•Wheat MYB gene TaMyb1D was cloned.•The expression levels of TaMyb1D was induced under PEG and H2O2 treatments.•TaMyb1D regulated phenylpropanoid metabolism and affected plant development.•TaMyb1D ...enhanced drought and oxidative stress tolerance in transgenic tobacco plants.
MYB transcription factors are involved in the regulation of plant development and response to biotic and abiotic stress. In this study, TaMyb1D, a novel subgroup 4 gene of the R2R3-MYB subfamily, was cloned from wheat (Triticum aestivum L.). TaMyb1D was localized in the nucleus and functioned as a transcriptional repressor. The overexpression of TaMyb1D in tobacco (Nicotiana tabacum) plants repressed the expression of genes related to phenylpropanoid metabolism and down-regulated the accumulation of lignin in stems and flavonoids in leaves. These changes affected plant development under normal conditions. The expression of TaMyb1D was ubiquitous and up-regulated by PEG6000 and H2O2 treatments in wheat. TaMyb1D-overexpressing transgenic tobacco plants exhibited higher relative water content and lower water loss rate during drought stress, as well as higher chlorophyll content in leaves during oxidative stress. The transgenic plants showed a lower leakage of ions as well as reduced malondialdehyde and H2O2 levels during conditions of drought and oxidative stresses. In addition, TaMyb1D up-regulated the expression levels of ROS- and stress-related genes in response to drought stress. Therefore, the overexpression of TaMyb1D enhanced tolerance to drought and oxidative stresses in tobacco plants. Our study demonstrates that TaMyb1D functions as a negative regulator of phenylpropanoid metabolism and a positive regulator of plant tolerance to drought and oxidative stresses.
MYB transcription factors play important roles in plant responses to biotic and abiotic stress. In this study,
, a R2R3-MYB gene, was cloned from wheat (
L.). TaODORANT1 was localized in the nucleus ...and functioned as a transcriptional activator.
was up-regulated in wheat under PEG6000, NaCl, ABA, and H
O
treatments.
-overexpressing transgenic tobacco plants exhibited higher relative water content and lower water loss rate under drought stress, as well as lower Na
accumulation in leaves under salt stress. The transgenic plants showed higher CAT activity but lower ion leakage, H
O
and malondialdehyde contents under drought and salt stresses. Besides, the transgenic plants also exhibited higher SOD activity under drought stress. Our results also revealed that
overexpression up-regulated the expression of several ROS- and stress-related genes in response to both drought and salt stresses, thus enhancing transgenic tobacco plants tolerance. Our studies demonstrate that TaODORANT1 positively regulates plant tolerance to drought and salt stresses.
Calcineurin B-like protein-interacting protein kinases (CIPKs) have been found to be responsive to abiotic stress. However, their precise functions and the related molecular mechanisms in abiotic ...stress tolerance are not completely understood, especially in wheat. In the present study, TaCIPK29 was identified as a new member of CIPK gene family in wheat. TaCIPK29 transcript increased after NaCl, cold, methyl viologen (MV), abscisic acid (ABA) and ethylene treatments. Over-expression of TaCIPK29 in tobacco resulted in increased salt tolerance, which was demonstrated by higher germination rates, longer root lengths and better growth status of transgenic tobacco plants compared to controls when both were treated with salt stress. Physiological measurements indicated that transgenic tobacco seedlings retained high K(+)/Na(+) ratios and Ca(2+) content by up-regulating some transporter genes expression and also possessed lower H2O2 levels and reduced membrane injury by increasing the expression and activities of catalase (CAT) and peroxidase (POD) under salt stress. Moreover, transgenic lines conferred tolerance to oxidative stress by increasing the activity and expression of CAT. Finally, TaCIPK29 was located throughout cells and it preferentially interacted with TaCBL2, TaCBL3, NtCBL2, NtCBL3 and NtCAT1. Taken together, our results showed that TaCIPK29 functions as a positive factor under salt stress and is involved in regulating cations and reactive oxygen species (ROS) homeostasis.
Calcineurin B-like protein interacting protein kinases (CIPKs) are vital elements in plant abiotic stress signaling pathways. However, the functional mechanism of CIPKs has not been understood ...clearly, especially in
, a new monocot model plant. In this study,
a
gene from
was characterized.
was downregulated by polyethylene glycol, NaCl, H
O
, and abscisic acid (ABA) treatments. Transgenic tobacco plants overexpressing
presented improved drought and salt tolerance, and displayed hypersensitive response to exogenous ABA. Further investigations revealed that BdCIPK31 functioned positively in ABA-mediated stomatal closure, and transgenic tobacco exhibited reduced water loss under dehydration conditions compared with the controls. BdCIPK31 also affected Na
/K
homeostasis and root K
loss, which contributed to maintain intracellular ion homeostasis under salt conditions. Moreover, the reactive oxygen species scavenging system and osmolyte accumulation were enhanced by
overexpression, which were conducive for alleviating oxidative and osmotic damages. Additionally, overexpression of
could elevate several stress-associated gene expressions under stress conditions. In conclusion, BdCIPK31 functions positively to drought and salt stress through ABA signaling pathway. Overexpressing
functions in stomatal closure, ion homeostasis, ROS scavenging, osmolyte biosynthesis, and transcriptional regulation of stress-related genes.
Sucrose non-fermenting 1-related protein kinase 2 (SnRK2) family members play crucial roles in plant abiotic stress response. However, the precise mechanism underlying the function of SnRKs has not ...been thoroughly elucidated in plants. In this research, a novel
gene,
was cloned and characterized from common wheat. The expression of
was upregulated by polyethylene glycol (PEG), NaCl, H
O
, abscisic acid (ABA), methyl jasmonate (MeJA), and ethrel treatments.
was mainly expressed in wheat young root, stamen, pistil, and lemma. Overexpressing
in transgenic tobacco enhanced plants' tolerance to drought and salt stresses both in young seedlings and mature plants with improved survival rate, seed germination rate, and root length. Physiological analyses suggest that TaSnRK2.9 improved antioxidant system such as superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), and glutathione (GSH) to reduce the H
O
content under drought or salt stress. Additionally,
overexpression plants had elevated ABA content, implying that the function of TaSnRK2.9 may be ABA-dependent. Moreover, TaSnRK2.9 increased the expression of some ROS-related, ABA-related, and stress-response genes under osmotic or salt treatment. TaSnRK2.9 could interact with NtABF2 in yeast two-hybrid assay, and increased the expression of
under mannitol or NaCl treatment in transgenic tobacco plants. In conclusion, overexpression of
in tobacco conferred plants tolerance to drought and salt stresses through enhanced ROS scavenging ability, ABA-dependent signal transduction, and specific SnRK-ABF interaction.
Calcineurin B‐like protein‐interacting protein kinases (CIPKs) are components of Ca2+ signaling in responses to abiotic stresses. In this work, the full‐length cDNA of a novel CIPK gene (TaCIPK14) ...was isolated from wheat and was found to have significant sequence similarity to OsCIPK14/15. Subcellular localization assay revealed the presence of TaCIPK14 throughout the cell. qRT‐PCR analysis showed that TaCIPK14 was upregulated under cold conditions or when treated with salt, PEG or exogenous stresses related signaling molecules including ABA, ethylene and H2O2. Transgenic tobaccos overexpressing TaCIPK14 exhibited higher contents of chlorophyll and sugar, higher catalase activity, while decreased amounts of H2O2 and malondialdehyde, and lesser ion leakage under cold and salt stresses. In addition, overexpression also increased seed germination rate, root elongation and decreased Na+ content in the transgenic lines under salt stress. Higher expression of stress‐related genes was observed in lines overexpressing TaCIPK14 compared to controls under stress conditions. In summary, these results suggested that TaCIPK14 is an abiotic stress‐responsive gene in plants.
Microelement contents and metabolism are vitally important for cereal plant growth and development as well as end-use properties. While minerals phytotoxicity harms plants, microelement deficiency ...also affects human health. Genetic engineering provides a promising way to solve these problems. As plants vary in abilities to uptake, transport, and accumulate minerals, and the key enzymes acting on that process is primarily presented in this review. Subsequently, microelement function and biosafety assessment of transgenic cereal plants have become a key issue to be addressed. Progress in genetic engineering of cereal plants has been made with the introduction of quality, high-yield, and resistant genes since the first transgenic rice, corn, and wheat were born in 1988, 1990, and 1992, respectively. As the biosafety issue of transgenic cereal plants has now risen to be a top concern, many studies on transgenic biosafety have been carried out. Transgenic cereal biosafety issues mainly include two subjects, environmental friendliness and end-use safety. Different levels of gene confirmation, genomics, proteomics, metabolomics and nutritiomics, absorption, metabolism, and function have been investigated. Also, the different levels of microelement contents have been measured in transgenic plants. Based on the motivation of the requested biosafety, systematic designs, and analysis of transgenic cereal are also presented in this review paper.
Potassium (K) is one of the most essential macronutrients for plants. However, K+ is deficient in some cultivated soils. Hence, improving the efficiencies of K+ uptake and utilization is important ...for agricultural production. Ca2+ signaling pathways play an important role in regulation of K+ acquisition. In the present study, BdCIPK31, a Calcineurin B-like protein interacting protein kinase (CIPK) from Brachypodium distachyon, was found to be a potential positive regulator in plant response to low K+ stress. The expression of BdCIPK31 was responsive to K+-deficiency, and overexpression of BdCIPK31 conferred enhanced tolerance to low K+ stress in transgenic tobaccos. Furthermore, BdCIPK31 was demonstrated to promote the K+ uptake in root, and could maintain normal root growth under K+-deficiency conditions. Additionally, BdCIPK31 functioned in scavenging excess reactive oxygen species (ROS), reduced oxidative damage caused by low K+ stress. Collectively, our study indicates that BdCIPK31 is a vital regulatory component in K+-acquisition system in plants.
•A new multi-function regulator in plant K+ utilization has been discovered.•BdCIPK31 enhances root K+ uptake, but doesn't affect root-shoot K+ transport.•BdCIPK31 promotes sugar transport under low K+ stress, contributes to root growth.•BdCIPK31 enhances ROS-scavenging, reduces oxidative damage caused by K-starving.
In plants, calcium-dependent protein kinases (CDPKs) are involved in tolerance to abiotic stresses and in plant seed development. However, the functions of only a few rice CDPKs have been clarified. ...At present, it is unclear whether CDPKs also play a role in regulating spikelet fertility.
We cloned and characterized the rice CDPK gene, OsCPK9. OsCPK9 transcription was induced by abscisic acid (ABA), PEG6000, and NaCl treatments. The results of OsCPK9 overexpression (OsCPK9-OX) and OsCPK9 RNA interference (OsCPK9-RNAi) analyses revealed that OsCPK9 plays a positive role in drought stress tolerance and spikelet fertility. Physiological analyses revealed that OsCPK9 improves drought stress tolerance by enhancing stomatal closure and by improving the osmotic adjustment ability of the plant. It also improves pollen viability, thereby increasing spikelet fertility. In OsCPK9-OX plants, shoot and root elongation showed enhanced sensitivity to ABA, compared with that of wild-type. Overexpression and RNA interference of OsCPK9 affected the transcript levels of ABA- and stress-responsive genes.
Our results demonstrated that OsCPK9 is a positive regulator of abiotic stress tolerance, spikelet fertility, and ABA sensitivity.
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