WRKY: its structure, evolutionary relationship, DNA-binding selectivity, role in stress tolerance and development of plants

Abstract

The plants during their sessile, autotrophic lifestyle are affected by wide range of environmental signals and regulate complex patterns of gene expression with the help of transcription factors. The WRKY transcription factors are considered as plant-specific, however, are also reported in protist, slime mold, fern and pine. The WRKY name is coined from its highly conserved 60 amino acid long WRKY domain. These TFs show W box specific binding which is also influenced by the W box flanking sequence. During evolution, the family has expanded in different patterns to facilitate distinct cellular, developmental, and physiological role in plants. The WRKY TFs form one of the largest families in flowering plants, and play a broad spectrum regulatory role as positive and negative regulators of plant defense regulation, abiotic stresses and also involved in growth and development of plants.

Bacteria-Triggered Systemic Immunity in Barley Is Associated with WRKY and ETHYLENE RESPONSIVE FACTORs But Not with Salicylic Acid

“…S7B). Similar to AP2-ERFs, WRKY TFs are often associated with stress tolerance, responding to biotic and abiotic triggers and to different phytohormones, including SA, JA, and ABA (Agarwal et al, 2011). An increasing body of evidence suggests that WRKY TFs function on the interface between SA, JA, and ABA signaling, balancing different stress tolerance pathways to optimize resistance to biotic and abiotic influences in both Arabidopsis and rice (Pandey and Somssich, 2009;Agarwal et al, 2011;Sharma et al, 2013).…”

“…Similar to AP2-ERFs, WRKY TFs are often associated with stress tolerance, responding to biotic and abiotic triggers and to different phytohormones, including SA, JA, and ABA (Agarwal et al, 2011). An increasing body of evidence suggests that WRKY TFs function on the interface between SA, JA, and ABA signaling, balancing different stress tolerance pathways to optimize resistance to biotic and abiotic influences in both Arabidopsis and rice (Pandey and Somssich, 2009;Agarwal et al, 2011;Sharma et al, 2013). HvWRKY22, for example, is orthologous with AtWRKY30/41/53 (Mangelsen et al, 2008) that are associated with abiotic stress tolerance or the regulation of the cross talk between SA and JA (Miao and Zentgraf, 2007;Higashi et al, 2008;Scarpeci et al, 2013).…”

A systems biology perspective on the role of WRKY transcription factors in drought responses in plants

“…In another study, tobacco plants overexpressing wheat TaWRKY10 show tolerance to multiple stresses including drought (wang et al 2013). wRKY TFs appear to play important roles in regulating water-stress/ drought by modulating the osmotic balance, ROS scavenging and affecting expression of different stress-related genes (Agarwal et al 2011).…”

In silicoidentification, phylogeny and expression analysis of expansin superfamily inMedicago truncatula

“…In addition, there were also lots of TF binding elements identified in the promoters of MtEXP genes, including DOFCOREZM for Dof TF, [31] MYCCONSENSUSAT for MYC TF, [32] WRKY71OS for WRKY TF [33] and ARR1AT for ARF TF. [34] Many of them, such as WRKY, MYC and ARF, are important regulators of plant stress response.…”