Maintenance of homeostasis is pivotal to all forms of life. In the case of plants, homeostasis is constantly threatened by the inability to escape environmental fluctuations, and therefore sensitive mechanisms must ha...Maintenance of homeostasis is pivotal to all forms of life. In the case of plants, homeostasis is constantly threatened by the inability to escape environmental fluctuations, and therefore sensitive mechanisms must have evolved to allow rapid perception of environmental cues and concomitant modification of growth and developmental patterns for adaptation and survival. Re-establishment of homeostasis in response to environmental perturbations requires reprog- ramming of metabolism and gene expression to shunt energy sources from growth-related biosynthetic processes to defense, acclimation, and, ultimately, adaptation. Failure to mount an initial ＇emergency＇ response may result in nutrient deprivation and irreversible senescence and cell death. Early signaling events largely determine the capacity of plants to orchestrate a successful adaptive response. Early events, on the other hand, are likely to be shared by different conditions through the generation of similar signals and before more specific responses are elaborated. Recent studies lend credence to this hypothesis, underpinning the importance of a shared energy signal in the transcriptional response to various types of stress. Energy deficiency is associated with most environmental perturbations due to their direct or indirect deleterious impact on photosynthesis and/or respiration. Several systems are known to have evolved for monitoring the available resources and triggering metabolic, growth, and developmental decisions accordingly. In doing so, energy-sensing systems regulate gene expression at multiple levels to allow flexibility in the diversity and the kinetics of the stress response.展开更多
DREB转录因子(Dehydration Responsive Element Binding Protein),属于植物AP2/ERF转录因子超家族。DREB转录因子广泛参与干旱、高盐、冷、热等多种胁迫应答反应,是近年来研究最为广泛,在植物抗性提高方面颇具潜力的转录因子之一。本研...DREB转录因子(Dehydration Responsive Element Binding Protein),属于植物AP2/ERF转录因子超家族。DREB转录因子广泛参与干旱、高盐、冷、热等多种胁迫应答反应,是近年来研究最为广泛,在植物抗性提高方面颇具潜力的转录因子之一。本研究综述了DREB基因家族的分类法、基因结构特征,重点指出了DREB基因的复杂性及其研究的局限性,并对以后DREB基因的研究方向进行了展望。展开更多
NAC proteins are plant-specific transcription factors and enriched with members involved in plant response to drought stress. In this study, we analyzed the expression profiles of TaNAC69 in bread wheat using Affymetr...NAC proteins are plant-specific transcription factors and enriched with members involved in plant response to drought stress. In this study, we analyzed the expression profiles of TaNAC69 in bread wheat using Affymetrix Wheat Genome Array datasets and quantitative RT-PCR. TaNAC69 expression was positively associated with wheat responses to both abiotic and biotic stresses and was closely correlated with a number of stress up-regulated genes. The functional analyses of TaNAC69 in transgenic wheat showed that TaNAC69 driven by a barley drought-inducible HvDhn4s promoter led to marked drought-inducible overexpression of TaNAC69 in the leaves and roots of transgenic lines. The HvDhn4s：Ta- NAC69 transgenic lines produced more shoot biomass under combined mild salt stress and water-limitation conditions, had longer root and more root biomass under polyethylene glycol-induced dehydration. Analysis of transgenic lines with constitutive overexpression of TaNAC69 showed the enhanced expression levels of several stress up-regulated genes. DNA-binding assays revealed that TaNAC69 and its rice homolog （ONAC131） were capable of binding to the promoter elements of three rice genes （chitinase, ZlM, and glyoxalase I） and an Arabidopsis glyoxalase I family gene, which are homologs of TaNAC69 up-regulated stress genes. These data suggest that TaNAC69 is involved in regulating stress upregulated genes and wheat adaptation to drought stress.展开更多
文摘Maintenance of homeostasis is pivotal to all forms of life. In the case of plants, homeostasis is constantly threatened by the inability to escape environmental fluctuations, and therefore sensitive mechanisms must have evolved to allow rapid perception of environmental cues and concomitant modification of growth and developmental patterns for adaptation and survival. Re-establishment of homeostasis in response to environmental perturbations requires reprog- ramming of metabolism and gene expression to shunt energy sources from growth-related biosynthetic processes to defense, acclimation, and, ultimately, adaptation. Failure to mount an initial ＇emergency＇ response may result in nutrient deprivation and irreversible senescence and cell death. Early signaling events largely determine the capacity of plants to orchestrate a successful adaptive response. Early events, on the other hand, are likely to be shared by different conditions through the generation of similar signals and before more specific responses are elaborated. Recent studies lend credence to this hypothesis, underpinning the importance of a shared energy signal in the transcriptional response to various types of stress. Energy deficiency is associated with most environmental perturbations due to their direct or indirect deleterious impact on photosynthesis and/or respiration. Several systems are known to have evolved for monitoring the available resources and triggering metabolic, growth, and developmental decisions accordingly. In doing so, energy-sensing systems regulate gene expression at multiple levels to allow flexibility in the diversity and the kinetics of the stress response.
文摘DREB转录因子(Dehydration Responsive Element Binding Protein),属于植物AP2/ERF转录因子超家族。DREB转录因子广泛参与干旱、高盐、冷、热等多种胁迫应答反应,是近年来研究最为广泛,在植物抗性提高方面颇具潜力的转录因子之一。本研究综述了DREB基因家族的分类法、基因结构特征,重点指出了DREB基因的复杂性及其研究的局限性,并对以后DREB基因的研究方向进行了展望。
文摘NAC proteins are plant-specific transcription factors and enriched with members involved in plant response to drought stress. In this study, we analyzed the expression profiles of TaNAC69 in bread wheat using Affymetrix Wheat Genome Array datasets and quantitative RT-PCR. TaNAC69 expression was positively associated with wheat responses to both abiotic and biotic stresses and was closely correlated with a number of stress up-regulated genes. The functional analyses of TaNAC69 in transgenic wheat showed that TaNAC69 driven by a barley drought-inducible HvDhn4s promoter led to marked drought-inducible overexpression of TaNAC69 in the leaves and roots of transgenic lines. The HvDhn4s：Ta- NAC69 transgenic lines produced more shoot biomass under combined mild salt stress and water-limitation conditions, had longer root and more root biomass under polyethylene glycol-induced dehydration. Analysis of transgenic lines with constitutive overexpression of TaNAC69 showed the enhanced expression levels of several stress up-regulated genes. DNA-binding assays revealed that TaNAC69 and its rice homolog （ONAC131） were capable of binding to the promoter elements of three rice genes （chitinase, ZlM, and glyoxalase I） and an Arabidopsis glyoxalase I family gene, which are homologs of TaNAC69 up-regulated stress genes. These data suggest that TaNAC69 is involved in regulating stress upregulated genes and wheat adaptation to drought stress.
