Wheat WRKY genes TaWRKY2 and TaWRKY19 regulate abiotic stress tolerance in transgenic Arabidopsis plants

Abstract

WRKY-type transcription factors are involved in multiple aspects of plant growth, development and stress response. WRKY genes have been found to be responsive to abiotic stresses; however, their roles in abiotic stress tolerance are largely unknown especially in crops. Here, we identified stress-responsive WRKY genes from wheat (Triticum aestivum L.) and studied their functions in stress tolerance. Forty-three putative TaWRKY genes were identified and two multiple stress-induced genes, TaWRKY2 and TaWRKY19, were further characterized. TaWRKY2 and TaWRKY19 are nuclear proteins, and displayed specific binding to typical cis-element W box. Transgenic Arabidopsis plants overexpressing TaWRKY2 exhibited salt and drought tolerance compared with controls. Overexpression of TaWRKY19 conferred tolerance to salt, drought and freezing stresses in transgenic plants. TaWRKY2 enhanced expressions of STZ and RD29B, and bound to their promoters. TaWRKY19 activated expressions of DREB2A, RD29A, RD29B and Cor6.6, and bound to DREB2A and Cor6.6 promoters. The two TaWRKY proteins may regulate the downstream genes through direct binding to the gene promoter or via indirect mechanism. Manipulation of TaWRKY2 and TaWRKY19 in wheat or other crops should improve their performance under various abiotic stress conditions.

Genome-wide analysis of WRKY gene family in the sesame genome and identification of the WRKY genes involved in responses to abiotic stresses

“…One study showed that co-regulated networks involving WRKY genes were important in regulating the responses of pak-choi to a variety of abiotic stresses [27]. Wheat TaWRKY19 regulates the expression of DREB2A, which encodes a key transcription factor that controls the expression of drought-related genes [56]. Therefore, the regulatory roles of WRKY genes in response to abiotic stresses are complex and further studies are required to understand their functions in sesame.…”

ETHYLENE RESPONSE FACTOR6 Acts as a Central Regulator of Leaf Growth under Water-Limiting Conditions in Arabidopsis

“…Multiple genes encoding stress-related transcription factors were identified within the overlap of putative ERF6 target genes and genes transcriptionally induced within 24 h after osmotic stress exposure (Skirycz et al, 2011a). To further uncover the link between ERF6 and this stress-related transcription factor network, we chose three representative genes, STZ, WRKY33, and MYB51, as these were previously shown to have a role in biotic and abiotic stress signaling (Sakamoto et al, 2000(Sakamoto et al, , 2004Gigolashvili et al, 2007;Jiang and Deyholos, 2009;Birkenbihl et al, 2012;Li et al, 2012;Niu et al, 2012). Additional quantitative PCR analysis confirmed the induction of these genes within 2 h after DEX-mediated ERF6 activation using the ERF6 IOE -S (Fig.…”

Transcriptional Profiling of Resistant and Susceptible Buffalograsses in Response to Blissus occiduus (Hemiptera: Blissidae) Feeding

“…The transcript pre_comp28074_c0_seq1, showed sequence identity (identity: 68%, E value: 2e-14) to a WRKY in Triticum aestivum whose overexpression improves stress tolerance in transgenic Arabidopsis plants through regulation of downstream genes (Niu et al 2012) as well as sequence identity (identity: 86%, E value: 2e-11) with WRKY genes in Brassica napus responding to fungal pathogens (Yang et al 2009). …”