A WRKY transcription factor PbrWRKY53 from Pyrus betulaefolia is involved in drought tolerance and AsA accumulation

Abstract

Summary WRKY comprises a large family of transcription factors in plants, but most WRKY members are still poorly understood. In this study, we report the identification and functional characterization of PbrWRKY53 isolated from Pyrus betulaefolia . PbrWRKY53 was greatly up‐regulated by drought and abscisic acid, but slightly induced by salt and cold. Subcellar localization analyses showed that PbrWRKY53 was located in the nucleus. Ectopic expression of PbrWRKY53 in tobacco and Pyrus ussuriensis conferred enhanced tolerance to drought stress. The transgenic plants exhibited better water status, less reactive oxygen species generation and higher levels of antioxidant enzyme activities and metabolites than the wild type. In addition, overexpression of PbrWRKY53 in transgenic tobacco resulted in enhanced expression level of PbrNCED1 , and led to the increase in larger amount of vitamin C accumulation in comparison to WT. Knock‐down of PbrWRKY53 in P. ussuriensis down‐regulated PbrNCED1 abundance, accompanied by compromised drought tolerance. Yeast one‐hybrid assay, EMSA and transient expression analysis demonstrated that PbrWRKY53 could bind to the W‐box element in the promoter region of PbrNCED1 . Taken together, these results demonstrated that PbrWRKY53 plays a positive role in drought tolerance, which might be, at least in part, promoting production of vitamin C via regulating PbrNCED1 expression.

AcoMYB4, an Ananas comosus L. MYB Transcription Factor, Functions in Osmotic Stress through Negative Regulation of ABA Signaling

“…Four enzymes, superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and peroxidase (POD), play roles in the scavenging of ROS [ 19 , 20 , 21 ]. To elaborate, SOD first catalyzes O 2 − to produce oxygen and H 2 O 2 , and then APX, CAT, and POD metabolize H 2 O 2 to H 2 O through synergistic action [ 17 , 20 , 22 , 23 ]. On the other hand, ROS acts as an important signal molecule involved in plant response to stimuli, having a close relationship with phytohormone ABA [ 24 , 25 , 26 , 27 ].…”

Transcription Factor OpWRKY3 Is Involved in the Development and Biosynthesis of Camptothecin and Its Precursors in Ophiorrhiza pumila Hairy Roots

“…Overexpression of SlWRKY45 enhanced tomato susceptibility to the root-knot nematode Meloidogyne javanica , which was associated with decreased expression of salicylic acid (SA) and jasmonic acid (JA) marker genes [34]. In addition, PbrWRKY53 gene of Pyrus betulaefolia positively regulated the enhanced tolerance to drought stress by regulating PbrNCED1 expression [35]. So far, from all these previous studies, it may conclude that WRKY proteins play important roles in multiple physiological activities.…”

Genome-Wide Analysis of Members of the WRKY Gene Family and Their Cold Stress Response in Prunus mume

“…A total of 58 PpWRKY genes have been identified in the genome of Prunus persica [16]. WRKY proteins have been verified to be essential in the defense response to various biotic and abiotic stresses, including low or high temperature, mechanical damage, and pathogenic infection [17,18,19,20,21,22,23]. In addition, there is a great deal of definite evidence indicating that the regulation of plant development and metabolism also requires WRKYs.…”