Expression of CdDHN4, a Novel YSK2-Type Dehydrin Gene from Bermudagrass, Responses to Drought Stress through the ABA-Dependent Signal Pathway

Abstract

Dehydrin improves plant resistance to many abiotic stresses. In this study, the expression profiles of a dehydrin gene, CdDHN4 , were estimated under various stresses and abscisic acid (ABA) treatments in two bermudagrasses ( Cynodon dactylon L.): Tifway (drought-tolerant) and C299 (drought-sensitive). The expression of CdDHN4 was up-regulated by high temperatures, low temperatures, drought, salt and ABA. The sensitivity of CdDHN4 to ABA and the expression of CdDHN4 under drought conditions were higher in Tifway than in C299. A 1239-bp fragment, CdDHN4-P, the partial upstream sequence of the CdDHN4 gene, was cloned by genomic walking from Tifway. Bioinformatic analysis showed that the CdDHN4-P sequence possessed features typical of a plant promoter and contained many typical cis elements, including a transcription initiation site, a TATA-box, an ABRE, an MBS, a MYC, an LTRE, a TATC-box and a GT1-motif. Transient expression in tobacco leaves demonstrated that the promoter CdDHN4-P can be activated by ABA, drought and cold. These results indicate that CdDHN4 is regulated by an ABA-dependent signal pathway and that the high sensitivity of CdDHN4 to ABA might be an important mechanism enhancing the drought tolerance of bermudagrass.

Bacillus amyloliquefaciens Confers Tolerance to Various Abiotic Stresses and Modulates Plant Response to Phytohormones through Osmoprotection and Gene Expression Regulation in Rice

“…Further, increased expression of DHN was reported by Kumar et al (2014) in rice and Kosová et al (2014) in barley and wheat under salt, drought and cold stresses. Interestingly, many DHNs have been identified in plants including Arabidopsis thaliana and wheat that are up-regulated by exogenous ABA under drought stress ( Lv et al, 2017 ). Richard et al (2000) reported exogenous application of JA leads to increase in DHN expression in white spruce.…”

Mechanisms of Environmental Stress Tolerance in Turfgrass

“…Similarly, transcription analysis of creeping bentgrass and annual ryegrass showed that plenty of genes were involved in drought response, and the differentially expressed genes were related to energy metabolism, antioxidants, stress defense, photosynthesis and signaling processes [99,100]. Furthermore, a dehydrin gene in bermudagrass CdDHN4 was obtained, which was regulated by an ABA-dependent signaling pathway to enhance the drought tolerance of bermudagrass [101]. In addition, a number of quantitative trait loci (QTL) related to drought stress were identified in creeping bentgrass [102].…”

Multifunctional Roles of Plant Dehydrins in Response to Environmental Stresses

“…Overexpression of the Solanum habrochaites dehydrins ShDHN enhances transgenic tomato tolerance to multiple abiotic stresses (Liu et al, 2015). Most dehydrins are distributed along with several ubiquitous dehydration-stress response protein types in plants (Bao et al, 2017; Fan et al, 2017). However, some dehydrins were also found distributed in the vegetative tissues of plants grown under normal conditions, which suggested that the dehydrins may play important roles in the plant growth.…”