New Phytol , IF:10.151 , 2021 Sep doi: 10.1111/nph.17745
Redox-mediated structural and functional switching of CBFs enhances plant cold tolerance.
Division of Applied Life Science (BK21+) and PMBBRC, Gyeongsang National University, Jinju, 52828, Korea.; Department of Biomedical Science & Engineering, Konkuk University, Seoul, 05029, Korea.
C-repeat binding factors (CBFs) are key cold-responsive transcription factors that play pleiotropic roles in the cold acclimation, growth, and development of plants. Cold-sensitive cbf knockout mutants and cold-tolerant CBF overexpression lines exhibit abnormal phenotypes at warm temperature, suggesting that CBF activity is precisely regulated, and a critical threshold level must be maintained for proper plant growth at normal conditions. Cold-inducible CBFs also exist in warm-climate plants but as inactive disulfide-bonded oligomers. However, upon translocation to the nucleus under a cold snap, the h2-isotype of cytosolic thioredoxin (Trx-h2), reduces the oxidized (inactive) CBF oligomers and the newly synthesized CBF monomers, thus producing reduced (active) CBF monomers. Thus, the redox-dependent structural switching and functional activation of CBFs protect plants under cold stress.
PMID: 34537981
Plant Biotechnol J , IF:9.803 , 2021 Sep doi: 10.1111/pbi.13705
ERF9 of Poncirus trifoliata (L.) Raf. undergoes feedback regulation by ethylene and modulates cold tolerance via regulating a glutathione S-transferase U17 gene.
Key Laboratory of Horticultural Plant Biology, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, China.
Plant ethylene-responsive factors (ERFs) play essential roles in cold stress response, but the molecular mechanisms underlying this process remain poorly understood. In this study, we characterized PtrERF9 from trifoliate orange (Poncirus trifoliata (L.) Raf.), a cold-hardy plant. PtrERF9 was up-regulated by cold in an ethylene-dependent manner. Overexpression of PtrERF9 conferred prominently enhanced freezing tolerance, which was drastically impaired when PtrERF9 was knocked down by virus-induced gene silencing. Global transcriptome profiling indicated that silencing of PtrERF9 resulted in substantial transcriptional reprogramming of stress-responsive genes involved in different biological processes. PtrERF9 was further verified to directly and specifically bind with the promoters of glutathione S-transferase U17 (PtrGSTU17) and ACC synthase1 (PtrACS1). Consistently, PtrERF9-overexpressing plants had higher levels of PtrGSTU17 transcript and GST activity, but accumulated less ROS, whereas the silenced plants showed the opposite changes. Meanwhile, knockdown of PtrERF9 decreased PtrACS1 expression, ACS activity and ACC content. However, overexpression of PtrERF9 in lemon, a cold-sensitive species, caused negligible alterations of ethylene biosynthesis, which was attributed to perturbed interaction between PtrERF9, along with lemon homologue ClERF9, and the promoter of lemon ACS1 gene (ClACS1) due to mutation of the cis-acting element. Taken together, these results indicate that PtrERF9 acts downstream of ethylene signalling and functions positively in cold tolerance via modulation of ROS homeostasis by regulating PtrGSTU17. In addition, PtrERF9 regulates ethylene biosynthesis by activating PtrACS1 gene, forming a feedback regulation loop to reinforce the transcriptional regulation of its target genes, which may contribute to the elite cold tolerance of Poncirus trifoliata.
PMID: 34510677
Ecol Lett , IF:9.492 , 2021 Oct , V24 (10) : P2267-2281 doi: 10.1111/ele.13827
Global trends in phenotypic plasticity of plants.
Sustainability Research Centre, Life Sciences Faculty, Universidad Andres Bello, Santiago, Chile.; Departamento de Biologia, Universidad de La Serena, La Serena, Chile.; Laboratorio de Biologia Vegetal, Instituto de Ciencias Biologicas, Universidad de Talca, Talca, Chile.; Departamento de Biogeografia y Cambio Global, LINCGlobal, Museo Nacional de Ciencias Naturales, MNCN-CSIC, Madrid, Espana.; Area de Biodiversidad y Conservacion, Universidad Rey Juan Carlos, Mostoles, Madrid, Espana.; Departamento de Botanica, Universidad de Concepcion, Concepcion, Chile.
Predicting plastic responses is crucial to assess plant species potential to adapt to climate change, but little is known about which factors drive the biogeographical patterns of phenotypic plasticity in plants. Theory predicts that climatic variability would select for increased phenotypic plasticity, whereas evidence indicates that stressful conditions can limit phenotypic plasticity. Using a meta-analytic, phylogeny-corrected approach to global data on plant phenotypic plasticity, we tested whether latitude, climate, climatic variability and/or stressful conditions are predictors of plastic responses at a biogeographical scale. We found support for a positive association between phenotypic plasticity and climatic variability only for plasticity in allocation. Plasticity in leaf morphology, size and physiology were positively associated with mean annual temperature. We also found evidence that phenotypic plasticity in physiology is limited by cold stress. Overall, plant plastic responses to non-climatic factors were stronger than responses to climatic factors. However, while climatic conditions were associated with plant plastic responses to climatic factors, they generally did not relate to plastic responses to other abiotic or biotic factors. Our study highlights the need to consider those factors that favour and limit phenotypic plasticity in order to improve predictive frameworks addressing plant species' potential to adapt to climate change.
PMID: 34216183
Food Chem , IF:7.514 , 2021 Oct , V358 : P129867 doi: 10.1016/j.foodchem.2021.129867
Salicylic acid treatment mitigates chilling injury in peach fruit by regulation of sucrose metabolism and soluble sugar content.
Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China.; The New Zealand Institute for Plant and Food Research Limited, Food Industry Science Centre, Private Bag 11600, Palmerston North 4442, New Zealand.; Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China. Electronic address: bijinfeng@163.com.; Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China. Electronic address: duanyuquan@caas.cn.
Peach fruit stored in the cold are susceptible to chilling injury. A pre-storage treatment with the natural hormone salicylic acid can alleviate chilling damage, although the mechanism is unclear. We found that a treatment with 1 mumol L(-1) salicylic acid for 15 min prior to storage at 4 degrees C delayed and reduced fruit internal browning, a symptom of chilling injury. Salicylic acid had a large effect on sugar metabolism, increasing total soluble sugars via a substantial increase in sucrose content. The transcript abundance of genes related to sucrose biosynthesis and degradation was significantly regulated by salicylic acid, consistent with the changes in sucrose content. Salicylic acid treatment also increased the expression of two DREB cold stress-related proteins, transcriptional activators that regulate cold resistance pathways. The results show that salicylic acid alleviates chilling injury in peach by multiple mechanisms, including an increased content of sucrose and activation of cold response genes.
PMID: 33979685
J Exp Bot , IF:6.992 , 2021 Sep , V72 (17) : P5942-5960 doi: 10.1093/jxb/erab327
Improving C4 photosynthesis to increase productivity under optimal and suboptimal conditions.
Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK.; Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA.; Centre for Crops Systems Analysis (WUR), Wageningen University, Wageningen, The Netherlands.
Although improving photosynthetic efficiency is widely recognized as an underutilized strategy to increase crop yields, research in this area is strongly biased towards species with C3 photosynthesis relative to C4 species. Here, we outline potential strategies for improving C4 photosynthesis to increase yields in crops by reviewing the major bottlenecks limiting the C4 NADP-malic enzyme pathway under optimal and suboptimal conditions. Recent experimental results demonstrate that steady-state C4 photosynthesis under non-stressed conditions can be enhanced by increasing Rubisco content or electron transport capacity, both of which may also stimulate CO2 assimilation at supraoptimal temperatures. Several additional putative bottlenecks for photosynthetic performance under drought, heat, or chilling stress or during photosynthetic induction await further experimental verification. Based on source-sink interactions in maize, sugarcane, and sorghum, alleviating these photosynthetic bottlenecks during establishment and growth of the harvestable parts are likely to improve yield. The expected benefits are also shown to be augmented by the increasing trend in planting density, which increases the impact of photosynthetic source limitation on crop yields.
PMID: 34268575
Int J Biol Macromol , IF:6.953 , 2021 Oct , V188 : P924-931 doi: 10.1016/j.ijbiomac.2021.07.186
Characterization and functional analysis of Cshsp19.0 encoding a small heat shock protein in Chilo suppressalis (Walker).
College of Horticulture and Plant Protection & Institute of Applied Entomology, Yangzhou University, Yangzhou 225009, China.; Plant Protection and Quarantine Station of Jiangsu Province, Nanjing 210000, China.; College of Horticulture and Plant Protection & Institute of Applied Entomology, Yangzhou University, Yangzhou 225009, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education, Yangzhou University, Yangzhou, China. Electronic address: yzdu@yzu.edu.cn.
Small heat shock proteins (sHSPs) function as ATP-independent chaperones that preserve cellular proteostasis under stressful conditions. In this study, Cshsp19.0, which encodes a new small heat shock protein, was isolated and characterized from Chilo suppressalis (Walker) to better understand the contribution of sHSPs to insect development and stress tolerance. The full-length Cshsp19.0 cDNA was 697 bp and encoded a 19.0 kDa protein with an isoelectric point of 5.95. Phylogenetic analysis and amino acid alignments indicated that Cshsp19.0 is a member of the sHSP family. Cshsp19.0 was expressed at maximal levels in foreguts and showed the least amount of expression in fat bodies. Expression analysis in different developmental stages of C. suppressalis revealed that Cshsp19.0 was most highly expressed in 1st instar larvae. Furthermore, Cshsp19.0 was upregulated when insects were exposed to heat and cold stress for a 2-h period. There were significant differences in the male and female pupae in response to humidity; Cshsp19.0 expression increased in male pupae as RH increased, whereas the inverse pattern was observed in female pupae. Larvae exhibited a lower rate of survival when Cshsp19.0 was silenced by a nanomaterial-promoted RNAi method. The results confirm that Cshsp19.0 functions to increase environmental stress tolerance and regulates physiological activities in C. suppressalis.
PMID: 34352319
Antioxidants (Basel) , IF:6.312 , 2021 Sep , V10 (9) doi: 10.3390/antiox10091457
Positive Interaction between H2O2 and Ca(2+) Mediates Melatonin-Induced CBF Pathway and Cold Tolerance in Watermelon (Citrullus lanatus L.).
State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A&F University, Xianyang 712100, China.; State Key Laboratory of Vegetable Germplasm Innovation, Tianjin 300384, China.
Cold stress is a major environmental factor that detrimentally affects plant growth and development. Melatonin has been shown to confer plant tolerance to cold stress through activating the C-REPEAT BINDING FACTOR (CBF) pathway; however, the underlying modes that enable this function remain obscure. In this study, we investigated the role of H2O2 and Ca(2+) signaling in the melatonin-induced CBF pathway and cold tolerance in watermelon (Citrullus lanatus L.) through pharmacological, physiological, and genetic approaches. According to the results, melatonin induced H2O2 accumulation, which was associated with the upregulation of respiratory burst oxidase homolog D (ClRBOHD) during the early response to cold stress in watermelon. Besides, melatonin and H2O2 induced the accumulation of cytoplasmic free Ca(2+) ([Ca(2+)]cyt) in response to cold. This was associated with the upregulation of cyclic nucleotide-gated ion channel 2 (ClCNGC2) in watermelon. However, blocking of Ca(2+) influx channels abolished melatonin- or H2O2-induced CBF pathway and cold tolerance. Ca(2+) also induced ClRBOHD expression and H2O2 accumulation in early response to cold stress in watermelon. Inhibition of H2O2 production in watermelon by RBOH inhibitor or in Arabidopsis by AtRBOHD knockout compromised melatonin-induced [Ca(2+)]cyt accumulation and melatonin- or Ca(2+)-induced CBF pathway and cold tolerance. Overall, these findings indicate that melatonin induces RBOHD-dependent H2O2 generation in early response to cold stress. Increased H2O2 promotes [Ca(2+)]cyt accumulation, which in turn induces H2O2 accumulation via RBOHD, forming a reciprocal positive-regulatory loop that mediates melatonin-induced CBF pathway and subsequent cold tolerance.
PMID: 34573090
Int J Mol Sci , IF:5.923 , 2021 Sep , V22 (17) doi: 10.3390/ijms22179599
Functional Characterization of the Stipa purpurea P5CS Gene under Drought Stress Conditions.
Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.; Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.; Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, China.; University of Chinese Academy of Sciences, Beijing 100049, China.; Yunnan Population and Family Planning Science and Technology Research Institute, Kunming 650021, China.
Free proline has multiple functions in plant cells, such as regulating osmotic potential and protecting both proteins and cell membranes. The expression of Delta1-Pyrroline-5-carboxylate synthase (P5CS), a key enzyme in the proline biosynthetic pathway, increases under drought, salt and cold stress conditions, causing plant cells to accumulate large amounts of proline. In this study, we cloned and identified the P5CS gene from Stipa purpurea, which has a full-length of 2196 bp and encodes 731 amino acids. A subcellular localization analysis indicated that SpP5CS localized to the cytoplasm. The ectopic overexpression of SpP5CS in Arabidopsis thaliana resulted in higher proline contents, longer roots, higher survival rates and less membrane damage under drought stress conditions compared with wild-type controls. SpP5CS-overexpressing A. thaliana was more resistant to drought stress than the wild type, whereas the deletion mutant sp5cs was less resistant to drought stress. Thus, SpP5CS may be a potential candidate target gene for increasing plant resistance to drought stress.
PMID: 34502515
Front Plant Sci , IF:5.753 , 2021 , V12 : P715767 doi: 10.3389/fpls.2021.715767
Cold-Triggered Induction of ROS- and Raffinose Metabolism in Freezing-Sensitive Taproot Tissue of Sugar Beet.
Department of Plant Physiology, University of Kaiserslautern, Kaiserslautern, Germany.; Department of Biochemistry, FAU Erlangen-Nurnberg, Erlangen, Germany.; CRDS, Sudzucker AG, Obrigheim/Pfalz, Germany.; KWS SAAT SE & Co. KGaA, Einbeck, Germany.
Sugar beet (Beta vulgaris subsp. vulgaris) is the exclusive source of sugar in the form of sucrose in temperate climate zones. Sugar beet is grown there as an annual crop from spring to autumn because of the damaging effect of freezing temperatures to taproot tissue. A collection of hybrid and non-hybrid sugar beet cultivars was tested for winter survival rates and freezing tolerance. Three genotypes with either low or high winter survival rates were selected for detailed study of their response to frost. These genotypes differed in the severity of frost injury in a defined inner region in the upper part of the taproot, the so-called pith. We aimed to elucidate genotype- and tissue-dependent molecular processes during freezing and combined analyses of sugar beet anatomy and physiology with transcriptomic and metabolite profiles of leaf and taproot tissues at low temperatures. Freezing temperatures induced strong downregulation of photosynthesis in leaves, generation of reactive oxygen species (ROS), and ROS-related gene expression in taproots. Simultaneously, expression of genes involved in raffinose metabolism, as well as concentrations of raffinose and its intermediates, increased markedly in both leaf and taproot tissue at low temperatures. The accumulation of raffinose in the pith tissue correlated with freezing tolerance of the three genotypes. We discuss a protective role for raffinose and its precursors against freezing damage of sugar beet taproot tissue.
PMID: 34539707
Plant Cell Physiol , IF:4.927 , 2021 Sep doi: 10.1093/pcp/pcab135
Citrus sinensis CBF1 Functions in Cold Tolerance by Modulating Putrescine Biosynthesis Through Regulation of ARGININE DECARBOXYLASE.
Key Laboratory of Horticultural Plant Biology (MOE), College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China.
C-repeat (CRT) binding factors (CBFs) are well known to act as crucial transcription factors that function in cold stress response. Arginine decarboxylase (ADC)-mediated putrescine biosynthesis has been reported to be activated in plants exposed to cold conditions, but it remains elusive whether CBFs can regulate ADC expression and putrescine accumulation. In this study, we show that cold up-regulated ADC gene (CsADC) and elevation of endogenous putrescine content in sweet orange (Citrus sinensis). Promoter of CsADC contains two CRT sequences that are canonical elements recognized by CBFs. Sweet orange genome contains four CBFs (CsCBF1-4), in which CsCBF1 was significantly induced by cold. CsCBF1, located in the nucleus, was demonstrated to bind directly and specifically to the promoter of CsADC and acted as a transcriptional activator. Overexpression of CsCBF1 led to notable elevation of CsADC and putrescine level in sweet orange transgenic plants, along with remarkably enhanced cold tolerance, relative to the wild type (WT). However, pretreatment with D-arginine, an ADC inhibitor, caused prominent reduction of endogenous putrescine level in the overexpressing lines, accompanied by greatly compromised cold tolerance. Taken together, these results demonstrate that CBF1 of sweet orange directly regulates ADC expression and modulates putrescine synthesis for orchestrating the cold tolerance. Our findings shed light into the transcriptional regulation of putrescine accumulation through targeting the ADC gene in the presence of cold stress. Meanwhile, this study illustrates a new mechanism underlying the CBF-mediated cold stress response.
PMID: 34478552
Ann Bot , IF:4.357 , 2021 Sep , V128 (5) : P559-575 doi: 10.1093/aob/mcab091
Revision of the relationship between anther morphology and pollen sterility by cold stress at the booting stage in rice.
Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan.; National Agriculture and Food Research Organization, Hokkaido Agricultural Research Center, Sapporo, Japan.
BACKGROUND AND AIMS: Cold stress in rice (Oryza sativa) plants at the reproductive stage prevents normal anther development and causes pollen sterility. Tapetum hypertrophy in anthers has been associated with pollen sterility in response to cold at the booting stage. Here, we re-examined whether the relationships between anther abnormality and pollen sterility caused by cold stress at the booting stage in rice can be explained by a monovalent factor such as tapetum hypertrophy. METHODS: After exposing plants to a 4-d cold treatment at the booting stage, we collected and processed anthers for transverse sectioning immediately and at the flowering stage. We anatomically evaluated the effect of cold treatment on anther internal morphologies, pollen fertilities and pollen numbers in the 13 cultivars with various cold sensitivities. KEY RESULTS: We observed four types of morphological anther abnormalities at each stage. Pollen sterility was positively correlated with the frequency of undeveloped locules, but not with tapetum hypertrophy as commonly believed. In cold-sensitive cultivars grown at low temperatures, pollen sterility was more frequent than anther morphological abnormalities, and some lines showed remarkably high pollen sterility without any anther morphological alterations. Most morphological anomalies occurred only in specific areas within large and small locules. Anther length tended to shorten in response to cold treatment and was positively correlated with pollen number. One cultivar showed a considerably reduced pollen number, but fertile pollen grains under cold stress. We propose three possible relationships to explain anther structure and pollen sterility and reduction due to cold stress. CONCLUSIONS: The pollen sterility caused by cold stress at the booting stage was correlated with the frequency of entire locule-related abnormalities, which might represent a phenotypic consequence, but not a direct cause of pollen abortion. Multivalent factors might underlie the complicated relationships between anther abnormality and pollen sterility in rice.
PMID: 34232290
Plant Physiol Biochem , IF:4.27 , 2021 Sep , V167 : P795-805 doi: 10.1016/j.plaphy.2021.09.006
Temporal transcriptome profiling reveals candidate genes involved in cold acclimation of Camellia japonica (Naidong).
College of Landscape and Forestry, Qingdao Agricultural University, Qingdao, 266109, China.; College of Landscape and Forestry, Qingdao Agricultural University, Qingdao, 266109, China; College of Biology and the Environment, Nanjing Forestry University, Nanjing, 210037, China.; College of Landscape and Forestry, Qingdao Agricultural University, Qingdao, 266109, China. Electronic address: sunyk678@qau.edu.cn.
Cold is a common problem that limits the distribution of Camellia. Camellia japonica (Naidong) is the northernmost species of camellia in China, which is a Tertiary remnant species that can adapt to large changes in temperature. An analysis of the transcriptional response of C. japonica (Naidong) to cold is very important for the planting and distribution of camellia. In this study, the rate of H(2)O(2) levels, electrolyte leakage, chlorophyll and sugar content had a higher degree of cold response during 12-72 h period, than other periods (0-12h, 72h-120h) in C. japonica (Naidong) response to cold treatment. We constructed the first full-length C. japonica (Naidong) transcriptome and identified 4544 significantly differentially expressed genes (DEGs). A weighted gene coexpression network analysis showed that carbon metabolism, lipid metabolism, and transcription factors played important roles in the resistance of C. japonica (Naidong) to cold stress, and three hub transcription factor regulatory networks were constructed. In addition, overexpressing CjRAV1 led to cold sensitivity in Arabidopsis thaliana, thus CjRAV1 likely plays a negative regulatory role during cold stress in Camellia japonica. This study deepens our understanding of the regulatory mechanism of C. japonica (Naidong) under cold stress and will benefit genetic improvement of camellia.
PMID: 34530324
Plant Physiol Biochem , IF:4.27 , 2021 Sep , V167 : P862-873 doi: 10.1016/j.plaphy.2021.09.005
Recovery from chilling modulates the acyl-editing of phosphatidic acid molecular species in barley roots (Hordeum vulgare L.).
Universidad Nacional de Rio Cuarto, FCEFQyN, Departamento de Biologia Molecular, Rio Cuarto, Cordoba, Argentina; CONICET, Universidad Nacional de Rio Cuarto, Instituto de Biotecnologia Ambiental y Salud, (INBIAS), Rio Cuarto, Cordoba, Argentina.; Universidad Nacional de Cordoba, Facultad de Ciencias Quimicas, Departamento de Quimica Biologica Ranwel Caputto, Cordoba, Argentina; CONICET, Universidad Nacional de Cordoba, Centro de Investigaciones en Quimica Biologica de Cordoba (CIQUIBIC), Cordoba, Argentina.; Universidad Nacional de Rio Cuarto, FCEFQyN, Departamento de Biologia Molecular, Rio Cuarto, Cordoba, Argentina; CONICET, Universidad Nacional de Rio Cuarto, Instituto de Biotecnologia Ambiental y Salud, (INBIAS), Rio Cuarto, Cordoba, Argentina. Electronic address: lvillasuso@exa.unrc.edu.ar.
In plants, lipid metabolism and remodelling are key mechanisms for survival under temperature stress. The present study attempted to compare the lipid profile in barley roots both under chilling stress treatment and in the subsequent recovery to stress. Lipids were obtained through a single-extraction method with a polar solvent mixture, followed by mass spectrometry analysis. The results indicate that lipid metabolism was significantly affected by chilling. Most of the glycerolipids analysed returned to control values during short- and long-term recovery, whereas several representative phosphatidic acid (PA) molecular species were edited during long-term recovery. Most of the PA molecular species that increased in the long-term had the same acyl chains as the phosphatidylcholine (PC) species that decreased. C34:2 and C36:4 underwent the most remarkable changes. Given that the mechanisms underlying the acyl-editing of PC in barley roots remain elusive, we also evaluated the contribution of lysophosphatidylcholine acyltransferases (HvLPCAT) and phospholipase A (HvPLA). In line with the aforementioned results, the expression of the HvLPCAT and HvPLA genes was up-regulated during recovery from chilling. The differential acyl-editing of PA during recovery, which involves the remodelling of PC, might therefore be a regulatory mechanism of cold tolerance in barley.
PMID: 34536899
BMC Plant Biol , IF:4.215 , 2021 Sep , V21 (1) : P403 doi: 10.1186/s12870-021-03182-4
Mapping freezing tolerance QTL in alfalfa: based on indoor phenotyping.
Institute of Plant Breeding, Genetics and Genomics, The University of Georgia, Athens, GA, USA.; Department of Horticulture, The University of Georgia, Athens, GA, USA.; Institute of Plant Breeding, Genetics and Genomics, The University of Georgia, Athens, GA, USA. cssamm@uga.edu.; Department of Crop and Soil Sciences, The University of Georgia, Athens, GA, USA. cssamm@uga.edu.
BACKGROUND: Winter freezing temperature impacts alfalfa (Medicago sativa L.) persistence and seasonal yield and can lead to the death of the plant. Understanding the genetic mechanisms of alfalfa freezing tolerance (FT) using high-throughput phenotyping and genotyping is crucial to select suitable germplasm and develop winter-hardy cultivars. Several clones of an alfalfa F1 mapping population (3010 x CW 1010) were tested for FT using a cold chamber. The population was genotyped with SNP markers identified using genotyping-by-sequencing (GBS) and the quantitative trait loci (QTL) associated with FT were mapped on the parent-specific linkage maps. The ultimate goal is to develop non-dormant and winter-hardy alfalfa cultivars that can produce extended growth in the areas where winters are often mild. RESULTS: Alfalfa FT screening method optimized in this experiment comprises three major steps: clone preparation, acclimation, and freezing test. Twenty clones of each genotype were tested, where 10 samples were treated with freezing temperature, and 10 were used as controls. A moderate positive correlation (r ~ 0.36, P < 0.01) was observed between indoor FT and field-based winter hardiness (WH), suggesting that the indoor FT test is a useful indirect selection method for winter hardiness of alfalfa germplasm. We detected a total of 20 QTL associated with four traits; nine for visual rating-based FT, five for percentage survival (PS), four for treated to control regrowth ratio (RR), and two for treated to control biomass ratio (BR). Some QTL positions overlapped with WH QTL reported previously, suggesting a genetic relationship between FT and WH. Some favorable QTL from the winter-hardy parent (3010) were from the potential genic region for a cold tolerance gene CBF. The BLAST alignment of a CBF sequence of M. truncatula, a close relative of alfalfa, against the alfalfa reference showed that the gene's ortholog resides around 75 Mb on chromosome 6. CONCLUSIONS: The indoor freezing tolerance selection method reported is useful for alfalfa breeders to accelerate breeding cycles through indirect selection. The QTL and associated markers add to the genomic resources for the research community and can be used in marker-assisted selection (MAS) for alfalfa cold tolerance improvement.
PMID: 34488630
Planta , IF:4.116 , 2021 Sep , V254 (4) : P84 doi: 10.1007/s00425-021-03725-x
Exploring the GRAS gene family in common bean (Phaseolus vulgaris L.): characterization, evolutionary relationships, and expression analyses in response to abiotic stresses.
Plant Genomics and Bioinformatics Laboratory, P.G. Department of Botany, Ramakrishna Mission Vivekananda Centenary College (Autonomous), Rahara, Kolkata, 700118, India.; Department of Botany, Dr. A.P.J. Abdul Kalam Government College, New Town, Rajarhat, India.; Aquatic Bioresource Research Laboratory, Department of Zoology , University of Calcutta, Kolkata, India.; Plant Genomics and Bioinformatics Laboratory, P.G. Department of Botany, Ramakrishna Mission Vivekananda Centenary College (Autonomous), Rahara, Kolkata, 700118, India. discoveranirban@yahoo.co.in.
MAIN CONCLUSION: Genome-wide identification reveals 55 PvuGRAS genes belonging to 16 subfamilies and their gene structures and evolutionary relationships were characterized. Expression analyses highlight their prominence in plant growth, development and abiotic stress responses. GRAS proteins comprise a plant-specific transcription factor family involved in multiple growth regulatory pathways and environmental cues including abiotic/biotic stresses. Despite its crucial importance, characterization of this gene family is still elusive in common bean. A systematic genome-wide scan identified 55 PvuGRAS genes unevenly anchored to the 11 common bean chromosomes. Segmental duplication appeared to be the key driving force behind expansion of this gene family that underwent purifying selection during evolution. Computational investigation unraveled their intronless organization and identified similar motif composition within the same subfamily. Phylogenetic analyses clustered the PvuGRAS proteins into 16 phylogenetic clades and established extensive orthologous relationships with Arabidopsis and rice. Analysis of the upstream promoter region uncovered cis-elements responsive to growth, development, and abiotic stresses that may account for their differential expression. The identified SSRs could serve as putative molecular markers facilitating future breeding programs. 37 PvuGRAS transcripts were post-transcriptionally regulated by different miRNA families, miR171 being the major player preferentially targeting members of the HAM subfamily. Global expression profile based on RNA-seq data indicates a clade specific expression pattern in various tissues and developmental stages. Additionally, nine PvuGRAS genes were chosen for further qPCR analyses under drought, salt, and cold stress suggesting their involvement in acclimation to environmental stimuli. Combined, the present results significantly contribute to the current understanding of the complexity and biological function of the PvuGRAS gene family. The resources generated will provide a solid foundation in future endeavors for genetic improvement in common bean.
PMID: 34561734
J Proteomics , IF:4.044 , 2021 Sep , V248 : P104349 doi: 10.1016/j.jprot.2021.104349
Proteome analysis reveals a systematic response of cold-acclimated seedlings of an exotic mangrove plant Sonneratia apetala to chilling stress.
Key Laboratory for Subtropical Wetland Ecosystem Research of Ministry of Education, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian 361005, PR China.; Key Laboratory for Subtropical Wetland Ecosystem Research of Ministry of Education, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian 361005, PR China; Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, College of Environment and Resources, Guangxi Normal University, Guilin, Guangxi 541004, PR China.; Fujian Key Laboratory of Subtropical Plant Physiology and Biochemistry, Fujian Institute of Subtropical Botany, Xiamen, Fujian 361006, PR China.; Key Laboratory for Subtropical Wetland Ecosystem Research of Ministry of Education, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian 361005, PR China. Electronic address: zhenghl@xmu.edu.cn.
Low temperature in winter was the most crucial abiotic stress that limits the mangrove afforestation northward. Previous study demonstrated that Sonneratia apetala initially transplanted to high latitude area exhibited a stronger plasticity of cold tolerance. To clarify the underlying mechanism, the physiological and proteomic responses to chilling stress were investigated in S. apetala leaves. Our results found that cold-acclimated seedlings had lower relative electrolyte leakage and MDA content than non-acclimated seedlings. On the contrary, higher chlorophyll content and photosynthetic capacity were observed in cold-acclimated seedlings. With proteomic analyses, the differentially accumulated proteins (DAPs) involved in ROS scavenging, photosynthesis and energy metabolism, carbohydrate metabolism, cofactor biosynthesis, and protein folding were suggested to play important roles in enhancing the cold tolerance of S. apetala. However, the down-regulation DAPs were suggested as a tradeoff between plant growth and chilling response. By the protein-protein interaction analyses, translation elongation factor G, chlorophyll A-B binding protein and ascorbate peroxidase 1 were suggested as the important regulators in cold-acclimated S. apetala seedlings under chilling stress. Based on the above results, a schematic diagram describing the mechanism of cold tolerance of exotic mangrove species S. apetala that was achieved by cold acclimation was presented in this study. SIGNIFICANCE: The major environmental factor limits the mangrove afforestation northward is the low temperature in winter. Previous study reported that Sonneratia apetala grew in high latitude exhibited a higher cold tolerance than that in low latitude, which was suggested as a result of cold acclimation. To further understand "how cold acclimation enhance the cold tolerance in S. apetala", the response of S. apetala subjected to chilling stress with or without cold acclimation was investigated in this study at the physiological and proteomic aspects. Our physiological results showed that S. apetala seedlings treated with cold acclimation exhibited a higher tolerance under chilling stress than that without cold acclimation. By using the comparative proteomic approaches and bioinformatic analyses, various biological processes were suggested to play an important role in enhancing the cold tolerance of S. apetala under chilling stress, such as ROS scavenging, photosynthesis and energy metabolism, carbohydrate metabolism, cofactor biosynthesis, and protein folding. Among these differentially accumulated proteins, translation elongation factor G (eEF-G), chlorophyll A-B binding protein (CAB) and ascorbate peroxidase 1 (APX1) were identified as the hub proteins function in coordinated regulating ROS scavenging, photosynthesis and protein biosynthesis in chloroplast and subsequently enhanced the cold tolerance of S. apetala under chilling stress. Our results provided a further understanding of cold acclimation in improving the cold tolerance in exotic mangrove species S. apetala.
PMID: 34411764
BMC Genomics , IF:3.969 , 2021 Sep , V22 (1) : P681 doi: 10.1186/s12864-021-07998-0
Transcriptome profiling of Malus sieversii under freezing stress after being cold-acclimated.
State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, 830011, China.; University of Chinese Academy of Sciences, Beijing, 100049, China.; Turpan Eremophytes Botanical Garden, Chinese Academy of Sciences, Turpan, 838008, China.; State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, 830011, China. zhangdy@ms.xjb.ac.cn.; Turpan Eremophytes Botanical Garden, Chinese Academy of Sciences, Turpan, 838008, China. zhangdy@ms.xjb.ac.cn.
BACKGROUND: Freezing temperatures are an abiotic stress that has a serious impact on plant growth and development in temperate regions and even threatens plant survival. The wild apple tree (Malus sieversii) needs to undergo a cold acclimation process to enhance its freezing tolerance in winter. Changes that occur at the molecular level in response to low temperatures are poorly understood in wild apple trees. RESULTS: Phytohormone and physiology profiles and transcriptome analysis were used to elaborate on the dynamic response mechanism. We determined that JA, IAA, and ABA accumulated in the cold acclimation stage and decreased during freezing stress in response to freezing stress. To elucidate the molecular mechanisms of freezing stress after cold acclimation, we employed single molecular real-time (SMRT) and RNA-seq technologies to study genome-wide expression profiles in wild apple. Using the PacBio and Illumina platform, we obtained 20.79G subreads. These reads were assembled into 61,908 transcripts, and 24,716 differentially expressed transcripts were obtained. Among them, 4410 transcripts were differentially expressed during the whole process of freezing stress, and these were examined for enrichment via GO and KEGG analyses. Pathway analysis indicated that "plant hormone signal transduction", "starch and sucrose metabolism", "peroxisome" and "photosynthesis" might play a vital role in wild apple responses to freezing stress. Furthermore, the transcription factors DREB1/CBF, MYC2, WRKY70, WRKY71, MYB4 and MYB88 were strongly induced during the whole stress period. CONCLUSIONS: Our study presents a global survey of the transcriptome profiles of wild apple trees in dynamic response to freezing stress after two days cold acclimation and provides insights into the molecular mechanisms of freezing adaptation of wild apple plants for the first time. The study also provides valuable information for further research on the antifreezing reaction mechanism and genetic improvement of M. sieversii after cold acclimation.
PMID: 34548013
Plants (Basel) , IF:3.935 , 2021 Sep , V10 (9) doi: 10.3390/plants10091864
Convergence and Divergence: Signal Perception and Transduction Mechanisms of Cold Stress in Arabidopsis and Rice.
State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Agriculture, Guangxi University, Nanning 530004, China.; MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
Cold stress, including freezing stress and chilling stress, is one of the major environmental factors that limit the growth and productivity of plants. As a temperate dicot model plant species, Arabidopsis develops a capability to freezing tolerance through cold acclimation. The past decades have witnessed a deep understanding of mechanisms underlying cold stress signal perception, transduction, and freezing tolerance in Arabidopsis. In contrast, a monocot cereal model plant species derived from tropical and subtropical origins, rice, is very sensitive to chilling stress and has evolved a different mechanism for chilling stress signaling and response. In this review, the authors summarized the recent progress in our understanding of cold stress response mechanisms, highlighted the convergent and divergent mechanisms between Arabidopsis and rice plasma membrane cold stress perceptions, calcium signaling, phospholipid signaling, MAPK cascade signaling, ROS signaling, and ICE-CBF regulatory network, as well as light-regulated signal transduction system. Genetic engineering approaches of developing freezing tolerant Arabidopsis and chilling tolerant rice were also reviewed. Finally, the future perspective of cold stress signaling and tolerance in rice was proposed.
PMID: 34579397
Gene , IF:3.688 , 2021 Sep , V807 : P145952 doi: 10.1016/j.gene.2021.145952
Identification of key genes and molecular mechanisms associated with temperature stress in lentil.
Department of Plant Production and Genetic Engineering, Faculty of Agriculture, Lorestan University, Khorramabad, Iran. Electronic address: sohrabi.sa@fa.lu.ac.ir.; Department of Plant Production and Genetic Engineering, Faculty of Agriculture, Lorestan University, Khorramabad, Iran. Electronic address: ismaili.a@lu.ac.ir.; Department of Plant Production and Genetic Engineering, Faculty of Agriculture, Lorestan University, Khorramabad, Iran. Electronic address: nazarian.f@lu.ac.ir.; Department of Biology, School of Sciences, Razi University, Kermanshah, Iran. Electronic address: h.fallahi@razi.ac.ir.; Department of Plant Production and Genetic Engineering, Faculty of Agriculture, Lorestan University, Khorramabad, Iran. Electronic address: hoseini.za@fa.lu.ac.ir.
Extreme temperature is one of the serious threats to crop production in present and future scenarios of global climate changes. Lentil (Lens culinaris) is an important crop, and there is a serious lack of genetic information regarding environmental and temperature stresses responses. This study is the first report of evaluation of key genes and molecular mechanisms related to temperature stresses in lentil using the RNA sequencing technique. De novo transcriptome assembly created 44,673 contigs and differential gene expression analysis revealed 7494 differentially expressed genes between the temperature stresses and control group. Basic annotation of generated transcriptome assembly in our study led to the identification of 2765 novel transcripts that have not been identified yet in lentil genome draft v1.2. In addition, several unigenes involved in mechanisms of temperature sensing, calcium and hormone signaling and DNA-binding transcription factor activity were identified. Also, common mechanisms in response to temperature stresses, including the proline biosynthesis, the photosynthetic light reactions balancing, chaperone activity and circadian rhythms, are determined by the hub genes through the protein-protein interaction networks analysis. Deciphering the mechanisms of extreme temperature tolerance would be a new way for developing crops with enhanced plasticity against climate change. In general, this study has identified set of mechanisms and various genes related to cold and heat stresses which will be useful in better understanding of the lentil's reaction to temperature stresses.
PMID: 34500049
Biochem Biophys Res Commun , IF:3.575 , 2021 Sep , V568 : P124-130 doi: 10.1016/j.bbrc.2021.06.081
Disulfide reductase activity of thioredoxin-h2 imparts cold tolerance in Arabidopsis.
Division of Applied Life Science (BK21(+)) and PMBBRC, Gyeongsang National University, Jinju, 52828, South Korea.; Division of Applied Life Science (BK21(+)) and PMBBRC, Gyeongsang National University, Jinju, 52828, South Korea. Electronic address: sylee@gnu.ac.kr.
Many thioredoxin-h (Trx-h) proteins, cytosolic isotypes of Trxs, have been functionally characterized in plants; however, the physiological function of Arabidopsis Trx-h2, which harbors two active site cysteine (Cys) residues and an N-terminal extension peptide containing a fatty acid acylation site, remains unclear. In this study, we investigated the physiological function of Trx-h2 by performing several abiotic stress treatments using trx-h1-3 knockout mutant lines, and found that the reductase function of Trx-h2 is critical for cold resistance in Arabidopsis. Plants overexpressing Trx-h2 in the trx-h2 mutant background (Trx-h2(OE)/trx-h2) showed strong cold tolerant phenotypes compared with Col-0 (wild type) and trx-h2 mutant plants. By contrast, Trx-h2(C/S)(OE)/trx-h2 plants expressing a variant Trx-h2 protein, in which both active site Cys residues were substituted by serine (Ser) residues, showed high cold sensitivity, similar to trx-h2 plants. Moreover, cold-responsive (COR) genes were highly up-regulated in Trx-h2(OE)/trx-h2 plants but not in trx-h2 and Trx-h2(C/S)(OE)/trx-h2 plants under cold conditions. These results explicitly suggest that the cytosolic Trx-h2 protein relays the external cold stress signal to downstream cold defense signaling cascades through its protein disulfide reductase function.
PMID: 34217011
J Appl Genet , IF:3.24 , 2021 Sep doi: 10.1007/s13353-021-00660-1
Quantitative trait loci and candidate genes associated with freezing tolerance of winter triticale (x Triticosecale Wittmack).
Institute of Biology, Pedagogical University of Cracow, Podchorazych 2, 30-084, Krakow, Poland.; Institute of Biology, Pedagogical University of Cracow, Podchorazych 2, 30-084, Krakow, Poland. gabriela.golebiowska@up.krakow.pl.; Department of Biotechnology and Bioinformatics, Faculty of Chemistry, Rzeszow University of Technology, Powstancow Warszawy 6, 35-959, Rzeszow, Poland.; Department of Plant Breeding, Physiology and Seed Science, University of Agriculture in Krakow, Podluzna 3, 30-239, Krakow, Poland.; Plant Breeding and Acclimatization Institute, National Research Institute, 05-870, Radzikow, Blonie, Poland.; The Franciszek Gorski Institute of Plant Physiology, Polish Academy of Sciences, Krakow, Poland.
Freezing tolerance of triticale is a major trait contributing to its winter hardiness. The identification of genomic regions - quantitative trait loci (QTL) and molecular markers associated with freezing tolerance in winter hexaploid triticale - was the aim of this study. For that purpose, a new genetic linkage map was developed for the population of 92 doubled haploid lines derived from 'Hewo' x 'Magnat' F1 hybrid. Those lines, together with parents were subjected to freezing tolerance test three times during two winter seasons. Plants were grown and cold-hardened under natural fall/winter conditions and then subjected to freezing in controlled conditions. Freezing tolerance was assessed as the plants recovery (REC), the electrolyte leakage (EL) from leaves and chlorophyll fluorescence parameters (JIP) after freezing. Three consistent QTL for several fluorescence parameters, electrolyte leakage, and the percentage of the survived plants were identified with composite interval mapping (CIM) and single marker analysis (SMA). The first locus Qfr.hm-7A.1 explained 9% of variation of both electrolyte leakage and plants recovery after freezing. Two QTL explaining up to 12% of variation in plants recovery and shared by selected chlorophyll fluorescence parameters were found on 4R and 5R chromosomes. Finally, main locus Qchl.hm-5A.1 was detected for chlorophyll fluorescence parameters that explained up to 19.6% of phenotypic variation. The co-located QTL on chromosomes 7A.1, 4R and 5R, clearly indicated physiological and genetic relationship of the plant survival after freezing with the ability to maintain optimal photochemical activity of the photosystem II and preservation of the cell membranes integrity. The genes located in silico within the identified QTL include those encoding BTR1-like protein, transmembrane helix proteins like potassium channel, and phosphoric ester hydrolase involved in response to osmotic stress as well as proteins involved in the regulation of the gene expression, chloroplast RNA processing, and pyrimidine salvage pathway. Additionally, our results confirm that the JIP test is a valuable tool to evaluate freezing tolerance of triticale under unstable winter environments.
PMID: 34491554
G3 (Bethesda) , IF:3.154 , 2021 Sep , V11 (9) doi: 10.1093/g3journal/jkab196
Rice TSV2 encoding threonyl-tRNA synthetase is needed for early chloroplast development and seedling growth under cold stress.
College of Life Sciences, Shanghai Normal University, Shanghai 200234, China.; Crop Institute, Taizhou Academy of Agricultural Sciences, Zhejiang Linhai 317000, China.; Shanghai Key Laboratory of Plant Molecular Sciences, Shanghai 200234, China.; Institute of Genetics, Shanghai Normal University, Shanghai 200234, China.
Threonyl-tRNA synthetase (ThrRS), one of the aminoacyl-tRNA synthetases (AARSs), plays a crucial role in protein synthesis. However, the AARS functions on rice chloroplast development and growth were not fully appraised. In this study, a thermo-sensitive virescent mutant tsv2, which showed albino phenotype and lethal after the 4-leaf stage at 20 degrees C but recovered to normal when the temperatures rose, was identified and characterized. Map-based cloning and complementation tests showed that TSV2 encoded a chloroplast-located ThrRS protein in rice. The Lys-to-Arg mutation in the anticodon-binding domain hampered chloroplast development under cold stress, while the loss of function of the ThrRS core domain in TSV2 fatally led to seedling death regardless of growing temperatures. In addition, TSV2 had a specific expression in early leaves. Its disruption obviously resulted in the downregulation of certain genes associated with chlorophyll biosynthesis, photosynthesis, and chloroplast development at cold conditions. Our observations revealed that rice nuclear-encoded TSV2 plays an important role in chloroplast development at the early leaf stage under cold stress.
PMID: 34544147
G3 (Bethesda) , IF:3.154 , 2021 Sep , V11 (9) doi: 10.1093/g3journal/jkab198
The Brachypodium distachyon cold-acclimated plasma membrane proteome is primed for stress resistance.
Department of Biology, Queen's University, Kingston, ON K7L 3N6, Canada.; Department of Plant-Bioscience, Faculty of Agriculture, Iwate University, Morioka, Iwate 020-8550, Japan.; United Graduate School of Agricultural Sciences, Iwate University, Morioka, Iwate 020-8550, Japan.; Department of Biomedical and Molecular Sciences, School of Environmental Studies, Queen's University, Kingston, ON K7L 3N6, Canada.
In order to survive subzero temperatures, some plants undergo cold acclimation (CA) where low, nonfreezing temperatures, and/or shortened day lengths allow cold-hardening and survival during subsequent freeze events. Central to this response is the plasma membrane (PM), where low temperature is perceived and cellular homeostasis must be preserved by maintaining membrane integrity. Here, we present the first PM proteome of cold-acclimated Brachypodium distachyon, a model species for the study of monocot crops. A time-course experiment investigated CA-induced changes in the proteome following two-phase partitioning PM enrichment and label-free quantification by nano-liquid chromatography-mass spectrophotometry. Two days of CA were sufficient for membrane protection as well as an initial increase in sugar levels and coincided with a significant change in the abundance of 154 proteins. Prolonged CA resulted in further increases in soluble sugars and abundance changes in more than 680 proteins, suggesting both a necessary early response to low-temperature treatment, as well as a sustained CA response elicited over several days. A meta-analysis revealed that the identified PM proteins have known roles in low-temperature tolerance, metabolism, transport, and pathogen defense as well as drought, osmotic stress, and salt resistance suggesting crosstalk between stress responses, such that CA may prime plants for other abiotic and biotic stresses. The PM proteins identified here present keys to an understanding of cold tolerance in monocot crops and the hope of addressing economic losses associated with modern climate-mediated increases in frost events.
PMID: 34544140
Plant Signal Behav , IF:2.247 , 2021 Sep : P1973711 doi: 10.1080/15592324.2021.1973711
Salicylic acid induces tolerance of VitisripariaxV.labrusca to chilling stress by altered photosynthetic, antioxidant mechanisms and expression of cold stress responsive genes.
College of Life Science and Technology,Gansu Agricultural University,Lanzhou,China.; Key Laboratory of Arid Land Crop Science of Gansu Province, College of Life Science and Technology,Gansu Agricultural University,Lanzhou,China.
The yield and quality of wine grapes are severely persecuted by low-temperaturestresses. Salicylic acid (SA) assists plants in coping with abiotic stresses such as drought, heavy metal toxicity, and osmotic stress. The objective of this study was to evaluate the effect of foliar spraying of different concentrations of SA on the mitigation of cold damage in grapes, which is useful for the cultivation of wine grapes.VitisripariaxV.labruscaseedlings were treated with foliar-sprayedSA at concentrations of 0-2 mM and then subjected to chilling stress at 4 degrees C for 2 or 4 days, while the expression of relevant physiological indicators and cold response genes (CBF1, CBF2, CBF3) were measured. The findings indicated that low temperature stresses markedly reduced chlorophyll content, and increased proline as well as soluble sugar content, enhanced superoxide dismutase (SOD) and peroxidase (POD) activities, decreased catalase (CAT) activity and inducedCBFgene expression in leaves. Physiologically, foliar spraying of different concentrations of SA greatly increased antioxidant enzyme activity (P < .05), soluble sugars, proline, and chlorophyll content of grapes leave under low temperature stress. With regard to gene expression, SA has significantly regulated the cold response genesCBF1, CBF2, andCBF3. Therefore, SA could reduce cold damage in grapevines under low-temperaturestress, and the effect of SA was most pronounced in the 1 and 2 mM concentrates.
PMID: 34523393
Genes Genomics , IF:1.839 , 2021 Oct , V43 (10) : P1209-1222 doi: 10.1007/s13258-021-01143-7
Overexpression of antisense phosphatase 2C affords cold resistance in hybrid Populus davidiana x Populus bolleana.
Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, Northest Forestry University, No. 26 Hexing Road Xiangfang District, Harbin, 150040, P.R. China.; Environmental Biotechnology Laboratory, Department of Biotechnology, University of Azad Jammu and Kashmir, Chehla Campus, Muzaffarabad, 13100, Azad Kashmir, Pakistan.; Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, Northest Forestry University, No. 26 Hexing Road Xiangfang District, Harbin, 150040, P.R. China. guanqingjie@nefu.edu.cn.
BACKGROUND: Overexpression of the abiotic and biotic stress-resistance genes of the plant signaling pathway is well known for its significant role in the regulation of plant growth and enhancement of the productivity of agricultural land under changing climatic conditions. OBJECTIVES: This research aimed to clone Populus davidiana x Populus bolleana PP2C (PdPP2C) gene and analyze its structure and function, and downregulate PdPP2C by overexpression of its antisense PdPP2C (AS-PdPP2C) gene for enhancing cold resistance in transgenic lines of hybrid P. davidiana x P. bolleana. METHODS: PdPP2C was cloned and transformed to identify its function, and its antisense was overexpressed via downregulation to increase the cold resistance in transgenic lines of hybrid P. davidiana x P. bolleana. RESULTS: Antisense inhibition of protein phosphatase 2C accelerates the cold acclimation of Poplar (P. davidiana x P. bolleana) gene in terms of antifreeze. CONCLUSION: PdPP2C was expressed in the roots, stems, and leaves of P. davidiana x P. bolleana, and the expression was higher in the leaves. The expression of PdPP2C was also significantly downregulated at low-temperature (0 degrees C and 4 degrees C) stress. The relative conductivity and malondialdehyde content of non-transgenic lines were higher than those of AS-PdPP2C lines after 2 days of cold treatment at - 1 degrees C. The leaves of the transgenic lines were not wilted and showed no chlorosis compared with those of the non-transgenic lines. The AS-PdPP2C transgenic lines also showed higher freezing resistance than the non-transgenic lines. AS-PdPP2C participated in the regulation of freezing resistance.
PMID: 34338987
Plant Phenomics , 2021 , V2021 : P9895241 doi: 10.34133/2021/9895241
Exploring Seasonal and Circadian Rhythms in Structural Traits of Field Maize from LiDAR Time Series.
Plant Phenomics Research Centre, Academy for Advanced Interdisciplinary Studies, Collaborative Innovation Centre for Modern Crop Production Co-Sponsored by Province and Ministry, Jiangsu Key Laboratory for Information Agriculture, Nanjing Agricultural University, Nanjing 210095, China.; Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology, International Institute for Earth System Sciences, Nanjing University, Nanjing, Jiangsu 210023, China.; State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.; University of Chinese Academy of Sciences, Beijing 100049, China.; National Technique Innovation Center for Regional Wheat Production/Key Laboratory of Crop Ecophysiology, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, 210095 Jiangsu, China.; Department of Forestry, Mississippi State University, Mississippi State 39759, USA.; Environnement Mediterraneen et Modelisation des Agro-Hydrosystemes (EMMAH), Institut National de la Recherche Agronomique, Unite Mixte de Recherche 1114 Domaine Saint-Paul, Avignon Cedex 84914, France.; Department of Ecology, College of Environmental Sciences, and Key Laboratory of Earth Surface Processes of the Ministry of Education, Peking University, Beijing 100871, China.
Plant growth rhythm in structural traits is important for better understanding plant response to the ever-changing environment. Terrestrial laser scanning (TLS) is a well-suited tool to study structural rhythm under field conditions. Recent studies have used TLS to describe the structural rhythm of trees, but no consistent patterns have been drawn. Meanwhile, whether TLS can capture structural rhythm in crops is unclear. Here, we aim to explore the seasonal and circadian rhythms in maize structural traits at both the plant and leaf levels from time-series TLS. The seasonal rhythm was studied using TLS data collected at four key growth periods, including jointing, bell-mouthed, heading, and maturity periods. Circadian rhythms were explored by using TLS data acquired around every 2 hours in a whole day under standard and cold stress conditions. Results showed that TLS can quantify the seasonal and circadian rhythm in structural traits at both plant and leaf levels. (1) Leaf inclination angle decreased significantly between the jointing stage and bell-mouthed stage. Leaf azimuth was stable after the jointing stage. (2) Some individual-level structural rhythms (e.g., azimuth and projected leaf area/PLA) were consistent with leaf-level structural rhythms. (3) The circadian rhythms of some traits (e.g., PLA) were not consistent under standard and cold stress conditions. (4) Environmental factors showed better correlations with leaf traits under cold stress than standard conditions. Temperature was the most important factor that significantly correlated with all leaf traits except leaf azimuth. This study highlights the potential of time-series TLS in studying outdoor agricultural chronobiology.
PMID: 34557676