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

Abstract

NAC (NAM, ATAF1/2, and CUC2) transcription factors are ubiquitously distributed in eukaryotes and play significant roles in stress response. However, the functional verifications of NACs in Picea (P.) wilsonii remain largely uncharacterized. Here, we identified the NAC transcription factor PwNAC11 as a mediator of drought stress, which was significantly upregulated in P. wilsonii under drought and abscisic acid (ABA) treatments. Yeast two-hybrid assays showed that both the full length and C-terminal of PwNAC11 had transcriptional activation activity and PwNAC11 protein cannot form a homodimer by itself. Subcellular observation demonstrated that PwNAC11 protein was located in nucleus. The overexpression of PwNAC11 in Arabidopsis obviously improved the tolerance to drought stress but delayed flowering time under nonstress conditions. The steady-state level of antioxidant enzymes’ activities and light energy conversion efficiency were significantly increased in PwNAC11 transgenic lines under dehydration compared to wild plants. PwNAC11 transgenic lines showed hypersensitivity to ABA and PwNAC11 activated the expression of the downstream gene ERD1 by binding to ABA-responsive elements (ABREs) instead of drought-responsive elements (DREs). Genetic evidence demonstrated that PwNAC11 physically interacted with an ABA-induced protein—ABRE Binding Factor3 (ABF3)—and promoted the activation of ERD1 promoter, which implied an ABA-dependent signaling cascade controlled by PwNAC11. In addition, qRT-PCR and yeast assays showed that an ABA-independent gene—DREB2A—was also probably involved in PwNAC11-mediated drought stress response. Taken together, our results provide the evidence that PwNAC11 plays a dominant role in plants positively responding to early drought stress and ABF3 and DREB2A synergistically regulate the expression of ERD1.

Drought-Responsive NAC Transcription Factor RcNAC72 Is Recognized by RcABF4, Interacts with RcDREB2A to Enhance Drought Tolerance in Arabidopsis

“…The results of this study are consistent with results of previous works. Apart from that, it has been shown that NACs interact with DREB transcription factors [34,43,44]. The RcNAC72-RcDREB2A interactions in rose were demonstrated through experiments.…”

“…In wheat, TaABRE2 bound to the ABRE cis-acting element on the TaNAC48 promoter, indicating that TaNAC48 was involved in the ABA signaling pathway in response to drought stress in wheat [21]. PwNAC11 could interact with ABF3 to improve drought tolerance in transgenic Arabidopsis [34]. In addition, studies have elaborated that NAC TFs have regulatory relationships with DREB TFs.…”

“…Lily LlNAC2 can interoperate with LlDREB1 in response to low temperature stress [35]. PwNAC11 can interact with PwDREB2A to enhance drought tolerance [34].…”

The Putative Role of the NAC Transcription Factor EjNACL47 in Cell Enlargement of Loquat (Eriobotrya japonica Lindl.)

“…Plant NAC is derived from the acronym NAM (no apical meristem) cloned from Petunia hybrida in 1996 [16] and ATAF1/2 and CUC2 (cup-shaped cotyledon) cloned from Arabidopsis thaliana [17]. Numerous studies show that NAC plays important roles in plant growth and development, response to stress, and other processes [16][17][18][19][20][21][22][23]. Rose (Rosa hybrida) RhNAC100 regulates the expression of genes related to cell elongation [22].…”

“…Additionally, grapevine (Vitis vinifera) VviNAC33 facilitates the transition from a vegetative to mature phase by inducing leaf degreening and growth cessation [19], and FaRIF is a key regulator of strawberry fruit ripening from early developmental stages by controlling abscisic acid biosynthesis and signaling, cell wall degradation and modification, the phenylpropanoid pathway, volatile production, and the balance of aerobic/anaerobic metabolism [20]. Moreover, Picea wilsonii PwNAC11 plays a dominant role in plants that respond positively to early drought stress [21]. However, relatively few studies have been conducted on NAC in relation to loquat.…”