ENAC1, a NAC Transcription Factor, is an Early and Transient Response Regulator Induced by Abiotic Stress in Rice (Oryza sativa L.).
ABSTRACT The plant-specific NAC (NAM, ATAF, and CUC)-domain proteins play important roles in plant development and stress responses. In this research, a full-length cDNA named ENAC1 (early NAC-domain protein induced by abiotic stress 1) was isolated from rice. ENAC1 possess one NAC domain in the N-terminus. Comparative time-course expression analysis indicated that ENAC1 expression, similar with OsDREB1A, was induced very quickly by various abiotic stresses including salt, drought, cold, and exogenous abscisic acid. However, the induction of ENAC1 by abiotic stress was transient and lasted up to 3 h, whereas that of OsDREB1A maintained longer. The promoter sequence of ENAC1 harbors several cis-elements including ABA response elements, but the well-known dehydration responsive element/C-repeat element is absent. The ENAC1-GFP (green fluorescent protein) fusion protein was localized in the nucleus of rice protoplast cell. Yeast hybrid assays revealed that ENAC1 was a transcription activator and bound to NAC recognition sequence (NACRS). Co-expression analysis suggested that ENAC1 co-expressed with a number of stress-related genes. Taken together, ENAC1 may be an early transcription activator of stress responses and function in the regulation of NACRS-mediated gene expression under abiotic stress.
- SourceAvailable from: Touming Liu
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- "In contrast, Liu et al. (2014) had previously identified 11 Cd stress-responsive NAC genes from the ramie subjected to only one week of Cd stress treatment. Generally, the expression of regulatory genes, such as NAC TFs, is induced in the early stages of environment stress, and thereafter, these genes activating/inhibiting the expression of their downstream genes in the pathway, and finally resulting in the plant adaptation to the environment stress (Sun et al., 2012). In other words, a stress treatment of 20 days might lead the ramie plants into the late stages of Cd stress response when no NAC genes showed differential expression. "
ABSTRACT: Cadmium (Cd) contamination in agricultural soils has become a major environmental problem in China. Ramie, a fiber crop, has frequently been proposed for use as a phytoremediation crop for the restoration of Cd-contaminated farmlands. However, high levels of Cd can greatly inhibit stem growth in ramie, which reduces its economic value as a crop. To understand the potential mechanisms behind this phenomenon, the ramie genes involved in the Cd stress response were identified using Illumina pair-end sequencing on two Cd-stressed plants (CdS1 and CdS2) and two control plants (CO1 and CO2). Approximately 48.7, 51.6, 41.2, and 47.1 million clean sequence reads were generated from the libraries of CO1, CO2, CdS1, and CdS2, respectively, and de novo assembled to yield 56,932 non-redundant unigenes. A total of 26,686 (46.9%) genes were annotated for their function. Comparison of gene expression levels in CO and CdS ramie revealed 155 differentially expressed genes (DEGs) between treatment and control conditions. Sixteen DEGs were further analyzed for expression differences by using real-time quantitative PCR (qRT-PCR). Among these 16 DEGs, 2 genes encoding GA2-oxidase (a major enzyme for deactivating bioactive gibberellins [GAs]) showed markedly up-regulated expression in Cd stressed ramie. This might be responsible for the growth inhibition of Cd-stressed ramie. Pathway enrichment analysis revealed that the cutin, suberine and wax biosynthesis pathway was markedly enriched by DEGs. The discovery of these Cd stress-responsive genes and pathways will be helpful in further understanding the mechanism of Cd-stress response and improving Cd stress tolerance in ramie. Copyright © 2014. Published by Elsevier B.V.Gene 12/2014; 558(1). DOI:10.1016/j.gene.2014.12.057 · 2.08 Impact Factor
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- "Plants adjust to these stresses through various biochemical and physiological processes, including the accumulation of sugars, proline, and glycine betaine and increasing the expression levels of many genes such as protein kinases (Shinozaki and Yamaguchi-Shinozaki 2000). Protein kinases include mitogen-activated protein (MAP) kinases, calcium-dependent protein kinases (CDPKs), receptorlike kinases, histidine kinases, and serine/threonine protein kinases (Rabbani et al. 2003; Zhou et al. 2007; Sun et al. 2012). Cyclin-dependent kinases (CDKs) are a large family of serine/threonine protein kinases that play important roles in cell proliferation (Doonan and Kitsios 2009). "
ABSTRACT: In our previous research, we showed that the cyclin-dependent kinase regulatory subunit (CKS2) in maize (Zea mays L.) was induced by water deficit and cold stress. To elucidate its expression patterns under adversity, we isolated and characterized its promoter (PZmCKS2). A series of PZmCKS2-deletion derivatives, P0–P3, from the translation start code (−1,455, −999, −367, and −3 bp) was fused to the β-glucuronidase (GUS) reporter gene, and each deletion construct was analyzed by Agrobacterium-mediated steady transformation into Arabidopsis. Leaves were then subjected to dehydration, cold, abscisic acid (ABA), salicylic acid (SA), and methyl jasmonic acid (MeJA). Sequence analysis showed that several stress-related cis-acting elements (MBS, CE3, TGA element, and ABRE) were located within the promoter. Deletion analysis of the promoter, PZmCKS2, suggested that the −999 bp promoter region was required for the highest basal expression of GUS, and the −367 bp sequence was the minimal promoter for ZmCKS2 activation by low temperature, ABA, and MeJA. The cis-acting element ABRE was necessary for promoter activation by exogenous ABA.Acta Physiologiae Plantarum 05/2014; 36(7). DOI:10.1007/s11738-014-1563-3 · 1.52 Impact Factor
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- "The NAC transcription factors are multifunctional proteins with various roles in plant growth and development, such as maintenance of the shoot apical meristem (Souer et al. 1996; Vroemen et al. 2003), lateral root development (Xie et al. 2000), flower formation (Ishida et al. 2000; Li et al. 2011), plant immune responses (Kaneda et al. 2009), plant organ senescence (Kou et al. 2012), embryo development (Kunieda et al. 2008), cell division (Kim et al. 2006), cell growth (Kato et al. 2010), seed germination (Park et al. 2011), senescence (John et al. 1997; Balazadeh et al. 2010, 2011; Yang et al. 2011; Wu et al. 2012; Lee et al. 2012), and formation of secondary walls (Kubo et al. 2005; Mitsuda et al. 2005, 2007; Zhao et al. 2008; Zhong et al. 2010; Yamaguchi et al. 2011; Li et al. 2012). In addition, NAC TFs were also found to participate in plant responses to different abiotic (Tran et al. 2004; Hu et al. 2006; Nakashima et al. 2007; Zheng et al. 2009; Jeong et al. 2010; Gao et al. 2010; Takasaki et al. 2010; Mao et al. 2012; Ze 0 licourt et al. 2012; Jin et al. 2013b; Sun et al. 2012; Kim et al. 2012) and biotic stress (Xie et al. 1999; Ren et al. 2000; Yoshii et al. 2009). "
ABSTRACT: NAM, ATAF, and CUC (NAC) genes are plant-specific transcription factors (TFs) that play key roles in plant growth, development, and stress tolerance. To date, none of the ramie NAC (BnNAC) genes had been identified, even though ramie is one of the most important natural fiber crops. In order to mine the BnNAC TFs and identify their potential function, the search for BnNAC genes against two pools of unigenes de novo assembled from the RNA-seq in our two previous studies was performed, and a total of 32 full-length BnNAC genes were identified in this study. Forty-seven function-known NAC proteins published in other species, in concert with these 32 BnNAC proteins were subjected to phylogenetic analysis, and the result showed that all the 79 NAC proteins can be divided into eight groups (NAC-I-VIII). Among the 32 BnNAC genes, 24, 2, and 1 gene showed higher expression in stem xylem, leaf, and flower, respectively. Furthermore, the expression of 14, 11 and 4 BnNAC genes was regulated by drought, cadmium stress, and infection by root lesion nematode, respectively. Interestingly, there were five BnNAC TFs which showed high homology with the NAC TFs of other species involved in regulating the secondary wall synthesis, and their expressions were not regulated by drought and cadmium stress. These results suggested that the BnNAC family might have a functional diversity. The identification of these 32 full-length BnNAC genes and the characterization of their expression pattern provide a basis for future clarification of their functions in ramie growth and development.MGG Molecular & General Genetics 04/2014; 289(4). DOI:10.1007/s00438-014-0842-4 · 2.83 Impact Factor