Abscisic acid (ABA) and low temperatures synergistically increase the expression of CBF/DREB1 transcription factors and cold-hardiness in grapevine dormant buds

Abstract

• Background and Aims It has been reported that low temperatures (LTs) and the plant hormone abscisic acid (ABA) induce the expression of CBF/DREB1 transcription factors in vegetative tissues and seedlings of Vitis vinifera and Vitis riparia and that foliar applications of ABA to V. vinifera increase the freezing tolerance or coldhardiness of dormant buds. However, the combined effect of ABA and LTs on the expression of CBF/DREB1 transcription factors and on the acquisition of freezing tolerance in dormant grapevine buds has not been investigated. The objective of this study was to analyse the combined effect of ABA and LT treatments on the expression of CBF/DREB transcription factors and the acquisition of freezing tolerance. • Methods In vitro experiments with single-bud cuttings of grapevines were used to analyse the effect of ABA, ABA + LT and LT on the expression of CBF/DREB transcription factors, dehydrin and antioxidant genes, the acquisition of freezing tolerance and the endogenous content of ABA. Gene expression analysis was performed by quantitative real-time PCR and freezing tolerance was determined by measuring the low-temperature exotherm by differential thermal analysis. ABA levels were determined by gas chromatography coupled to an electron capture detector. • Key Results The LT treatment and exogenous application of ABA to grapevine dormant buds increased the expression of the CBF/DREB1 transcription factors VvCBF2, VvCBF3, VvCBF4 and VvCBF6. The joint application of LT and ABA produced a huge increase in the expression of these transcription factors, which was greater than the sum of the increases produced by them individually, which indicates the existence of a synergistic effect between ABA and LT on the activation of these transcription factors. This synergic effect was also observed on the increase in bud cold-hardiness and on the expression of antioxidant and dehydrin genes. • Conclusions The synergy between ABA and LT on the expression of CBF/DREB1 transcription factors VvCBF2, VvCBF3, VvCBF4 and VvCBF6 plays a key role in cold acclimatization of grapevine buds. The results highlight the importance of the combination of stimuli in the improvement of genetic and physiological responses and help us to understand the adaption of plants to complex environments.

Differential expression analysis of genes in the root crown of alfalfa under low-temperature stress

“…Similar results have also been found with the overexpression of TaSnRK2.3 in Arabidopsis, which results in an improved root-system structure and significantly enhanced the tolerance of this species to freezing stress [48]. In addition, low-temperature stress and ABA synergistically (in Vitis vinifera buds) increased the expression of CBF/DREB1 TFs (VvCBF2, VvCBF3, VvCBF4, and VvCBF6) [49], and increased the cold resistance of the Longmu 806 variety, indicating that Longmu 806 is more likely to resist complex low-temperature environments than Sardi.…”

Different Genes Express Analysis of root crown of alfalfa under low temperature stress

“…A total of 57,712 unigenes (50.37% of total 114,563 unigenes) were annotated against Nr, SwissProt, Pfam, COG, GO and KEGG databases using BLASTX (E-value < 1 ´ 10 -5 ). Among them, 56 2a). According to the Nr database, 10.59% (5,933) of unigenes showed homology (1 ´ E -10 < E-value ≤ 1 ´ E -5 ), 14.37% (8,051) of unigenes showed strong homology (1 ´ E -20 < E-value ≤ 1E -10 ), and the remaining of 62.68% (35,133) unigenes had very strong homology (E-value ≤ 1E -30 ) (Fig.…”

“…This indicated that the SnRK2 gene regulated the low temperature stress response by controlling the expression of stress-responsive genes in a low temperature environment. Moreover, the low temperature stress and ABA synergistically increase the expression of CBF/DREB1 transcription factors [56], which may help to the resistance of alfalfa to low temperature complex environments.…”

Isoform Sequencing Provides Insight Into Freezing Response of Common Wheat (Triticum aestivum L.)

“…Previous studies have shown that the cold acclimation is an adaptation process involving multiple biochemical and physiological changes, which regulated by the induced expression or repression of a series of regulatory and functional genes (Li et al, 2015;Ma et al, 2015;Mao et al, 2019). Understanding the molecular mechanisms in the cold response is important to improve cold tolerance using molecular techniques (Rubio et al, 2018;Ye et al, 2019). Transcriptome sequencing has been proven to be an efficient method for cold-related gene discovery, which has been studied extensively in Arabidopsis (Lee et al, 2005) and cereal crops such as rice (Zhang et al, 2012), maize (Trzcinska-Danielewicz et al, 2009), barley (Tommasini et al, 2008), and wheat (Gulick et al, 2005).…”