Functional Characterization of PsnNAC036 under Salinity and High Temperature Stresses

Abstract

Plant growth and development are challenged by biotic and abiotic stresses including salinity and heat stresses. For Populus simonii × P. nigra as an important greening and economic tree species in China, increasing soil salinization and global warming have become major environmental challenges. We aim to unravel the molecular mechanisms underlying tree tolerance to salt stress and high temprerature (HT) stress conditions. Transcriptomics revealed that a PsnNAC036 transcription factor (TF) was significantly induced by salt stress in P. simonii × P. nigra. This study focuses on addressing the biological functions of PsnNAC036. The gene was cloned, and its temporal and spatial expression was analyzed under different stresses. PsnNAC036 was significantly upregulated under 150 mM NaCl and 37 °C for 12 h. The result is consistent with the presence of stress responsive cis-elements in the PsnNAC036 promoter. Subcellular localization analysis showed that PsnNAC036 was targeted to the nucleus. Additionally, PsnNAC036 was highly expressed in the leaves and roots. To investigate the core activation region of PsnNAC036 protein and its potential regulatory factors and targets, we conducted trans-activation analysis and the result indicates that the C-terminal region of 191–343 amino acids of the PsnNAC036 was a potent activation domain. Furthermore, overexpression of PsnNAC036 stimulated plant growth and enhanced salinity and HT tolerance. Moreover, 14 stress-related genes upregulated in the transgenic plants under high salt and HT conditions may be potential targets of the PsnNAC036. All the results demonstrate that PsnNAC036 plays an important role in salt and HT stress tolerance.

Functional analysis of PagNAC045 transcription factor that improves salt and ABA tolerance in transgenic tobacco

“…In poplar, 289 NAC genes were identified and can be clustered in to 15 distinct subgroups based on their deduced protein sequences [ 42 ]. Among these genes, 37 were significantly upregulated by salt stress according to the RNA-seq data [ 40 ]. Here we studied one of salt-induced NAC genes, PagNAC045 from the 84 K poplar.…”

“…Overexpression of an OsNAC066 in rice improved drought and oxidative stress tolerance and increased ABA sensitivity [ 37 ]. In addition, 289 NAC TFs were retrieved and quantified based on RNA-seq datasets in our previous studies [ 38 – 40 ]. Based on log2 fold change (FC) ≥1 and false discovery rate (FDR) ≤0.05, 37 genes were significantly up-regulated under salt stress [ 40 ] and these genes could be vertically clustered into three groups.…”

“…In addition, 289 NAC TFs were retrieved and quantified based on RNA-seq datasets in our previous studies [ 38 – 40 ]. Based on log2 fold change (FC) ≥1 and false discovery rate (FDR) ≤0.05, 37 genes were significantly up-regulated under salt stress [ 40 ] and these genes could be vertically clustered into three groups. The PagNAC045 TF displayed increased expression under salt stress and was classified into the same group with PagNAC13 (Potri.001G404100.1) [ 35 ] and PagNAC036 (Potri.011G123300.1) [ 40 ].…”

“…In this study, we focused on the PagNAC045 TF gene from the 84 K poplar. The expression of PagNAC045 was significantly induced by salt stress [ 39 , 40 ]. To better understand the characteristics of PagNAC045 , we cloned the gene from the 84 K poplar leaves based on the sequence of a homolog NAC045 from P. trichocarpa.…”

Overexpression of McHB7 Transcription Factor from Mesembryanthemum crystallinum Improves Plant Salt Tolerance

“…The RWC was calculated according to the formula: RWC = [(Fresh Weight − Dry Weight)/(Turgid Weight − Fresh weight)] × 100%. For the analyses of chlorophyll content, SOD, and POD, 0.3 g fresh leaves were used according to previous methods [ 32 , 59 ]. Four biological replicates were used for each sample.…”