Identification and Expression of NAC Transcription Factors of Vaccinium corymbosum L. in Response to Drought Stress

Abstract

Research Highlights: Phenotypic changes and expression profiles, phylogeny, conserved motifs, and expression correlations of NAC (NAM, ATAF1, ATAF2 and CUC2) transcription factors (TFs) in blueberry genome were detected under drought stress, and the expression patterns and functions of 12 NACs were analyzed. Background and Objectives: Blueberry is an important shrub species with a high level of flavonoids in fruit, which are implicated in a broad range of health benefits. However, the molecular mechanism of this shrub species in response to drought stress still remains elusive. NAC TFs widely participate in stress tolerance in many plant species. The characterization and expression profiles of NAC TFs were analyzed on the basis of genome data in blueberry when subjected to drought stress. Materials and Methods: Combined with the analysis of chlorophyll a fluorescence and endogenous phytohormones, the phenotypic changes of blueberry under drought stress were observed. The phylogenetic tree, conserved motifs, differently expressed genes, and expression correlation were determined by means of multiple bioinformatics analysis. The expression profiles of NACs in different organs were examined and compared through RNA-seq and qRT-PCR assay. Results: The chlorophyll a fluorescence parameters φPo, φEo, φRo, and PIabs of leaves were significantly inhibited under drought stress. ABA (abscisic acid) content noticeably increased over the duration of drought, whereas GA3 (gibberellic acid) and IAA (indole acetic acid) content decreased continuously. A total of 158 NACs were identified in blueberry genome and 62 NACs were differently expressed in leaf and root of blueberry under drought stress. Among them, 14 NACs were significantly correlated with the expression of other NAC genes. Conclusions: Our results revealed the phenotypic changes of this shrub under drought stress and linked them with NAC TFs, which are potentially involved in the process of response to drought stress.

NAC Transcription Factor PwNAC11 Activates ERD1 by Interaction with ABF3 and DREB2A to Enhance Drought Tolerance in Transgenic Arabidopsis

“…These results verified the complete network of photoprotective mechanism in OE lines [38]. Recent studies revealed that the inhibition of light energy conversion could produce more excess excitation energy and promote the accumulation of ROS in plant [39]. In grape, Sun et al found that the inhibition of Alternative oxidase (AOX) pathway increased the accumulation of H 2 O 2 , thus resulting in the photoinhibition under heat conditions [40].…”

Genome-wide analysis of MYB transcription factors of Vaccinium corymbosum and their positive responses to drought stress

“…In this study, the 102 VcMYB DEGs were assigned to 16 GO categories (Additional file 6 and Additional file 7). The results showed that 102 DEGs participated in the biological process (38), cellular component (7) and molecular function (21). The "metabolic process" gene (11) was the dominant category in the biological process category accounting for 16.92 %.…”

“…Under the condition of greenhouse, three treatments of plants were applied by withholding irrigation 15 days after transplanting. The soil water content (SWC) reached the predetermined levels without water for 10, 20 and 40 days, respectively [7]. The gravimetric method was employed to control the SWC [72].…”

“…Samples of the three treatments were sent to Shanghai Majorbio Bio-pharm Biotechnology Co., Ltd. (Shanghai, China) for library construction and sequenced by means of Illumina HiSeq xten system (www.majorbio.com) [7]. Total RNA was extracted from the sample using TRIzol® Reagent (Plant RNA Purification Reagent for plant tissue) according the manufacturer's instructions (Invitrogen) and genomic DNA was removed using DNase I (TaKara).…”

“…In order to survive, plants have evolved a set of elaborate and complicated self-regulation networks. Transcription factors (TFs) usually function as key regulators in plants responding to abiotic and biotic stresses [6][7][8]. Among them, MYB TF family was reported to be widely involved in a range of abiotic stresses [9].…”