Plant Biotechnol J , IF:8.154 , 2019 Sep , V17 (9) : P1834-1849 doi: 10.1111/pbi.13104
The bZIP73 transcription factor controls rice cold tolerance at the reproductive stage.
State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China.; Department of Biological Sciences, Marquette University, Milwaukee, WI, USA.; State Key Laboratory of Hybrid Rice, China National Hybrid Rice Research and Development Center, Changsha, China.; University of Chinese Academy of Sciences, Beijing, China.
Cold temperature during the reproductive stage often causes great yield loss of grain crops in subtropical and temperate regions. Previously we showed that the rice transcription factor bZIP73(Jap) plays an important role in cold adaptation at the seedling stage. Here we further demonstrate that bZIP73(Jap) also confers cold stress tolerance at the reproductive stage. bZIP73(Jap) was up-regulated under cold treatment and predominately expressed in panicles at the early binucleate and flowering stages. bZIP73(Jap) forms heterodimers with bZIP71, and co-expression of bZIP73(Jap) and bZIP71 transgenic lines significantly increased seed-setting rate and grain yield under natural cold stress conditions. bZIP73(Jap) :bZIP71 not only repressed ABA level in anthers, but also enhanced soluble sugar transport from anthers to pollens and improved pollen grain fertility, seed-setting rate, and grain yield. Interestingly, bZIP73(Jap) :bZIP71 also regulated the expression of qLTG3-1(Nip) , and qLTG3-1(Nip) overexpression lines greatly improved rice tolerance to cold stress during the reproductive stage. Therefore, our work establishes a framework for rice cold stress tolerance through the bZIP71-bZIP73(Jap) -qLTG3-1(Nip) -sugar transport pathway. Together with our previous work, our results provide a powerful tool for improving rice cold stress tolerance at both the seedling and the reproductive stages.
PMID: 30811812
Sci Total Environ , IF:6.551 , 2019 Sep , V681 : P191-201 doi: 10.1016/j.scitotenv.2019.05.127
Identification of putative key genes for coastal environments and cold adaptation in mangrove Kandelia obovata through transcriptome analysis.
Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian 361102, China.; Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian 361102, China; Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, CA 91766, USA. Electronic address: qqli@westernu.edu.
Mangrove forests are an important contributor to the coastal marine environment. They have developed unique adaptations to the harsh coastal wetland, yet their geographic distribution is limited by environmental temperature. The adaptive strategies of mangrove at the molecular level, however, have not been addressed. In the present work, transcriptome analyses were performed on different cold damaged plants of a mangrove species, Kandelia obovata. From the samples collected in the field after a cold stress, we found that distinct expression profiles of many key genes are related to extreme temperature responses. These include transcription factors such as WRKY and bHLH, and other genes encoding proteins like SnRK2, PR-1, KCS, involving in the pathways of plant hormones, plant-pathogen interactions, and long chain fatty acid synthesis. We also examined the transcriptomes of eight tissues of K. obovata to identify candidate genes involved in adaptation and development. While stress-responsive genes were globally expressed, tissue-specific genes with diverse functions might be involved in tissue development and adaptability. For examples, genes encoding CYP724B1 and ABCB1 were specifically expressed in the fruit and root, respectively. Additionally, 26 genes were identified as positively selected genes in K. obovata, six of them were found to be involved in chilling stress response, seed germination and oxidation-reduction processes, suggesting their roles in stressful environment adaptation. Together, these results shed light into the K. obovata's natural responses to cold snaps at the molecular level, and reveal a global gene expression portrait across different tissues. It also provides a transcriptome resource for further molecular ecology studies and conservation planning of this and other mangrove plants in their native and adopted environments.
PMID: 31103657
Plant Cell Environ , IF:6.362 , 2019 Sep , V42 (9) : P2645-2663 doi: 10.1111/pce.13579
Cold stress activates disease resistance in Arabidopsis thaliana through a salicylic acid dependent pathway.
School of Life Sciences, Central China Normal University, Wuhan, 43009, P.R. China.; School of Biological Sciences and Technology, Liupanshui Normal University, Liupanshui, 553004, P.R. China.; Department of Chemistry and Biochemistry, Texas Tech University, Lubbock 79409, Texas, USA.
Exposure to short-term cold stress influences disease resistance by mechanisms that remain poorly characterized. The molecular basis of cold-activated immunity was therefore investigated in Arabidopsis thaliana inoculated with the bacterial pathogen Pst DC3000, using a transcriptomic analysis. Exposure to cold stress for 10 hr was sufficient to activate immunity, as well as H2 O2 accumulation and callose deposition. Transcriptome changes induced by the 10-hr cold treatment were similar to those caused by pathogen infection, including increased expression of the salicylic acid (SA) pathway marker genes, PR2 and PR5, and genes playing positive roles in defence against (hemi)-biotrophs. In contrast, transcripts encoding jasmonic acid (JA) pathway markers such as PR4 and MYC2 and transcripts with positive roles in defence against necrotrophs were less abundant following the 10-hr cold treatment. Cold-activated immunity was dependent on SA, being partially dependent on NPR1 and ICS1/SID2. In addition, transcripts encoding SA biosynthesis enzymes such as ICS2, PAL1, PAL2, and PAL4 (but not ICS1/SID2) and MES9 were more abundant, whereas GH3.5/WES1 and SOT12 transcripts that encode components involved in SA modification were less abundant following cold stress treatment. These findings show that cold stress cross-activates innate immune responses via a SA-dependent pathway.
PMID: 31087367
Genomics , IF:6.205 , 2019 Sep , V111 (5) : P1006-1017 doi: 10.1016/j.ygeno.2018.05.014
High throughput sequencing identifies chilling responsive genes in sweetpotato (Ipomoea batatas Lam.) during storage.
Institute of Integrative Plant Biology, School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu 221116, China; Jiangsu Key Laboratory of Phylogenomics and Comparative Genomics, Jiangsu Normal University, Xuzhou, Jiangsu 221116, China.; Institute of Integrative Plant Biology, School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu 221116, China; Xuzhou Institute of Agricultural Sciences in Xuhuai District, Jiangsu Xuzhou Sweetpotato Research Center, Sweetpotato Research Institute, CAAS, Xuzhou, Jiangsu 221116, China.; Xuzhou Institute of Agricultural Sciences in Xuhuai District, Jiangsu Xuzhou Sweetpotato Research Center, Sweetpotato Research Institute, CAAS, Xuzhou, Jiangsu 221116, China; Key Laboratory of Biology and Genetic Improvement of Sweetpotato, Ministry of Agriculture, Xuzhou, Jiangsu 221116, China.; Department of Biology, East Carolina University, Greenville, NC 27858, USA.; Institute of Integrative Plant Biology, School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu 221116, China; Jiangsu Key Laboratory of Phylogenomics and Comparative Genomics, Jiangsu Normal University, Xuzhou, Jiangsu 221116, China. Electronic address: hanyonghua@jsnu.edu.cn.; Institute of Integrative Plant Biology, School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu 221116, China; Jiangsu Key Laboratory of Phylogenomics and Comparative Genomics, Jiangsu Normal University, Xuzhou, Jiangsu 221116, China. Electronic address: zongyunli@jsnu.edu.cn.
Sweetpotato (Ipomoea batatas L.) is a globally important economic food crop. It belongs to Convolvulaceae family and origins in the tropics; however, sweetpotato is sensitive to cold stress during storage. In this study, we performed transcriptome sequencing to investigate the sweetpotato response to chilling stress during storage. A total of 110,110 unigenes were generated via high-throughput sequencing. Differentially expressed genes (DEGs) analysis showed that 18,681 genes were up-regulated and 21,983 genes were down-regulated in low temperature condition. Many DEGs were related to the cell membrane system, antioxidant enzymes, carbohydrate metabolism, and hormone metabolism, which are potentially associated with sweetpotato resistance to low temperature. The existence of DEGs suggests a molecular basis for the biochemical and physiological consequences of sweetpotato in low temperature storage conditions. Our analysis will provide a new target for enhancement of sweetpotato cold stress tolerance in postharvest storage through genetic manipulation.
PMID: 29792923
Plant J , IF:6.141 , 2019 Sep , V99 (5) : P988-1002 doi: 10.1111/tpj.14378
The ethylene response factor VaERF092 from Amur grape regulates the transcription factor VaWRKY33, improving cold tolerance.
Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China.; Beijing Key Laboratory of Grape Sciences and Enology, CAS Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.; Ecology and Evolution, Research School of Biology, Australian National University, Acton, ACT, 2601, Australia.
Cold stress is a major limiting factor in grape (Vitis) productivity. In this study, we characterized a cold-responsive ethylene response factor (ERF) transcription factor, VaERF092, from Amur grape (Vitis amurensis). VaERF092 expression was induced by both low temperatures and the ethylene precursor 1-aminocyclopropane-1-carboxylate (ACC), but was suppressed by treatment with the ethylene inhibitor aminoethoxyvinylglycine (AVG) under cold conditions. Ectopic expression of VaERF092 in Arabidopsis thaliana enhanced cold tolerance. Co-expression network analysis of V. vinifera genes indicated that WRKY33 might be a downstream target of VaERF092. This hypothesis was supported by the fact that VaWRKY33 was expressed temporally after VaERF092 expression and could also be induced by cold and ACC, and inhibited by AVG. Yeast one-hybrid, transient beta-glucuronidase (GUS) and dual-luciferase reporter assays provided evidence for an interaction between VaERF092 and a GCC-box element in the VaWRKY33 promoter. In addition, heterologous overexpression of VaWRKY33 in A. thaliana resulted in enhanced cold tolerance. VaERF092- and VaWRKY33 overexpressing grape calli showed lower low-temperature exothermic values than the empty vector (EV) calli, indicating enhanced tolerance to cold. Together, these results indicated that VaERF092 regulates VaWRKY33 through binding to its promoter GCC-box, leading to enhanced cold stress tolerance.
PMID: 31063661
J Exp Bot , IF:5.908 , 2019 Sep , V70 (18) : P4595-4604 doi: 10.1093/jxb/erz229
Deacclimation after cold acclimation-a crucial, but widely neglected part of plant winter survival.
Max Planck Institute of Molecular Plant Physiology, Am Muhlenberg, Potsdam, Germany.; Department of Chemistry and Bioscience, Aalborg University, Fredrik Bajers Vej, Aalborg East, Denmark.
Temperate and boreal plants show natural low temperature acclimation during autumn. This cold acclimation process results in increased freezing tolerance. Global climate change is leading to increasing spring and autumn temperatures that can trigger deacclimation and loss of freezing tolerance, making plants susceptible to both late-autumn and late-spring freezing events. In particular, spring frosts can have devastating effects on whole ecosystems and can significantly reduce the yield of crop plants. Although the timing and speed of deacclimation are clearly of crucial importance for plant winter survival, the molecular basis of this process is still largely unknown. The regulation of deacclimation is, however, not only related to freezing tolerance, but also to the termination of dormancy, and the initiation of growth and development. In this paper, we provide an overview of what is known about deacclimation in both woody and herbaceous plants. We use publicly available transcriptome data to identify a core set of deacclimation-related genes in Arabidopsis thaliana that highlight physiological determinants of deacclimation, and suggest important directions for future research in this area.
PMID: 31087096
Int J Mol Sci , IF:4.556 , 2019 Sep , V20 (18) doi: 10.3390/ijms20184519
Chemical and Transcriptomic Analysis of Cuticle Lipids under Cold Stress in Thellungiella salsuginea.
College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China. hejunqing@muc.edu.cn.; College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China. tangshuai@muc.edu.cn.; College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China. yangdi@muc.edu.cn.; College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China. chenyue@muc.edu.cn.; College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China. lingludi@muc.edu.cn.; College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China. zouyanli@muc.edu.cn.; College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China. zhouminqi@muc.edu.cn.; College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China. xuxiaojing@muc.edu.cn.
Plant cuticle lipids form outer protective layers to resist environmental stresses; however, the relationship between cuticle properties and cold tolerance is unclear. Here, the extremophyte Thellungiella salsuginea was stressed under cold conditions (4 degrees C) and the cuticle of rosette leaves was examined in terms of epicuticular wax crystal morphology, chemical composition, and cuticle-associated gene expression. The results show that cold induced formation of distinct lamellas within the cuticle ultrastructure. Cold stress caused 14.58% and 12.04% increases in the amount of total waxes and cutin monomer per unit of leaf area, respectively, probably associated with the increase in total fatty acids. The transcriptomic analysis was performed on rosette leaves of Thellungiella exposed to cold for 24 h. We analyzed the expression of 72 genes putatively involved in cuticle lipid metabolism, some of which were validated by qRT-PCR (quantitative reverse transcription PCR) after both 24 h and one week of cold exposure. Most cuticle-associated genes exhibited higher expression levels under cold conditions, and some key genes increased more dramatically over the one week than after just 24 h, which could be associated with increased amounts of some cuticle components. These results demonstrate that the cuticle provides some aspects of cold adaptation in T. salsuginea.
PMID: 31547275
Theor Appl Genet , IF:4.439 , 2019 Sep , V132 (9) : P2591-2604 doi: 10.1007/s00122-019-03373-6
Application of image-based phenotyping tools to identify QTL for in-field winter survival of winter wheat (Triticum aestivum L.).
Department of Plant Agriculture, University of Guelph, 50 Stone Road East, Guelph, ON, N1G 2W1, Canada. ychen53@uoguelph.ca.; Department of Plant Agriculture, University of Guelph, 50 Stone Road East, Guelph, ON, N1G 2W1, Canada.; Centre de recherche sur les grains (CEROM), 740 Chemin Trudeau, Saint-Mathieu-de-Beloeil, QC, J3G 0E2, Canada.; Crop Development Centre, University of Saskatchewan, 51 Campus Drive, Saskatoon, SK, S7N 5A8, Canada.
KEY MESSAGE: Genome-wide association on winter survival was conducted using data from image-based phenotyping method. Nine QTL were observed and three of them with candidate gene identified. Winter survival is an essential trait of winter wheat (Triticum aestivum L.) grown in regions with high risk of winterkill. We characterized a diversity panel of 450 Canadian wheat varieties that included mostly winter-growth habit wheats to identify key genetic factors that contribute to higher winter survival under field conditions. To more accurately quantify winter survival differences among varieties, image-based phenotyping methods, captured by unmanned aerial vehicle (UAV) and on ground level, were used to estimate the winter survival of each varieties. Winter survival index was developed to correct for emergence when evaluating winter survival. Winter survival measurement estimated by visual estimation, UAV imagery and ground imagery showed strong correlation with each other and had comparable broad-sense heritability. Genome-wide association studies resulted in the identification of seven quantitative trait loci (QTL) for winter survival including Vrn-A1. By using the recently released annotated sequence of the wheat genome and the available RNA-Seq data, two putative candidate genes underlying the QTL for winter survival were identified. However, our study showed that certain QTL was unique to specific winter survival measurement. Collectively, our study demonstrated the feasibility of using UAV-based imagery for the identification of loci associated with winter survival in wheat. The complexity of in-field condition make our result a valuable complement to indoor frost-tolerance studies in the identification of genetic factors not directly linked to freezing tolerance.
PMID: 31177292
Microorganisms , IF:4.152 , 2019 Sep , V7 (9) doi: 10.3390/microorganisms7090337
Genetic Screening and Expression Analysis of Psychrophilic Bacillus spp. Reveal Their Potential to Alleviate Cold Stress and Modulate Phytohormones in Wheat.
Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China. zubair_biotech@yahoo.com.; Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China.; Department of Plant Pathology, University of Agriculture, Faisalabad P.O. Box 38040, Pakistan.; Institute of Microbiology, School of life sciences, Lanzhou University, Lanzhou 730000, China.; Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China. gaoxw@njau.edu.cn.
Abiotic stress in plants pose a major threat to cereal crop production worldwide and cold stress is also notorious for causing a decrease in plant growth and yield in wheat. The present study was designed to alleviate cold stress on plants by inoculating psychrophilic PGPR bacteria belonging to Bacillus genera isolated from extreme rhizospheric environments of Qinghai-Tibetan plateau. The genetic screening of psychrophilic Bacillus spp. CJCL2, RJGP41 and temperate B. velezensis FZB42 revealed presence of genetic features corresponding to cold stress response, membrane transport, signal transduction and osmotic regulation. Subsequently, the time frame study for the expression of genes involved in these pathways was also significantly higher in psychrophilic strains as analyzed through qPCR analysis at 4 . The inoculated cold tolerant Bacillus strains also aided in inducing stress response in wheat by regulating abscisic acid, lipid peroxidation and proline accumulation pathways in a beneficial manner. Moreover, during comparative analysis of growth promotion in wheat all three Bacillus strains showed significant results at 25 . Whereas, psychrophilic Bacillus strains CJCL2 and RJGP41 were able to positively regulate the expression of phytohormones leading to significant improvement in plant growth under cold stress.
PMID: 31510075
Physiol Plant , IF:4.148 , 2019 Sep , V167 (1) : P111-126 doi: 10.1111/ppl.12873
Cold deacclimation mechanisms and reacclimation potential in flower buds of blackcurrant (Ribes nigrum).
Department of Food Science, Aarhus University, DK-5792, Aarslev, Denmark.; Department of Chemistry and Bioscience, Aalborg University, DK-9220, Aalborg East, Denmark.
As a consequence of global climate change, cold acclimation and deacclimation cycles are becoming increasingly frequent during winter in temperate regions. However, little is known about plant deacclimation and in particular reacclimation mechanisms, although deacclimation resistance and the ability to reacclimate may have wide-ranging consequences regarding plant productivity in a changing climate. Here, we report time-dependent responses of freezing tolerance, respiration rates, metabolite contents (high-resolution magic angle spinning NMR) and fatty acid levels (gas chromatography) in flower buds of two ecodormant Ribes nigrum cultivars exposed to three different deacclimation temperatures followed by a reacclimation treatment at 4 degrees C. The data reveal that despite differences in the progression of deacclimation, the capacity of blackcurrant flower buds to reharden in late winter is virtually non-existing, implying that increasingly irregular temperature patterns is critical for blackcurrant fruit yield. The early phase of deacclimation is associated with a transient increase in respiration and decreasing contents of amino acids, tricarboxylic acid (TCA) cycle intermediates and sugars, indicating an increased need for carbon sources and respiratory energy production for the activation of growth. Decreasing sugar levels may additionally cause loss of freezing tolerance. Deacclimation also involves desaturation of membrane lipids, which likely also contributes to decreased freezing tolerance but may also reflect biosynthesis of signaling molecules stimulating growth and floral organ differentiation. These data provide new insights into the under-researched deacclimation mechanisms and the ability of blackcurrant to reacclimate following different advancements of deacclimation and contribute to our understanding of plant responses to increasingly irregular temperature patterns.
PMID: 30421426
Sci Rep , IF:3.998 , 2019 Sep , V9 (1) : P13818 doi: 10.1038/s41598-019-49812-8
Mining MYB transcription factors from the genomes of orchids (Phalaenopsis and Dendrobium) and characterization of an orchid R2R3-MYB gene involved in water-soluble polysaccharide biosynthesis.
Key Laboratory of South China Agricultural Plant Molecular Analysis and Gene Improvement, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, China.; P. O. Box 7, Miki-cho post office, Ikenobe 3011-2, Miki-cho, Kita-gun, Kagawa-ken, 761-0799, Japan.; University of the Chinese Academy of Sciences, Beijing, 100049, China.; Biodata Biotechnology Co. Ltd, Heifei, 230031, China.; College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, 510642, China.; Key Laboratory of South China Agricultural Plant Molecular Analysis and Gene Improvement, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, China. duanj@scib.ac.cn.
Members of the MYB superfamily act as regulators in a wide range of biological processes in plants. Despite this, the MYB superfamily from the Orchidaceae has not been identified, and MYB genes related to bioactive water-soluble polysaccharide (WSP) biosynthesis are relatively unknown. In this study, we identified 159 and 165 MYB genes from two orchids, Phalaenopsis equestris and Dendrobium officinale, respectively. The MYB proteins were classified into four MYB classes in both orchids: MYB-related (MYBR), R2R3-MYB, 3R-MYB and atypical MYB proteins. The MYBR proteins in both orchids were classified into five subfamilies and 12 genes were strongly up-regulated in response to cold stress in D. officinale. The R2R3-MYB proteins were both divided into 31 clades in P. equestris and D. officinale. Among these clades, nine contained MYB TFs related to secondary cell wall biosynthesis or testa mucilage biosynthesis in Arabidopsis thaliana. In D. officinale, 10 candidate genes showed an expression pattern corresponding to changes in the WSP content. Overexpression of one of these candidate genes (DoMYB75) in A. thaliana increased seed WSP content by about 14%. This study provides information about MYB genes in two orchids that will further help to understand the transcriptional regulation of WSP biosynthesis in these orchids as well as other plant species.
PMID: 31554868
Sci Rep , IF:3.998 , 2019 Sep , V9 (1) : P13133 doi: 10.1038/s41598-019-49446-w
De novo transcriptome provides insights into the growth behaviour and resveratrol and trans-stilbenes biosynthesis in Dactylorhiza hatagirea - An endangered alpine terrestrial orchid of western Himalaya.
Division of Biotechnology, CSIR-Institute of Himalayan Bioresource Technology, Palampur, 176061, H.P., India.; Academy of Scientific and Innovative Research(AcSIR), CSIR-Institute of Himalayan Bio-Resource Technology, Palampur, 176061, Himachal Pradesh, India.; Division of Biotechnology, CSIR-Institute of Himalayan Bioresource Technology, Palampur, 176061, H.P., India. ravish@ihbt.res.in.; Academy of Scientific and Innovative Research(AcSIR), CSIR-Institute of Himalayan Bio-Resource Technology, Palampur, 176061, Himachal Pradesh, India. ravish@ihbt.res.in.; Division of Biotechnology, CSIR-Institute of Himalayan Bioresource Technology, Palampur, 176061, H.P., India. amitabhatta@ihbt.res.in.; Academy of Scientific and Innovative Research(AcSIR), CSIR-Institute of Himalayan Bio-Resource Technology, Palampur, 176061, Himachal Pradesh, India. amitabhatta@ihbt.res.in.
This is the first report on de novo transcriptome of Dactylorhiza hatagirea, a critically-endangered, terrestrial orchid of alpine Himalayas. The plant is acclaimed for medicinal properties but little is known about its secondary-metabolites profile or cues regulating their biosynthesis. De novo transcriptome analysis was therefore, undertaken to gain basic understanding on these aspects, while circumventing the acute limitation of plant material availability. 65,384 transcripts and finally, 37,371 unigenes were assembled de novo from a total of 236 million reads obtained from shoot, tuber and leaves of the plant. Dominance of differentially-expressing-genes (DEGs) related to cold-stress-response and plant-hormone-signal-transduction; and those involved in photosynthesis, sugar-metabolism and secondary-metabolite-synthesis provided insights into carbohydrate-partitioning in the plant during its preparation for freezing winter at natural habitat. DEGs of glucomannan, ascorbic acid, carotenoids, phylloquinone/naphthoquinones, indole alkaloids, resveratrol and stilbene biosynthesis revealed the secondary-metabolite profile of D. hatagirea. UHPLC results confirmed appreciable amounts of resveratrol and trans-stilbene in D. hatagirea tubers, for the first time. Expression analysis of 15 selected genes including those of phenylpropanoid pathway confirmed the validity of RNA-seq data. Opportunistic growth, temperature- and tissue-specific-differential-expression of secondary metabolite biosynthesis and stress tolerant genes were confirmed using clonal plants growing at 8, 15 and 25 degrees C.
PMID: 31511556
Plant Physiol Biochem , IF:3.72 , 2019 Sep , V142 : P490-499 doi: 10.1016/j.plaphy.2019.08.007
DlICE1, a stress-responsive gene from Dimocarpus longan, enhances cold tolerance in transgenic Arabidopsis.
State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/ Guangdong litchi Engineering Research Center, College of Horticulture, South China Agricultural University, Guangzhou, China.; State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/ Guangdong litchi Engineering Research Center, College of Horticulture, South China Agricultural University, Guangzhou, China. Electronic address: fujiaxin@scau.edu.cn.; State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/ Guangdong litchi Engineering Research Center, College of Horticulture, South China Agricultural University, Guangzhou, China. Electronic address: cmliu@scau.edu.cn.
ICE1 (inducer of CBF expression 1) encodes a typical MYC-like basic helix-loop- helix (bHLH) transcription factor that acts as a pivotal component in the cold signalling pathway. In this study, DlICE1, a novel ICE1-like gene, was isolated from the southern subtropical fruit tree longan (Dimocarpus longan Lour.). DlICE1 encodes a nuclear protein with a highly conserved bHLH domain. DlICE1 expression was slightly upregulated under cold stress. Overexpression of DlICE1 in Arabidopsis conferred enhanced cold tolerance via increased proline content, decreased ion leakage, and reduced malondialdehyde (MDA) and reactive oxygen species (ROS) accumulation. Expression of the ICE1-CBF cold signalling pathway genes, including AtCBF1/2/3 and cold-responsive genes (AtRD29A, AtCOR15A, AtCOR47 and AtKIN1), was also significantly higher in DlICE1-overexpressing lines than in wild-type (WT) plants under cold stress. In conclusion, these findings indicate that DlICE1 is a member of the bHLH gene family and positively regulates cold tolerance in D. longan.
PMID: 31442880
Plant Physiol Biochem , IF:3.72 , 2019 Sep , V142 : P452-459 doi: 10.1016/j.plaphy.2019.07.026
Membrane sterols and genes of sterol biosynthesis are involved in the response of Triticum aestivum seedlings to cold stress.
Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Center of RAS, P.O. Box 30, Kazan, 420111, Russia. Electronic address: yulavalitova@mail.ru.; Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Center of RAS, P.O. Box 30, Kazan, 420111, Russia. Electronic address: sulkarnayeva@gmail.com.; Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Center of RAS, P.O. Box 30, Kazan, 420111, Russia. Electronic address: fmukhitova@mail.ru.; Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Center of RAS, P.O. Box 30, Kazan, 420111, Russia. Electronic address: s_dmitrieva@list.ru.; School of Life Sciences, University of KwaZulu-Natal, Private Bag X01, Scottsville, 3209, South Africa. Electronic address: rpbeckett@gmail.com.; Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Center of RAS, P.O. Box 30, Kazan, 420111, Russia; Kazan (Volga Region) Federal University, Kremlevskaya Str 18, Kazan, 420008, Russia. Electronic address: minibayeva@kibb.knc.ru.
Cold stress can significantly alter the composition and functioning of the major membrane lipids in plants. However, the roles of the sterol component of plant membranes in stress tolerance remain unclear. In the work presented here we investigated the role of sterols in the response of wheat to cold stress. Initial experiments demonstrated that the roots and leaves of wheat seedlings are differentially sensitive to low positive temperatures. In the roots, cold stress induced disturbance of membrane integrity and accumulation of ROS followed by the induction of autophagy. The absence of such changes in leaves suggests that in wheat, the roots are more sensitive to cold than the leaves. The roots display a time-dependent parabolic pattern of cold stress response, characterized by raised levels of sterols and markers of oxidative stress during short-term treatment, and a decline of these parameters after prolonged treatment. MbetaCD-induced sterol depletion aggravated the negative effects of cold on the roots. In the leaves the changes also displayed parabolic patterns, with significant changes occurring in 24-ethyl sterols and major PLs. Constitutively high levels of sterols, glycolipids and PLs, and up-regulation of TaSMTs in the leaves may provide membrane stability and cold tolerance. Taken together, results suggest that sterols play important roles in the response of wheat seedlings to cold stress.
PMID: 31421442
Plant Physiol Biochem , IF:3.72 , 2019 Sep , V142 : P254-262 doi: 10.1016/j.plaphy.2019.07.017
A tomato transcription factor, SlDREB3 enhances the tolerance to chilling in transgenic tomato.
College of Biological Science, Jining Medical University, Ri'zhao, Shandong, 276800, PR China. Electronic address: gdwang@mail.jnmc.edu.cn.; College of Biological Science, Jining Medical University, Ri'zhao, Shandong, 276800, PR China.; College of Life Science, Nanjing University, Nan'jing, Jiangshu, 210046, PR China. Electronic address: ghcai2008@163.com.
The dehydration response factor (DREB) transcription factor (TF) family can function in response to multiple cues around environment in plants. Nevertheless, the functions of dehydration response factor (DREB protein) in plant cold tolerance, especially in tomatoes (Solanum lycopersicum), have been rarely studied. In this study, the functions of tomato DREB TF (SlDREB3) in cold resistance were studied using transgenic tomatoes. The level of transcripts revealed that SlDREB3 was triggered by H2O2 and 4 degrees C treatments, indicating that SlDREB3 participates in response to cold stress in plants. SlDREB3-overexpressing plants exhibited high fresh mass, chlorophyll content, Fv/Fm, and O2-evolving activity; low membrane damage; and reactive oxygen species accumulation under chilling stress. Furthermore, the high expression levels of late embryogenesis-abundant genes SlLEA9 and SlLEA26 were detected in transgenic plants in response to cold stress. These findings revealed that SlDREB3 overexpression improved the tolerance to cold stress in transgenic plants possibly by upregulating SlLEAs expression.
PMID: 31326718
Plant Physiol Biochem , IF:3.72 , 2019 Sep , V142 : P94-105 doi: 10.1016/j.plaphy.2019.05.034
Evaluation, characterization, expression profiling, and functional analysis of DXS and DXR genes of Populus trichocarpa.
Co-Innovation Center for Sustainable Forestry in Southern China, Key Laboratory of Forest Genetics & Biotechnology, Ministry of Education, Nanjing Forestry University. Nanjing, 210037, China; Nanjing Key Laboratory of Quality and Safety of Agricultural Products, Nanjing Xiaozhuang University, Nanjing, 211171, China.; Co-Innovation Center for Sustainable Forestry in Southern China, Key Laboratory of Forest Genetics & Biotechnology, Ministry of Education, Nanjing Forestry University. Nanjing, 210037, China.; Co-Innovation Center for Sustainable Forestry in Southern China, Key Laboratory of Forest Genetics & Biotechnology, Ministry of Education, Nanjing Forestry University. Nanjing, 210037, China. Electronic address: qzhuge@njfu.edu.cn.
1-Deoxy-D-xylulose-5-phosphate synthasse (DXS) and 1-deoxy-D-xylulose-5-phosphate reductoisomerase (DXR) are key enzymes in terpenoid biosynthesis. DXS catalyzes the formation of 1-deoxy-D-xylulose 5-phosphate (DXP) from pyruvate and D-glyceraldehyde-3-phosphate. DXR catalyzes the formation of 2-C-methyl-D-erythritol 4-phosphate (MEP) from DXP. Previous studies of the DXS and DXR genes have focused on herbs, such as Arabidopsis thaliana, Salvia miltiorrhiza, and Amomum villosum, but few studies have been conducted on woody plants. For that reason, we chose Populus trichocarpa as a model woody plant for investigating the DXS and DXR genes. PtDXS exhibited the highest expression level in leaves and the lowest expression in roots. PtDXR showed maximum expression in young leaves, and the lowest expression in mature leaves. The expression profiles revealed by RT-PCR following different elicitor treatments such as abscisic acid, NaCl, PEG6000, H2O2, and cold stress showed that PtDXS and PtDXR were elicitor-responsive genes. Our results showed that the PtDXS gene exhibited diurnal changes, but PtDXR did not. Moreover, overexpression of PtDXR in transgenic poplars improved tolerance to abiotic and biotic stresses. Those results showed that the PtDXR encoded a functional protein, and widely participates in plant growth and development, stress physiological process.
PMID: 31279136
Tree Physiol , IF:3.655 , 2019 Sep , V39 (9) : P1583-1599 doi: 10.1093/treephys/tpz059
Transcriptomic and metabolomic profiling of Camellia sinensis L. cv. 'Suchazao' exposed to temperature stresses reveals modification in protein synthesis and photosynthetic and anthocyanin biosynthetic pathways.
College of Horticulture, Nanjing Agricultural University, Nanjing, P. R. China.; Forestry and Pomology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, P. R. China.; Qingdao Technical College, Qingdao, P. R. China.
To determine the mechanisms in tea plants responding to temperature stresses (heat and cold), we examined the global transcriptomic and metabolomic profiles of the tea plant cultivar 'Suchazao' under moderately low temperature stress (ML), severely low temperature stress (SL), moderately high temperature stress (MH) and severely high temperature stress (SH) using RNA-seq and high performance liquid chromatography tandem mass spectrometry/mass spectrometry (HPLC-MS/MS), respectively. The identified differentially expressed genes indicated that the synthesis of stress-resistance protein might be redirected to cope with the temperature stresses. We found that heat shock protein genes Hsp90 and Hsp70 played more critical roles in tea plants in adapting to thermal stress than cold, while late embryogenesis abundant protein genes (LEA) played a greater role under cold than heat stress, more types of zinc finger genes were induced under cold stress as well. In addition, energy metabolisms were inhibited by SH, SL and ML. Furthermore, the mechanisms of anthocyanin synthesis were different under the cold and heat stresses. Indeed, the CsUGT75C1 gene, encoding UDP-glucose:anthocyanin 5-O-glucosyl transferase, was up-regulated in the SL-treated leaves but down-regulated in SH. Metabolomics analysis also showed that anthocyanin monomer levels increased under SL. These results indicate that the tea plants share certain foundational mechanisms to adjust to both cold and heat stresses. They also developed some specific mechanisms for surviving the cold or heat stresses. Our study provides effective information about the different mechanisms tea plants employ in surviving cold and heat stresses, as well as the different mechanisms of anthocyanin synthesis, which could speed up the genetic breeding of heat- and cold-tolerant tea varieties.
PMID: 31135909
Plants (Basel) , IF:2.762 , 2019 Sep , V8 (10) doi: 10.3390/plants8100378
Ecophysiological Plasticity and Cold Stress Adaptation in Himalayan Alpine Herbs: Bistorta affinis and Sibbaldia procumbens.
Department of Botany, Hazara University, Mansehra-21300, KP, Pakistan. irahman@mobot.org.; William L. Brown Center, Missouri Botanical Garden, 4344 Shaw Blvd., P.O. Box 299, St. Louis, MO 63110, USA. irahman@mobot.org.; William L. Brown Center, Missouri Botanical Garden, 4344 Shaw Blvd., P.O. Box 299, St. Louis, MO 63110, USA. Robbie.hart@mobot.org.; Department of Botany, Hazara University, Mansehra-21300, KP, Pakistan. draftab@hu.edu.pk.; Department of Botany, Hazara University, Mansehra-21300, KP, Pakistan. zafariqbal@hu.edu.pk.; Department of Plant Production, College of Food and Agriculture Science, King Saud University, Riyadh 11451, Saudi Arabia. alqarawi@ksu.edu.sa.; Department of Plant Production, College of Food and Agriculture Science, King Saud University, Riyadh 11451, Saudi Arabia.; Botany and Microbiology Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia. habeer@ksu.edu.sa.; Mycology and Plant Disease Survey Department, Plant Pathology Research Institute, Agriculture Research Center, Giza 12619, Egypt. habeer@ksu.edu.sa.; Department of Botany, Hazara University, Mansehra-21300, KP, Pakistan. fbotany@yahoo.com.; Department of Botany, Hazara University, Mansehra-21300, KP, Pakistan. niaz@hu.edu.pk.; Department of Biology, University of Sao Paolo, SP 05315-970, Brazil. calixtos.edu@usp.br.; Department of Biology, University of Missouri, St. Louis, MO 63166-0299, USA. calixtos.edu@usp.br.
Plants have evolved several metabolic pathways as a response to environmental stressors such as low temperatures. In this perspective, it is paramount to highlight physiological mechanisms of plant responses to altitudinal gradients as a proxy to evaluate changing environments. Here, we aimed to determine the impact of elevation on the physiological attributes of two plant species along an altitudinal gradient. Our hypothesis was that the altitudinal gradient influences proline, protein, and sugar contents, as well as abscisic acid (ABA) and indole acetic acid (IAA) concentrations. We studied these physiological components in leaves collected from four different altitudinal ranges in Himalayan region of Pakistan from two native herbs, namely Bistorta affinis and Sibbaldia procumbens. Leaves were collected at the initial blooming phase from each altitudinal range, viz. 2850 m, 3250 m, 3750 m and 4250 m. We observed that most abiotic factors decrease with altitude which induces cold acclimation. A significant increase in the concentration of physiological components was observed as altitude increased, except for IAA, which decreased. Furthermore, we did not find variations in proline, ABA and IAA concentrations between species; only sugar and protein, with higher values for B. affinis. We conclude that altitudinal gradients significantly affect the physiological components of B. affinis and S. procumbens in Himalayan region. This result contributes to the understanding of how plants adapt to environmental pressures, acting as a proxy for the evaluation of impacts caused by climate changes.
PMID: 31569761
Bot Stud , IF:2.163 , 2019 Sep , V60 (1) : P22 doi: 10.1186/s40529-019-0268-8
Construction of gene causal regulatory networks using microarray data with the coefficient of intrinsic dependence.
Department of Agronomy, National Taiwan University, Taipei, 106, Taiwan. lyliu@ntu.edu.tw.; Department of Agronomy, National Taiwan University, Taipei, 106, Taiwan.; Department of Horticulture and Landscape Architecture, National Taiwan University, Taipei, 106, Taiwan.
BACKGROUND: In the past two decades, biologists have been able to identify the gene signatures associated with various phenotypes through the monitoring of gene expressions with high-throughput biotechnologies. These gene signatures have in turn been successfully applied to drug development, disease prevention, crop improvement, etc. However, ignoring the interactions among genes has weakened the predictive power of gene signatures in practical applications. Gene regulatory networks, in which genes are represented by nodes and the associations between genes are represented by edges, are typically constructed to analyze and visualize such gene interactions. More specifically, the present study sought to measure gene-gene associations by using the coefficient of intrinsic dependence (CID) to capture more nonlinear as well as cause-effect gene relationships. RESULTS: A stepwise procedure using the CID along with the partial coefficient of intrinsic dependence (pCID) was demonstrated for the rebuilding of simulated networks and the well-known CBF-COR pathway under cold stress using Arabidopsis microarray data. The procedure was also applied to the construction of bHLH gene regulatory pathways under abiotic stresses using rice microarray data, in which OsbHLH104, a putative phytochrome-interacting factor (OsPIF14), and OsbHLH060, a positive regulator of iron homeostasis (OsPRI1) were inferred as the most affiliated genes. The inferred regulatory pathways were verified through literature reviews. CONCLUSIONS: The proposed method can efficiently decipher gene regulatory pathways and may assist in achieving higher predictive power in practical applications. The lack of any mention in the literature of some of the regulatory event may have been due to the high complexity of the regulatory systems in the plant transcription, a possibility which could potentially be confirmed in the near future given ongoing rapid developments in bio-technology.
PMID: 31512008
Genome , IF:2.037 , 2019 Sep , V62 (9) : P635-642 doi: 10.1139/gen-2019-0015
Identification of microRNAs responding to cold stress in Dongxiang common wild rice.
National Center for Evaluation of Agricultural Wild Plants (Rice), MOE Laboratory of Crop Heterosis and Utilization, Beijing Key Laboratory of Crop Genetic Improvement, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, China.
Low temperature is a vital effector of rice at different growth stages. MicroRNAs (miRNAs) play important roles in responding to abiotic and biotic stresses. Here, we confirmed the cold tolerance of Dongxiang common wild rice and explored the miRNAs differentially expressed under cold stress using genome-wide small RNA sequencing. In total, 16 miRNAs, nine upregulated and seven downregulated by cold stress, were characterized in Dongxiang common wild rice, and their target genes were predicted. Additionally, an AgriGO analysis of the target genes revealed that they were enriched in several terms related to cold-stress tolerance, suggesting a complex response mechanism, involving miRNAs, to cold stress in Dongxiang common wild rice.
PMID: 31283885
3 Biotech , IF:1.798 , 2019 Sep , V9 (9) : P335 doi: 10.1007/s13205-019-1859-5
The role of antifreeze proteins in the regulation of genes involved in the response of Hosta capitata to cold.
1Department of Horticulture and Life Science, Yeungnam University, Geyongsan, South Korea.0000 0001 0674 4447grid.413028.c; 2Department of Horticulture, Yezin Agricultural University, Nay Pyi Taw, Myanmar.grid.444661.5; 3Department of Horticultural Science, Kyungpook National University, Daegu, South Korea.0000 0001 0661 1556grid.258803.4; 4Department of Agricultural Education, Sunchon National University, Suncheon, South Korea.0000 0000 8543 5345grid.412871.9
Cold temperatures are a major source of stress for plants and negatively impact crop yield. A possible way to protect plants is to treat them with antifreeze proteins (AFPs). Here, we investigated whether fish AFPs can shield the rare ornamental species Hosta capitata from low-temperature stress. We elucidated the expression patterns of the cold-inducible genes C-repeat binding factor 1 (CBF1) and dehydrin 1 (DHN1), as well as the antioxidant genes superoxide dismutase (SOD) and catalase (CAT). All were upregulated at low temperature (4 degrees C). With increasing exposure time, CBF1 and DHN1 expression generally rose (except CBF1 at 48 h). In contrast, SOD and CAT expression gradually declined from 6 to 48 h. Depending on exposure duration, AFP regulation of gene transcription varied with concentration. However, compared with other concentrations, 100 microg/L AFP reduced CBF1 and DHN1 expression and increased SOD and CAT expression in plants, regardless of exposure time. Both AFP I and III were likely to be most effective at protecting plants against cold stress at concentrations of 100 microg/L. Their involvement in H. capitata cold-stress treatment occurred through regulating the expression of important stress-response genes.
PMID: 31475087