Nat Commun , IF:12.121 , 2020 Mar , V11 (1) : P1560 doi: 10.1038/s41467-020-15311-y
Housing temperature influences exercise training adaptations in mice.
Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, 2100, Denmark.; Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, 2200, Denmark.; Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Frederiksberg, 1871, Denmark.; Department of Food Science, Faculty of Science, University of Copenhagen, Frederiksberg, 1958, Denmark.; Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, 2100, Denmark. Erichter@nexs.ku.dk.; Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, 2100, Denmark. Lshansen@nexs.ku.dk.
Exercise training is a powerful means to combat metabolic diseases. Mice are extensively used to investigate the benefits of exercise, but mild cold stress induced by ambient housing temperatures may confound translation to humans. Thermoneutral housing is a strategy to make mice more metabolically similar to humans but its effects on exercise adaptations are unknown. Here we show that thermoneutral housing blunts exercise-induced improvements in insulin action in muscle and adipose tissue and reduces the effects of training on energy expenditure, body composition, and muscle and adipose tissue protein expressions. Thus, many reported effects of exercise training in mice are likely secondary to metabolic stress of ambient housing temperature, making it challenging to translate to humans. We conclude that adaptations to exercise training in mice critically depend upon housing temperature. Our findings underscore housing temperature as a critical parameter in the design and interpretation of murine exercise training studies.
PMID: 32214091
New Phytol , IF:8.512 , 2020 Mar , V225 (6) : P2453-2467 doi: 10.1111/nph.16324
Cyclophilin OsCYP20-2 with a novel variant integrates defense and cell elongation for chilling response in rice.
Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.; University of Chinese Academy of Sciences, Beijing, 100049, China.; Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, 100101, China.; The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Sciences, Shandong University, Jinan, 250100, China.; Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.; Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA.; State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310006, China.
Coordinating stress defense and plant growth is a survival strategy for adaptation to different environments that contains a series of processes, such as, cell growth, division and differentiation. However, little is known about the coordination mechanism for protein conformation change. A cyclophilin OsCYP20-2 with a variant interacts with SLENDER RICE1 (SLR1) and OsFSD2 in the nucleus and chloroplasts, respectively, to integrate chilling tolerance and cell elongation in rice (Oryza sativa) (FSD2, Fe-superoxide dismutase 2). Mass spectrum assay showed that OsNuCYP20-2 localized at the nucleus (nuclear located OsCYP20-2) was a new variant of OsCYP20-2 that truncated 71 amino-acid residues in N-terminal. The loss-of function OsCYP20-2 mutant showed sensitivity to chilling stress with accumulation of extra reactive oxygen species (ROS). In chloroplasts, the full-length OsCYP20-2 promotes OsFSD2 forming homodimers which enhance its activity, eliminating the accumulation of ROS under chilling stress. However, the mutant had shorter epidermal cells in comparison with wild-type Hwayoung (HY). In the nucleus, OsCYP20-2 caused conformation change of SLR1 to promote its degradation for cell elongation. Our data reveal a cyclophilin with a variant with dual-localization in chloroplasts and the nucleus, which mediate chilling tolerance and cell elongation.
PMID: 31736073
Plant Physiol , IF:6.902 , 2020 Mar , V182 (3) : P1239-1255 doi: 10.1104/pp.19.00947
Identification of Chloroplast Envelope Proteins with Critical Importance for Cold Acclimation.
Technische Universitat Kaiserslautern, Department of Biology, Plant Physiology, 67653 Kaiserslautern, Germany.; Technische Universitat Kaiserslautern, Department of Biology, Computational Systems Biology, 67653 Kaiserslautern, Germany.; Technische Universitat Kaiserslautern, Department of Biology, Molecular Biotechnology and Systems Biology, 67653 Kaiserslautern, Germany.; Technische Universitat Kaiserslautern, Department of Biology, Plant Physiology, 67653 Kaiserslautern, Germany neuhaus@rhrk.uni-kl.de.
The ability of plants to withstand cold temperatures relies on their photosynthetic activity. Thus, the chloroplast is of utmost importance for cold acclimation and acquisition of freezing tolerance. During cold acclimation, the properties of the chloroplast change markedly. To provide the most comprehensive view of the protein repertoire of the chloroplast envelope, we analyzed this membrane system in Arabidopsis (Arabidopsis thaliana) using mass spectrometry-based proteomics. Profiling chloroplast envelope membranes was achieved by a cross comparison of protein intensities across the plastid and the enriched membrane fraction under both normal and cold conditions. We used multivariable logistic regression to model the probabilities for the classification of an envelope localization. In total, we identified 38 envelope membrane intrinsic or associated proteins exhibiting altered abundance after cold acclimation. These proteins comprise several solute carriers, such as the ATP/ADP antiporter nucleotide transporter2 (NTT2; substantially increased abundance) or the maltose exporter MEX1 (substantially decreased abundance). Remarkably, analysis of the frost recovery of ntt loss-of-function and mex1 overexpressor mutants confirmed that the comparative proteome is well suited to identify key factors involved in cold acclimation and acquisition of freezing tolerance. Moreover, for proteins with known physiological function, we propose scenarios explaining their possible roles in cold acclimation. Furthermore, spatial proteomics introduces an additional layer of complexity and enables the identification of proteins differentially localized at the envelope membrane under the changing environmental regime.
PMID: 31932409
Sci Total Environ , IF:6.551 , 2020 Mar , V706 : P135714 doi: 10.1016/j.scitotenv.2019.135714
Response of plant physiological attributes to altitudinal gradient: Plant adaptation to temperature variation in the Himalayan region.
Department of Botany, Hazara University, Mansehra 21300, KP, Pakistan; William L. Brown Center, Missouri Botanical Garden, P.O. Box 299, St. Louis, MO 63166-0299, USA. Electronic address: irahman@mobot.org.; Department of Botany, Hazara University, Mansehra 21300, KP, Pakistan. Electronic address: aftabafzalkiani@yahoo.com.; Department of Botany, Hazara University, Mansehra 21300, KP, Pakistan.; William L. Brown Center, Missouri Botanical Garden, P.O. Box 299, St. Louis, MO 63166-0299, USA.; Plant Production Department, College of Food and Agricultural Sciences, King Saud University, P.O. Box. 2460, Riyadh 11451, Saudi Arabia.; Department of Biology, College of Science, Imam Mohammad Ibn Saud Islamic University, Riyadh, Saudi Arabia.; Department of Biology, University of Sao Paolo, SP, Brazil.; Department of Environmental Sciences, International Islamic University, Islamabad, Pakistan.; Department of Biological Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia.; Ilia State University Institute of Botany and Bakuriani Alpine Botanical Garden, Department of Ethnobotany, Botanical Str., 0105 Tbilisi, Georgia.
Plants have evolved several metabolic pathways as a response to environmental stress like low temperatures. In this perspective, it is paramount to highlight physiological mechanisms of plant responses to changing environments. To determine the impact of cold stress on the physiological attributes of high altitude plant natives, i.e. Pedicularis punctata and Plantago major, we studied the protein, sugar and proline contents, as well as abscisic acid (ABA) and indoleacetic acid (IAA) in leaves collected from three different altitudinal ranges in Himalayan region of Pakistan. Leaves were collected at the initial blooming phase from each altitudinal range i.e. 2400-2500 m, 2950-3250 m and 3500-3550 m. Temperature decreases with an increase in the altitude which induces cold acclimation. Both plant species showed significant variation in the concentrations of the ecophysiological attributes evaluated at the different collection altitudes. The concentrations of all compounds except for IAA increased as temperature decreased and altitude increased. IAA showed an opposite response, that is, the concentrations of this phytohormone decreased with decreasing temperature and increasing altitude. We showed that temperature significantly affected the physiological attributes of Pedicularis punctata and Plantago major in the Himalayan region, which works as a proxy for understanding the plant responses to climate change. As per survival and risk assessment, underlying physiological mechanisms of plant response (understory plants) to changing environments (altitude and temperature ranges) revealed adaptation in the chilling environments. Further studies are needed to completely understand how the studied plants photosynthetic characteristics are affected by altitudinal gradient.
PMID: 31940726
Genomics , IF:6.205 , 2020 Mar , V112 (2) : P1128-1138 doi: 10.1016/j.ygeno.2019.06.027
Effects of early cold stress on gene expression in Chlamydomonas reinhardtii.
The Institute for Systems Biology, Jianghan University, Wuhan 430056, China.; School of Information and Communication Engineering, Hubei University of Economics, Wuhan 430205, China. Electronic address: tslnet@163.com.; The Institute for Systems Biology, Jianghan University, Wuhan 430056, China; Department of Computer Science and Engineering, Washington University, St. Louis, MO 36130, USA. Electronic address: weixiong.zhang@wustl.edu.; The Institute for Systems Biology, Jianghan University, Wuhan 430056, China. Electronic address: chenlihong@jhun.edu.cn.
Cold stress imposes a great impact on the growth of nearly all photosynthetic organisms, including Chlamydomonas reinhardtii (C. reinhardtii). Despite prior studies on the mechanism of stress acclimation in plants, little has been done on the early events of cold sensing in C. reinhardtii. Here, we used C. reinhardtii as a model to study early events of cold signal transduction. By analyzing transcriptomic changes of C. reinhardtii exposed to cold, we found that 3471 genes were differentially expressed after 1h of cold exposure. These genes were associated with a wide range of biological events and processes such as protein synthesis, cell cycle and protein kinase-based phosphorylation. Besides, the promoter of one gene (named as crAP2) which belongs to AP2/EREBP family and was significantly induced by cold was cloned, and functional analysis was conducted using GUS activity analysis through Agrobacterium-mediated transient assay in tobacco leaves.
PMID: 31251979
Antioxidants (Basel) , IF:5.014 , 2020 Mar , V9 (3) doi: 10.3390/antiox9030218
Melatonin Mitigates Chilling-Induced Oxidative Stress and Photosynthesis Inhibition in Tomato Plants.
School of Life Sciences, Liaocheng University, Liaocheng 252000, China.; College of Forestry, Northwest A&F University, Yangling 712100, China.
Melatonin has been demonstrated to play a variety of roles in plants. Of particular importance is its role as a potent antioxidative agent. In the present study, we generated melatonin-deficient tomato plants using virus-induced gene silencing (VIGS) approach and melatonin-rich tomato plants by foliar application of melatonin. These tomato plants were used to assess the effect of melatonin on chilling-induced oxidative stress and chilling-induced photosynthesis inhibition. We found that melatonin deficiency increased accumulation of reactive oxygen species (ROS) and aggravated lipid peroxidation in chilling-stressed tomato leaves, while exogenous application of melatonin had the opposite effect. Under chilling stress, melatonin-deficient tomato plants showed impaired antioxidant capacity as evidenced by lower activities of antioxidant enzymes and decreased rations of reduced glutathione (GSH)/oxidized glutathione (GSSG) and reduced ascorbate (AsA)/oxidized ascorbate (DHA), compared with melatonin-rich tomato plants. Furthermore, suppression of melatonin biosynthesis led to more photosynthesis inhibition under the chilling condition and compromised the capability of subsequent photosynthesis recovery in tomato plants. In addition, melatonin-deficient tomato plants displayed less activity of an important Calvin-Benson cycle enzyme sedoheptulose-1,7-bisphosphatase (SBPase) than melatonin-rich tomato plants under chilling stress. Collectively, our data indicate that melatonin is critical for antioxidant capacity and redox balance and is in favor of photosynthesis in tomato plants under chilling stress.
PMID: 32155702
J Integr Plant Biol , IF:4.885 , 2020 Mar , V62 (3) : P258-263 doi: 10.1111/jipb.12918
The transcription factor ICE1 functions in cold stress response by binding to the promoters of CBF and COR genes.
Shanghai Center for Plant Stress Biology and CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 200032, China.; Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN, 47907, USA.; University of the Chinese Academy of Sciences, Beijing, 100049, China.; State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China.; State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China.
A recent paper by Kidokoro et al. (2020) in The Plant Cell reported a transgene-dependent transcriptional silencing phenomenon in the dominant ice1-1 Arabidopsis mutant containing the CBF3-LUC reporter, and questioned whether ICE1 may regulate CBF genes and may be involved in plant cold response. Here, we evaluate available evidence supporting the involvement of ICE1 in plant cold response, and provide ChIP-seq data showing ICE1 binding to the promoters of CBF genes and other regulatory genes known to be critical for cold response as well as to the promoters of some COR genes.
PMID: 32068336
Int J Mol Sci , IF:4.556 , 2020 Mar , V21 (6) doi: 10.3390/ijms21061921
Comparative Transcriptome-Based Mining and Expression Profiling of Transcription Factors Related to Cold Tolerance in Peanut.
Peanut Research Institute, College of Agronomy, Shenyang Agricultural University, Shenyang 110161, China.
Plants tolerate cold stress by regulating gene networks controlling cellular and physiological traits to modify growth and development. Transcription factor (TF)-directed regulation of transcription within these gene networks is key to eliciting appropriate responses. Identifying TFs related to cold tolerance contributes to cold-tolerant crop breeding. In this study, a comparative transcriptome analysis was carried out to investigate global gene expression of entire TFs in two peanut varieties with different cold-tolerant abilities. A total of 87 TF families including 2328 TF genes were identified. Among them, 445 TF genes were significantly differentially expressed in two peanut varieties under cold stress. The TF families represented by the largest numbers of differentially expressed members were bHLH (basic helix-loop-helix protein), C2H2 (Cys2/His2 zinc finger protein), ERF (ethylene-responsive factor), MYB (v-myb avian myeloblastosis viral oncogene homolog), NAC (NAM, ATAF1/2, CUC2) and WRKY TFs. Phylogenetic evolutionary analysis, temporal expression profiling, protein-protein interaction (PPI) network, and functional enrichment of differentially expressed TFs revealed the importance of plant hormone signal transduction and plant-pathogen interaction pathways and their possible mechanism in peanut cold tolerance. This study contributes to a better understanding of the complex mechanism of TFs in response to cold stress in peanut and provides valuable resources for the investigation of evolutionary history and biological functions of peanut TFs genes involved in cold tolerance.
PMID: 32168930
Int J Mol Sci , IF:4.556 , 2020 Mar , V21 (6) doi: 10.3390/ijms21062067
Comparative Transcriptome Analysis Provides Insights into the Seed Germination in Cotton in Response to Chilling Stress.
State Key Laboratory of Cotton Biology, Institute of Cotton Research of CAAS, Anyang, Henan 455000, China.; MOA Key Laboratory of Crop Eco-physiology and Farming system in the Middle Reaches of Yangtze River, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430000, China.
Gossypium hirsutum L., is a widely cultivated cotton species around the world, but its production is seriously threatened by its susceptibility to chilling stress. Low temperature affects its germination, and the underlying molecular mechanisms are rarely known, particularly from a transcriptional perspective. In this study, transcriptomic profiles were analyzed and compared between two cotton varieties, the cold-tolerant variety KN27-3 and susceptible variety XLZ38. A total of 7535 differentially expressed genes (DEGs) were identified. Among them, the transcripts involved in energy metabolism were significantly enriched during germination based on analysis of Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, such as glycolysis/gluconeogenesis, tricarboxylic acid cycle (TCA cycle), and glyoxylate cycle (GAC). Results from further GO enrichment analysis show the earlier appearance of DNA integration, meristem growth, cotyledon morphogenesis, and other biological processes in KN27-3 compared with XLZ38 under chilling conditions. The synthesis of asparagine, GDP-mannose, and trehalose and the catabolic process of raffinose were activated. DEGs encoding antioxidants (spermidine) and antioxidase (CAT1, GPX4, DHAR2, and APX1) were much more up-regulated in embryos of KN27-3. The content of auxin (IAA), cis-zeatin riboside (cZR), and trans-zeatin riboside (tZR) in KN27-3 are higher than that in XLZ38 at five stages (from 12 h to 54 h). GA3 was expressed at a higher level in KN27-3 from 18 h to 54 h post imbibition compared to that in XLZ38. And abscisic acid (ABA) content of KN27-3 is lower than that in XLZ38 at five stages. Results from hormone content measurements and the related gene expression analysis indicated that IAA, CTK, and GA3 may promote germination of the cold-tolerant variety, while ABA inhibits it. These results expand the understanding of cottonseed germination and physiological regulations under chilling conditions by multiple pathways.
PMID: 32197292
Int J Mol Sci , IF:4.556 , 2020 Mar , V21 (6) doi: 10.3390/ijms21061942
Involvement of Salicylic Acid and Other Phenolic Compounds in Light-Dependent Cold Acclimation in Maize.
Agricultural Institute, Centre for Agricultural Research, 2462 Martonvasar, Brunszvik 2, Hungary.
The exposure of plants to non-lethal low temperatures may increase their tolerance to a subsequent severe chilling stress. To some extent, this is also true for cold-sensitive species, including maize. In the present work, based on our previous microarray experiment, the differentially expressed genes with phenylpropanoid pathways in the focus were further investigated in relation to changes in certain phenolic compounds and other plant growth regulators. Phenylalanine ammonia lyase (PAL) was mainly activated under limited light conditions. However, light-induced anthocyanin accumulation occurred both in the leaves and roots. Chilling stress induced the accumulation of salicylic acid (SA), but this accumulation was moderated in the cold-acclimated plants. Acclimation also reduced the accumulation of jasmonic acid (JA) in the leaves, which was rather induced in the roots. The level of abscisic acid (ABA) is mainly related to the level of the stress, and less indicated the level of the acclimation. The highest glutathione (GSH) amount was observed during the recovery period in the leaves of plants that were cold acclimated at growth light, while their precursors started to accumulate GSH even during the chilling. In conclusion, different light conditions during the cold acclimation period differentially affected certain stress-related mechanisms in young maize plants and changes were also light-dependent in the root, not only in the leaves.
PMID: 32178416
Int J Mol Sci , IF:4.556 , 2020 Mar , V21 (6) doi: 10.3390/ijms21062062
Candidate Genes for Freezing and Drought Tolerance Selected on the Basis of Proteome Analysis in Doubled Haploid Lines of Barley.
Department of Plant Breeding, Physiology and Seed Science, University of Agriculture in Krakow, Podluzna 3, 30-239 Krakow, Poland.; The Franciszek Gorski Institute of Plant Physiology, Polish Academy of Sciences, Niezapominajek 21, 30-239 Krakow, Poland.
Plant tolerance to environmental stress is determined by a very complicated network composed of many intra- and extracellular factors. The aim of this study was to select candidate genes involved in responses to freezing and drought in barley on the basis of previous proteomic studies and to analyze changes in their expression caused by application of both stress factors. Six candidate genes for freezing tolerance (namely the genes encoding elongation factor 1 alpha (EF1A), ferredoxin-NADP reductase, a 14-3-3a protein, beta-fructofuranosidase, CBF2A and CBF4B) and six for drought tolerance (encoding transketolase, periplasmic serine protease, triosephosphate isomerase, a protein with a co-chaperon region (GroEs), pfam14200 and actin) were chosen arbitrarily on the basis of in silico bioinformatic analyses. The expression levels of these genes were measured under control and stress conditions in six DH (doubled haploid) lines with differing freezing and drought tolerance. The results of gene expression analysis confirmed the roles of the candidate genes preselected in this study on the basis of previous proteome analysis in contributing to the differences in freezing and drought tolerance observed in the studied population of DH lines of winter barley.
PMID: 32192224
Sci Rep , IF:3.998 , 2020 Mar , V10 (1) : P5242 doi: 10.1038/s41598-020-62111-x
Combined transcriptomic and metabolomic analyses uncover rearranged gene expression and metabolite metabolism in tobacco during cold acclimation.
National Tobacco Cultivation and Physiology and Biochemistry Research Center, College of Tobacco Science, Henan Agricultural University, Zhengzhou, 450002, People's Republic of China.; National Tobacco Cultivation and Physiology and Biochemistry Research Center, College of Tobacco Science, Henan Agricultural University, Zhengzhou, 450002, People's Republic of China. shuhan_jia@163.com.; National Tobacco Cultivation and Physiology and Biochemistry Research Center, College of Tobacco Science, Henan Agricultural University, Zhengzhou, 450002, People's Republic of China. zichengxu@126.com.
Cold temperatures often severely restrict the growth, distribution and productivity of plants. The freezing tolerance of plants from temperate climates can be improved by undergoing periods of cold acclimation (CA). Tobacco is an important economic plant and is sensitive to cold stress. However, the dynamic changes and regulatory mechanisms of gene expression and metabolic processes during CA remain largely unknown. In this study, we performed RNA sequencing and metabolomic profiling analyses to identify the genes and metabolites specifically expressed during CA. Our transcriptomic data revealed 6905 differentially expressed genes (DEGs) during CA. Functional annotation and enrichment analyses revealed that the DEGs were involved mainly in signal transduction, carbohydrate metabolism and phenylpropanoid biosynthesis. Moreover, a total of 35 significantly changed metabolites were identified during CA via an LC-MS platform. Many protective metabolites, such as amino acids, carbohydrates, tricarboxylic acid (TCA) cycle intermediates and phenylpropanoid-related substances, were identified during CA. The gene-metabolite network extensively outlined the biological processes associated with the utilization of sugars, activation of amino acid metabolism, TCA cycle and phenylpropanoid biosynthesis in tobacco under CA. The results of our present study provide a comprehensive view of signal transduction and regulation, gene expression and dynamic changes in metabolites during CA.
PMID: 32251321
Sci Rep , IF:3.998 , 2020 Mar , V10 (1) : P5290 doi: 10.1038/s41598-020-62090-z
Cold stress changes antioxidant defense system, phenylpropanoid contents and expression of genes involved in their biosynthesis in Ocimum basilicum L.
Department of Plant Production and Genetics, Faculty of Agriculture, Urmia University, Urmia, Iran.; Department of Agricultural Biotechnology, Institute of Biotechnology, Urmia University, Urmia, Iran.; Department of Plant Production and Genetics, Faculty of Agriculture, Urmia University, Urmia, Iran. b.abdollahi@urmia.ac.ir.; Department of Agricultural Biotechnology, Institute of Biotechnology, Urmia University, Urmia, Iran. b.abdollahi@urmia.ac.ir.; Department of Horticultural Science, Faculty of Agriculture, Urmia University, Urmia, Iran.
Environmental stresses might alter the activity of antioxidant defense system and both quantity and quality of the essential oil constituents in aromatic plants. In the current study, a greenhouse experiment was designed to assess the influence of cold stress on total phenolic (TPC) and flavonoid contents (TFC), DPPH radical scavenging, antioxidant and phenylalanine ammonia-lyase (PAL) enzymes activity and content of phenylpropanoid compounds in Ocimum basilicum L. The genes expression levels of chavicol O-methyl transferase (CVOMT), cinnamate 4-hydroxylase (C4H), eugenol synthase 1 (EGS1) and eugenol O-methyl transferase (EOMT) were also investigated. Results revealed the highest TPC, TFC and DPPH at 4 degrees C for 12 h. Positive significant correlation was observed between TFC and DPPH, as well as TPC and PAL enzyme activity. The highest activity of superoxide dismutase and guaiacol peroxidase was recorded in 4 degrees C for 48 h, while this treatment caused the highest reduction in the activities of ascorbate peroxidase and catalase. In plants exposed to 10 degrees C for 48 h, the contents of methyleugenol and methylchavicol was positively associated with the expression levels of EGS1 and EOMT. A positive correlation was also found between C4H expression and eugenol, methyleugenol and methylchavicol contents under 4 degrees C for 12 h.
PMID: 32210286
Sci Rep , IF:3.998 , 2020 Mar , V10 (1) : P4602 doi: 10.1038/s41598-020-61317-3
Cloning and characterization of two chlorophyll A/B binding protein genes and analysis of their gene family in Camellia sinensis.
Nanfang College of Sun Yat-sen University, Guangzhou, 510970, China. xianwenli01@sina.com.; College of Life Science, Xinyang Normal University, Xinyang, 464000, China. xianwenli01@sina.com.; Nanfang College of Sun Yat-sen University, Guangzhou, 510970, China.; College of Life Science, Xinyang Normal University, Xinyang, 464000, China.
In this study, two chlorophyll A/B binding protein (CAB) genes (CsCP1 and CsCP2) in tea plant were cloned. The proteins encoded by these genes belong to the external or internal antenna proteins of PS II, respectively. They may be the targets of physiological regulation for tea leaf cell PS II because they all contain multiple functional domains and modifiable sites. The CAB gene family in the tea genome consists of 25 homologous genes. We measured the expression patterns of ten genes in the CsCP1 and CsCP2 subfamily under six different stresses. CsCP1 expression was inhibited in response to 6 kinds of stress; CsCP2 expression was slightly upregulated only after cold stress and ABA treatment. However, the expression levels of CSA016997 and CSA030476 were upregulated significantly in the six stresses. The results suggested that the 10 CAB genes may have different functions in tea leaves. Moreover, changes in the expression of the 10 genes under stress appear to be related to ABA- and MeJA-dependent signalling pathways, and their responses to MeJA treatment is faster than those to ABA. In addition, we introduced our experiences for cloning the genes in the context of complex genomes.
PMID: 32165676
Sci Rep , IF:3.998 , 2020 Mar , V10 (1) : P4489 doi: 10.1038/s41598-020-61081-4
Correlation-based network analysis combined with machine learning techniques highlight the role of the GABA shunt in Brachypodium sylvaticum freezing tolerance.
Department of Plant Sciences, University of California, Davis, California, USA.; School of Plant Sciences and Food Security, Tel Aviv University, Tel Aviv, Israel.; DOE Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, CA, 94598, USA.; Department of Life Sciences, Ben Gurion University of the Negev, Beer Sheva, Israel.; Department of Plant Sciences, University of California, Davis, California, USA. eblumwald@ucdavis.edu.
Perennial grasses will account for approximately 16 billion gallons of renewable fuels by the year 2022, contributing significantly to carbon and nitrogen sequestration. However, perennial grasses productivity can be limited by severe freezing conditions in some geographical areas, although these risks could decrease with the advance of climate warming, the possibility of unpredictable early cold events cannot be discarded. We conducted a study on the model perennial grass Brachypodium sylvaticum to investigate the molecular mechanisms that contribute to cold and freezing adaption. The study was performed on two different B. sylvaticum accessions, Ain1 and Osl1, typical to warm and cold climates, respectively. Both accessions were grown under controlled conditions with subsequent cold acclimation followed by freezing stress. For each treatment a set of morphological parameters, transcription, metabolite, and lipid profiles were measured. State-of-the-art algorithms were employed to analyze cross-component relationships. Phenotypic analysis revealed higher adaption of Osl1 to freezing stress. Our analysis highlighted the differential regulation of the TCA cycle and the GABA shunt between Ain1 and Osl1. Osl1 adapted to freezing stress by repressing the GABA shunt activity, avoiding the detrimental reduction in fatty acid biosynthesis and the concomitant detrimental effects on membrane integrity.
PMID: 32161322
Sci Rep , IF:3.998 , 2020 Mar , V10 (1) : P5733 doi: 10.1038/s41598-020-62458-1
Genome-wide identification and expression analysis of the CBF/DREB1 gene family in lettuce.
U.S. Department of Agriculture, Agricultural Research Service, Salinas, CA, 93905, USA.; Department of Horticulture, University of Arkansas, Fayetteville, AR, 72701, USA.; U.S. Department of Agriculture, Agricultural Research Service, Salinas, CA, 93905, USA. Beiquan.mou@usda.gov.
The C-repeat binding factor (CBF)/dehydration-responsive element binding (DREB1) proteins play a prominent role in freezing tolerance and are highly conserved in higher plants. Here we performed a genome-wide search of the CBF/DREB1 gene family in lettuce (Lactuca sativa L.) and identified 14 members of the family with one member gene containing a non-sense mutation within the AP2 DNA-binding domain. A comprehensive phylogenetic analysis of the CBF/DREB1 family members in 20 plant species from the Asterid or Rosid clade provided evidence that tandem duplication played an important role in the expansion of the CBF/DREB1 family. Expression analysis showed that twelve of the lettuce CBF genes were responsive to low temperature (4 degrees C), and that three and six of them could also be responsive to salt and heat stresses, respectively. Unlike Arabidopsis thaliana whose members of the CBF/DREB1 family respond only to a particular stress, lettuce CBFs provide wider protection from combinations of abiotic stresses. A global transcriptome analysis revealed distinctive temporal expression patterns among the cold-regulated genes in lettuce plants exposed to low temperature. Genes induced throughout the cold treatment are enriched in functions associated with protection from UV and high-light intensity and the genes suppressed after 7 days of cold exposure are enriched in photosynthesis-associated functions. These results provide insight into the molecular evolutionary properties of the CBF/DREB1 gene family in lettuce and a reference for genetic improvement of the lettuce response to cold acclimation.
PMID: 32235838
Plant Physiol Biochem , IF:3.72 , 2020 Mar , V148 : P220-227 doi: 10.1016/j.plaphy.2020.01.017
Hormonal and enzymatic responses of maize seedlings to chilling stress as affected by triazoles seed treatments.
China Agricultural University, Beijing, 100193, China.; China Agricultural University, Beijing, 100193, China; State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, 712100, China. Electronic address: seedling@cau.edu.cn.
Triazole fungicides have been used for seed treatment to control soilborne diseases of maize, but seedlings coming from triazole-coated seed show serious phytotoxicity under chilling stress. To understand this phytotoxic impact, maize seed was treated with four triazoles fungicides and the corresponding seedlings were analysed on growth and gene expression. We found that maize seed coated with difenoconazole and tebuconazole exhibited either no or increased effects on germination and growth of maize at 25 degrees C, regardless of chemical concentrations. When maize seedlings were subjected to chilling treatment, however, their growth was significantly inhibited, and the inhibition was positively correlated with the rate of triazole application. Mesocotyl length decreased by 32.19-44.73% by difenoconazole, and 23.53-32.08% by tebuconazolet at rates of 1:50 and 1:25, respectively. However, myclobutanil did not have any effects at any temperatures. The contents of the gibberellin GA12 and abscisic acid in maize seedlings developed from difenoconazole- or tebuconazole-coated seed were significantly increased under chilling stress. The expression of two key catabolic enzyme genes, GA2ox3 and GA2ox4, was significantly up-regulated immediately following chilling stress and 2 days after recovery at 25 degrees C in the seedlings treated with difenoconazole or tebuconazole. This imbalance in phytohormones may explain why difenoconazole- or tebuconazole-coated seed more likely results in the phytotoxicity of maize seedlings under a low temperature condition during seed emergence and seedling growth. Since myclobutanil did not have this negative effect, it can be applied for seed coating in areas where temperatures are low during early seedling growth.
PMID: 31978750
BMC Genomics , IF:3.594 , 2020 Mar , V21 (1) : P200 doi: 10.1186/s12864-020-6582-4
Evolution of PHAS loci in the young spike of Allohexaploid wheat.
Crop Research Institute, Shandong Academy of Agricultural Sciences, Jinan, 250100, Shandong, China. zhangrongzhi1981@126.com.; Key Laboratory of Wheat Biology and Genetic Improvement on North Yellow and Huai River Valley, Ministry of Agriculture, Jinan, 250100, Shandong, China. zhangrongzhi1981@126.com.; National Engineering Laboratory for Wheat and Maize, Jinan, 250100, Shandong, China. zhangrongzhi1981@126.com.; BGI Institute of Applied Agriculture, BGI-Shenzhen, Shenzhen, 518120, China.; Crop Research Institute, Shandong Academy of Agricultural Sciences, Jinan, 250100, Shandong, China.; Key Laboratory of Wheat Biology and Genetic Improvement on North Yellow and Huai River Valley, Ministry of Agriculture, Jinan, 250100, Shandong, China.; National Engineering Laboratory for Wheat and Maize, Jinan, 250100, Shandong, China.; Crop Research Institute, Shandong Academy of Agricultural Sciences, Jinan, 250100, Shandong, China. zsjhappy@163.com.; Key Laboratory of Wheat Biology and Genetic Improvement on North Yellow and Huai River Valley, Ministry of Agriculture, Jinan, 250100, Shandong, China. zsjhappy@163.com.; National Engineering Laboratory for Wheat and Maize, Jinan, 250100, Shandong, China. zsjhappy@163.com.; Crop Research Institute, Shandong Academy of Agricultural Sciences, Jinan, 250100, Shandong, China. lgy111@126.com.; Key Laboratory of Wheat Biology and Genetic Improvement on North Yellow and Huai River Valley, Ministry of Agriculture, Jinan, 250100, Shandong, China. lgy111@126.com.; National Engineering Laboratory for Wheat and Maize, Jinan, 250100, Shandong, China. lgy111@126.com.
BACKGROUND: PhasiRNAs (phased secondary siRNAs) play important regulatory roles in the development processes and biotic or abiotic stresses in plants. Some of phasiRNAs involve in the reproductive development in grasses, which include two categories, 21-nt (nucleotide) and 24-nt phasiRNAs. They are triggered by miR2118 and miR2275 respectively, in premeiotic and meiotic anthers of rice, maize and other grass species. Wheat (Triticum aestivum) with three closely related subgenomes (subA, subB and subD), is a model of allopolyploid in plants. Knowledge about the role of phasiRNAs in the inflorescence development of wheat is absent until now, and the evolution of PHAS loci in polyploid plants is also unavailable. RESULTS: Using 261 small RNA expression datasets from various tissues, a batch of PHAS (phasiRNA precursors) loci were identified in the young spike of wheat, most of which were regulated by miR2118 and miR2275 in their target site regions. Dissection of PHAS and their trigger miRNAs among the diploid (AA and DD), tetraploid (AABB) and hexaploid (AABBDD) genomes of Triticum indicated that distribution of PHAS loci were dominant randomly in local chromosomes, while miR2118 was dominant only in the subB genome. The diversity of PHAS loci in the three subgenomes of wheat and their progenitor genomes (AA, DD and AABB) suggested that they originated or diverged at least before the occurrence of the tetraploid AABB genome. The positive correlation between the PHAS loci or the trigger miRNAs and the ploidy of genome indicated the expansion of genome was the major drive force for the increase of PHAS loci and their trigger miRNAs in Triticum. In addition, the expression profiles of the PHAS transcripts suggested they responded to abiotic stresses such as cold stress in wheat. CONCLUSIONS: Altogether, non-coding phasiRNAs are conserved transcriptional regulators that display quick plasticity in Triticum genome. They may be involved in reproductive development and abiotic stress in wheat. It could be referred to molecular research on male reproductive development in Triticum.
PMID: 32131726
BMC Genomics , IF:3.594 , 2020 Mar , V21 (1) : P191 doi: 10.1186/s12864-020-6601-5
Genome-wide identification of CNGC genes in Chinese jujube (Ziziphus jujuba Mill.) and ZjCNGC2 mediated signalling cascades in response to cold stress.
College of Horticulture, Hebei Agricultural University, Baoding, 071001, Hebei, China.; Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, 071001, Hebei, China.; College of Life Science, Hebei Agricultural University, Baoding, 071001, Hebei, China.; College of Horticulture, Hebei Agricultural University, Baoding, 071001, Hebei, China. lmj1234567@aliyun.com.; Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, 071001, Hebei, China. lmj1234567@aliyun.com.; Beijing Collaborative Innovation Center for Eco-environmental Improvement with Forestry and Fruit Trees, Beijing, 100000, China. lmj1234567@aliyun.com.
BACKGROUNDS: Cyclic nucleotide gated channels (CNGCs) play multifaceted roles in plant physiological processes, especially with respect to signalling processes, plant development, and responses to environmental stresses. However, little information is known about the CNGC family in the large cosmopolitan family Rhamnaceae, which has strong tolerance to biotic and abiotic stresses. RESULTS: In the current study, a total of 15 ZjCNGCs which located on 7 chromosomes were firstly identified in Chinese jujube (Ziziphus jujuba Mill.), the most important species of Rhamnaceae in terms of economic and ecological values. Phylogenetic analysis showed that these ZjCNGCs could be classified into four groups, ZjCNGC12 belonged to group IVA, and ZjCNGC13, 14, 15 belonged to group IVB. In addition, the paralogous and orthologous homology duplication of ZjCNGC15 occurred during the evolutionary process. The characteristics of ZjCNGCs regarding to exon-intron numbers and post-translational modifications showed diversified structures and functions. Motif composition and protein sequence analysis revealed that the phosphate-binding cassette and hinge regions were conserved among ZjCNGCs. Prediction of the cis-acting regulatory elements and expression profiles by real-time quantitative PCR analysis showed that some of the ZjCNGCs responded to environmental changes, especially ZjCNGC2, which was significantly downregulated in response to cold stress, and ZjCNGC4 was highly induced in response to cold, salt and alkaline stresses. ZjCNGC13 and 14 were highly induced in the phytoplasma-resistant cultivar and downregulated in the susceptible cultivar. Furthermore, ZjCNGC2 could be regulated by cAMP treatment, microtubule changes and interact with ZjMAPKK4, which suggested that cAMP and microtubule might play important roles in ZjCNGC2 mediated ZjMAPKK4 signalling transduction involved in cold stress. CONCLUSIONS: The identification and classification analysis of ZjCNGCs were firstly reported, and some key individual ZjCNGCs might play essential roles in the response to biotic and abiotic stresses, especially ZjCNGC2 mediated ZjMAPKK4 signalling transduction involved in cold stress. This systematic analysis could provide important information for further functional characterization of ZjCNGCs with the aim of breeding stress-resistant cultivars.
PMID: 32122304
Plant Sci , IF:3.591 , 2020 Mar , V292 : P110375 doi: 10.1016/j.plantsci.2019.110375
Overexpression of an AP2/ERF family gene, BpERF13, in birch enhances cold tolerance through upregulating CBF genes and mitigating reactive oxygen species.
State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, PR China.; Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing 100083, PR China.; Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, PR China.; State Key Laboratory for Crop Genetics and Germplasm Enhancement, JiangSu Collaborative Innovation Center for Modern Crop Production, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu, 210095, PR China.; State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, PR China. Electronic address: liuguifeng@126.com.; College of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI, 49931, United States. Electronic address: hairong@mtu.edu.
The AP2/ERF (APETALA2/ethylene-responsive factor) family of transcription factors (TF) is involved in regulating biotic and abiotic stress responses in plants. To explore the role of AP2/ERFs in cold tolerance in woody plants, BpERF13 was cloned and characterized in Betula platyphylla (white birch), a species primarily found in Asia in temperate and boreal climates. Based on phylogenetic analysis, BpERF13 is a member of the IXb subfamily of ERFs. Using qRT-PCR, we found that BpERF13 was differentially expressed in different tissues, and its expression could be induced by cold treatment (4 degrees C). BpERF13 protein, fused with GFP, was exclusively localized to nuclei. To further assess the role of BpERF13 in cold tolerance, BpERF13 overexpression (OE) transgenic lines were generated in B. platyphylla and used for cold stress treatment and biochemical/physiological studies. BpERF13 overexpression lines had significantly increased tolerance to subfreezing treatment and reduced reactive oxygen species. Using a TF-centered yeast one-hybrid (Y1H) experimental system, we showed that BpERF13 could bind to LTRECOREATCOR15 and MYBCORE cis-elements to activate a reporter gene. ChIP-seq and ChIP-PCR experiments further demonstrated that BpERF13 bound to these cis-elements when present in the 5' proximal regions of superoxide dismutase (SOD), peroxidase (POD), and C-repeat-binding factor (CBF) genes. qRT-PCR was employed to examine the expression levels of these genes in response to cold stress; SOD, POD, and CBF genes were significantly upregulated in BpERF13 transgenic lines compared to wild-type plants in response to cold stress. These results indicate that the transcription factor BpERF13 regulates physiological processes underlying cold tolerance in woody plants.
PMID: 32005381
Plant Sci , IF:3.591 , 2020 Mar , V292 : P110388 doi: 10.1016/j.plantsci.2019.110388
Biochemical and molecular responses during overwintering of red clover populations recurrently selected for improved freezing tolerance.
Agriculture and Agri-Food Canada, Quebec City, Canada. Electronic address: BertrandAnnick.Bertrand@canada.ca.; Agriculture and Agri-Food Canada, Quebec City, Canada.; Centre de Recherche Sur Les Grains Inc. (CEROM), Beloeil, Canada.; Agriculture and Agri-Food Canada, Kentville, Canada.
Low freezing tolerance reduces the persistence of red clover under northern climate. The incidence of winter damages in perennial crops could increase in the future due to the adverse effects of the predicted warmer fall temperature on plant cold acclimation. To accelerate breeding progress, two cultivars of red clover Christie (C-TF0) and Endure (E-TF0) were exposed to a recurrent selection protocol for freezing tolerance performed indoor. New populations were obtained after five (C-TF5 and E-TF5), six (C-TF6 and E-TF6), and seven (C-TF7 and E-TF7) cycles of recurrent selection. These populations were overwintered under natural conditions and monitored for freezing tolerance and cold-induced molecular traits. Freezing tolerance was improved by up to 6 degrees C in recurrently selected populations when compared to initial cultivars confirming that further progress are achieved with advanced cycles of selection. Monthly analysis of biochemical changes shows that higher starch concentrations at the onset of the fall hardening period are contributing to the acquisition of superior freezing tolerance through its impact on sucrose accumulation. They also contribute to the vigor of spring regrowth by sustaining more pinitol and proline synthesis. Larger concentrations of these metabolites in populations with higher levels of freezing tolerance (TF7) hint at their involvement in winter survival of red clover. Among genes differentially expressed in response to both cold acclimation and recurrent selection, a concomitant cold induction of APPR9 and cold repression of 1-aminocyclopropane-carboxylate synthase suggests a link between the repression of a pathway regulated by ethylene and the improvement of freezing tolerance in red clover.
PMID: 32005393
BMC Plant Biol , IF:3.497 , 2020 Mar , V20 (1) : P99 doi: 10.1186/s12870-020-2301-1
Identification of tissue-specific and cold-responsive lncRNAs in Medicago truncatula by high-throughput RNA sequencing.
State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093, People's Republic of China.; Research Network of Global Change Biology, Beijing Institutes of Life Science, the Chinese Academy of Sciences, Beijing, 100101, People's Republic of China.; University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China.; State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093, People's Republic of China. whzhang@ibcas.ac.cn.; Research Network of Global Change Biology, Beijing Institutes of Life Science, the Chinese Academy of Sciences, Beijing, 100101, People's Republic of China. whzhang@ibcas.ac.cn.; University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China. whzhang@ibcas.ac.cn.; Inner Mongolia Research Center for Prataculture, the Chinese Academy of Sciences, Beijing, 100093, People's Republic of China. whzhang@ibcas.ac.cn.
BACKGROUND: Long non-coding RNAs (lncRNAs) play important roles in the regulation of plant responses to environmental stress by acting as essential regulators of gene expression. However, whether and how lncRNAs are involved in cold acclimation-dependent freezing tolerance in plants remains largely unknown. Medicago truncatula is a prominent model for studies of legume genomics, and distinguished by its cold-acclimation characteristics. To determine the roles of lncRNAs in plant cold stress response, we conducted genome-wide high-throughput sequencing in the legume model plant M. truncatula. RESULTS: RNA-seq data were generated from twelve samples for the four treatments, i.e., non-cold treated leaves and roots, cold-treated leaves and roots of M. truncatula Jemalong A17 seedlings. A total of 1204 million raw reads were generated. Of them, 1150 million filtered reads after quality control (QC) were subjected to downstream analysis. A large number of 24,368 unique lncRNAs were identified from the twelve samples. Among these lncRNAs, 983 and 1288 were responsive to cold treatment in the leaves and roots, respectively. We further found that the intronic-lncRNAs were most sensitive to the cold treatment. The cold-responsive lncRNAs were unevenly distributed across the eight chromosomes in M. truncatula seedlings with obvious preferences for locations. Further analyses revealed that the cold-responsive lncRNAs differed between leaves and roots. The putative target genes of the lncRNAs were predicted to mainly involve the processes of protein translation, transport, metabolism and nucleic acid transcription. Furthermore, the networks of a tandem array of CBF/DREB1 genes that were reported to be located in a major freezing tolerance QTL region on chromosome 6 and their related lncRNAs were dissected based on their gene expression and chromosome location. CONCLUSIONS: We identified a comprehensive set of lncRNAs that were responsive to cold treatment in M. truncatula seedlings, and discovered tissue-specific cold-responsive lncRNAs in leaves and roots. We further dissected potential regulatory networks of CBF Intergenic RNA (MtCIR1) and MtCBFs that play critical roles in response and adaptation of M. truncatula to cold stress.
PMID: 32138663
Plant Mol Biol , IF:3.302 , 2020 Mar , V102 (4-5) : P447-462 doi: 10.1007/s11103-019-00957-0
A novel basic helix-loop-helix transcription factor, ZjICE2 from Zoysia japonica confers abiotic stress tolerance to transgenic plants via activating the DREB/CBF regulon and enhancing ROS scavenging.
Department of Biotechnology, Jeju National University, Jeju, Korea.; Subtropical Horticulture Research Institute, Jeju National University, Jeju, Korea.; Subtropical Horticulture Research Institute, Jeju National University, Jeju, Korea. honggyu@jejunu.ac.kr.; Department of Life Science, Shangqiu Normal University, Henan, China.; Faculty of Science Education, Jeju National University, Jeju, Korea.; Department of Biotechnology, Jeju National University, Jeju, Korea. hyoyeon@jejunu.ac.kr.; Subtropical Horticulture Research Institute, Jeju National University, Jeju, Korea. hyoyeon@jejunu.ac.kr.
KEY MESSAGE: ZjICE2 works as a positive regulator in abiotic stress responses and ZjICE2 is a valuable genetic resource to improve abiotic stress tolerance in the molecular breeding program of Zoysia japonica. The basic helix-loop-helix (bHLH) family transcription factors (TFs) play an important role in response to biotic or abiotic stresses in plants. However, the functions of bHLH TFs in Zoysia japonica, one of the warm-season turfgrasses, remain poorly understood. Here, we identified ZjICE2 from Z. japonica, a novel MYC-type bHLH transcription factor that was closely related to ICE homologs in the phylogenetic tree, and its expression was regulated by various abiotic stresses. Transient expression of ZjICE2-GFP in onion epidermal cells revealed that ZjICE2 was a nuclear-localized protein. Also, ZjICE2 bound the MYC cis-element in the promoter of dehydration responsive element binding 1 of Z. japonica (ZjDREB1) using yeast one-hybrid assay. A phenotypic analysis showed that overexpression of the ZjICE2 in Arabidopsis enhanced tolerance to cold, drought, and salt stresses. The transgenic Arabidopsis and Z. japonica accumulated more transcripts of cold-responsive DREB/CBFs and their downstream genes than the wild type (WT) after cold treatment. Furthermore, the transgenic plants exhibited an enhanced Reactive oxygen species (ROS) scavenging ability, which resulted in an efficient maintenance of oxidant-antioxidant homeostasis. In addition, overexpression of the ZjICE2 in Z. japonica displayed intensive cold tolerance with increases in chlorophyll contents and photosynthetic efficiency. Our study suggests that ZjICE2 works as a positive regulator in abiotic stress responses and the ICE-DREB/CBFs response pathway involved in cold stress tolerance is also conserved in Z. japonica. These results provide a valuable genetic resource for the molecular breeding program especially for warm-season grasses as well as other leaf crop plants.
PMID: 31898148
Funct Plant Biol , IF:2.617 , 2020 Mar , V47 (4) : P327-341 doi: 10.1071/FP19199
Molecular characterisation and expression analysis of NAC transcription factor genes in wild Medicago falcata under abiotic stresses.
Key Laboratory of Forage and Endemic Crop Biotechnology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot 010070, P.R. China; and State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot 010070, P.R.China; and Corresponding authors. Emails: zhangliquan430@126.com; ydniu@imu.edu.cn.; Key Laboratory of Forage and Endemic Crop Biotechnology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot 010070, P.R. China.
The No apical meristem-Arabidopsis transcription activation factor-Cup-shaped cotyledon (NAC) proteins play vital roles in plant development processes and responses to abiotic stress. In this study, 146 unigenes were identified as NAC genes from wild Medicago falcata L. by RNA sequencing. Among these were 30 full-length NACs, which, except for MfNAC63, MfNAC64 and MfNAC91, contained a complete DNA-binding domain and a variable transcriptional activation region. Sequence analyses of MfNACs along with their Arabidopsis thaliana (L.) Heynh. counterparts allowed these proteins to be phylogenetically classified into nine groups. MfNAC35, MfNAC88, MfNAC79, MfNAC26 and MfNAC95 were found to be stress-responsive genes. The eight MfNAC genes that were chosen for further analysis had different expression abilities in the leaves, stems and roots of M. falcata. Additionally, their expression levels were regulated by salinity, drought and cold stress, and ABA. This study will be useful for understanding the roles of MfNACs in wild M. falcata and could provide important information for the selection of candidate genes associated with stress tolerance.
PMID: 32092285
J Sci Food Agric , IF:2.614 , 2020 Mar , V100 (5) : P2136-2144 doi: 10.1002/jsfa.10237
Regulation of the biosynthesis of endogenous nitric oxide and abscisic acid in stored peaches by exogenous nitric oxide and abscisic acid.
Department of Horticulture, College of Agriculture, Shihezi University, Shihezi, China.; College of Chemistry and Material Science, Shandong Agricultural University, Taian, China.
BACKGROUND: Nitric oxide (NO) and abscisic acid (ABA) are important regulators of plant response to cold stress, and they interact in response to cold signals. The primary goal of this study was to determine the roles of exogenous NO and ABA on the synthesis of endogenous NO and ABA in cold-stored peach fruit. RESULTS: Exogenous NO and ABA maintained a relatively high content of NO, increased nitrate reductase (NR) activity, and inhibited the activity of NO synthase (NOS)-like and the levels of polyamine biosynthesis in peaches during cold storage. Treatments of potassium 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (c-PTIO), NO, N-nitro-l-Arg-methyl ester (L -NAME), and sodium tungstate did not influence ABA content. Exogenous ABA increased the content of carotenoids and the activities of aldehyde oxidase (AO), 9-cis-epoxycarotenoid dioxygenase (NCED), and zeaxanthin epoxidase (ZEP) of ABA synthesis in peaches during cold storage, and upregulated the gene expression of PpAO1, PpNCED1, PpNCED2, and PpZEP. The production of endogenous NO was differentially inhibited by NO scavengers, ABA inhibitors, and NR inhibitors, but not affected by NOS-like inhibitors during cold storage. CONCLUSION: Exogenous NO and ABA can induce endogenous NO synthesis in cold-stored peaches by the nitrate reductase pathway, and ABA can mediate endogenous ABA synthesis by the autocatalytic reaction. NO does not regulate ABA synthesis. (c) 2019 Society of Chemical Industry.
PMID: 31884697