Chrysanthemum WRKY gene DgWRKY5 enhances tolerance to salt stress in transgenic chrysanthemum

Abstract

WRKY transcription factors play important roles in plant growth development, resistance and substance metabolism regulation. However, the exact function of the response to salt stress in plants with specific WRKY transcription factors remains unclear. In this research, we isolated a new WRKY transcription factor DgWRKY5 from chrysanthemum. DgWRKY5 contains two WRKY domains of WKKYGQK and two C2H2 zinc fingers. The expression of DgWRKY5 in chrysanthemum was up-regulated under various treatments. Meanwhile, we observed higher expression levels in the leaves contrasted with other tissues. Under salt stress, the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) enzymes in transgenic chrysanthemum were significantly higher than those in WT, whereas the accumulation of H2O2, O2 − and malondialdehyde (MDA) was reduced in transgenic chrysanthemum. Several parameters including root length, root length, fresh weight, chlorophyll content and leaf gas exchange parameters in transgenic chrysanthemum were much better compared with WT under salt stress. Moreover, the expression of stress-related genes DgAPX, DgCAT, DgNCED3A, DgNCED3B, DgCuZnSOD, DgP5CS, DgCSD1 and DgCSD2 was up-regulated in DgWRKY5 transgenic chrysanthemum compared with that in WT. These results suggested that DgWRKY5 could function as a positive regulator of salt stress in chrysanthemum.

TaWRKY51 promotes lateral root formation through negative regulation of ethylene biosynthesis in wheat (Triticum aestivum L.)

“…The WRKY TFs show high binding affinity to the W‐box sequence (T/C)TGAC(C/T) (Rushton et al ., ). The WRKY TFs are known to play critical roles in biotic and abiotic stress responses, such as pathogen infection (Liu et al ., ; Mao et al ., ; Chen et al ., ; Dey et al ., ), high salt (Niu et al ., ; Liang et al ., ), drought stress (Luo et al ., ; Sun et al ., ; Li et al ., ), oxidative stress (Yan et al ., ), nutrient stress (Chen et al ., ; Su et al ., ; Dai et al ., ) and high temperature (Cai et al ., ; He et al ., ). In addition to their important role in stress responses, WRKYs are also involved in a wide range of plant growth and development processes, such as seed dormancy and germination (Luo et al ., ; Zhang et al ., ; Ding et al ., ), seed size (Gu et al ., ), fruit maturation (Cheng et al ., ; Ye et al ., ) and senescence (Besseau et al ., ; Meng et al ., ).…”

Transcriptome Analysis and Differential Gene Expression Profiling of Two Contrasting Quinoa Genotypes in Response to Salt Stress

“…Transcription factors such as NAC, bZIP, AP2/ERF, WRKY, MYB and bHLH regulated the expression of saltresponsive genes and ultimately determined the salt tolerance level of plants [25][26][27][28][29][30]69]. 12 TFs differentially expressed in both genotypes under NaCl treatment were indenti ed in the transcriptome analysis, including three MYBs (AUR62042086, AUR62034188 and AUR62030018), four NACs (AUR62000536, AUR62029344, AUR62015630 and AUR62006885), three WRKYs (AUR62030836, AUR62026996 and AUR62006427), and two ZFPs (AUR62042998 and AUR62009622).…”

“…Plasma membrane bound SbNHXLP (a Na + /H + antiporter-like protein) from sorghum involves in Na + exclusion, maintains ion homeostasis and alleviates NaCl stress in transgenic tomato, and more notably, it increases the fruit yield of tomato [24]. Besides, various transcription factors (TFs) had been shown to participate in salt stress response, such as NAC [25], basic leucine zipper (bZIP) [26], APETALA2/ethylene response factor (AP2/ERF) [27], WRKY [28], basic helix-loop-helix (bHLH) [29] and MYB [30]. They regulate the expression levels of multiple downstream genes, which might ultimately affect salt tolerance of plants.…”

“…Identifying salt-tolerant genes is a vital ingredient of salt-tolerant crop breeding through genetic engineering [54]. Numerous genes and signal pathways related to the response to high salinity have been identi ed in many plants [18][19][20][21][22][23][24][25][26][27][28][29][30], but only a few have been documented in quinoa.…”

Transcriptome analysis and differential gene expression profiling of two contrasting quinoa genotypes in response to salt stress

“…Transcription factors such as NAC, bZIP, AP2/ERF, WRKY, MYB and bHLH regulated the expression of saltresponsive genes and ultimately determined the salt tolerance level of plants [21][22][23][24][25][26]58]. 12 TFs differentially expressed in both genotypes under NaCl treatment were indenti ed in the transcriptome analysis, including three MYBs (AUR62042086, AUR62034188 and AUR62030018), four NACs (AUR62000536, AUR62029344, AUR62015630 and AUR62006885), three WRKYs (AUR62030836, AUR62026996 and AUR62006427), and two ZFPs (AUR62042998 and AUR62009622).…”