Nat Commun , IF:12.121 , 2020 Mar , V11 (1) : P1592 doi: 10.1038/s41467-020-15394-7
Modulation of BIN2 kinase activity by HY5 controls hypocotyl elongation in the light.
State Key Laboratory of Protein and Plant Gene Research, School of Advanced Agricultural Sciences and School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, 100871, Beijing, China.; Institute of Plant and Food Science, Department of Biology, Southern University of Science and Technology, 518055, Shenzhen, China.; Department of Biology, Wilkes University, Wilkes-Barre, PA, 18766, USA.; Institute for Mathematical Sciences, Renmin University of China, 100872, Beijing, China. xinqigong@ruc.edu.cn.; State Key Laboratory of Protein and Plant Gene Research, School of Advanced Agricultural Sciences and School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, 100871, Beijing, China. zhudanmeng@pku.edu.cn.; State Key Laboratory of Protein and Plant Gene Research, School of Advanced Agricultural Sciences and School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, 100871, Beijing, China. deng@pku.edu.cn.; Institute of Plant and Food Science, Department of Biology, Southern University of Science and Technology, 518055, Shenzhen, China. deng@pku.edu.cn.
ELONGATED HYPOCOTYL 5 (HY5), a basic domain/leucine zipper (bZIP) transcription factor, acts as a master regulator of transcription to promote photomorphogenesis. At present, it's unclear whether HY5 uses additional mechanisms to inhibit hypocotyl elongation. Here, we demonstrate that HY5 enhances the activity of GSK3-like kinase BRASSINOSTEROID-INSENSITIVE 2 (BIN2), a key repressor of brassinosteroid signaling, to repress hypocotyl elongation. We show that HY5 physically interacts with and genetically acts through BIN2 to inhibit hypocotyl elongation. The interaction of HY5 with BIN2 enhances its kinase activity possibly by the promotion of BIN2 Tyr(200) autophosphorylation, and subsequently represses the accumulation of the transcription factor BRASSINAZOLE-RESISTANT 1 (BZR1). Leu(137) of HY5 is found to be important for the HY5-BIN2 interaction and HY5-mediated regulation of BIN2 activity, without affecting the transcriptional activity of HY5. HY5 levels increase with light intensity, which gradually enhances BIN2 activity. Thus, our work reveals an additional way in which HY5 promotes photomorphogenesis, and provides an insight into the regulation of GSK3 activity.
PMID: 32221308
New Phytol , IF:8.512 , 2020 Mar , V225 (6) : P2439-2452 doi: 10.1111/nph.16301
A basic helix-loop-helix protein (GhFP1) promotes fibre elongation of cotton (Gossypium hirsutum) by modulating brassinosteroid biosynthesis and signalling.
Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China.; School of Life Sciences, Hubei Normal University, Huangshi, 435002, China.
Basic helix-loop-helix (bHLH) proteins are involved in transcriptional networks controlling a number of biological processes in plants. However, little information is known on the roles of bHLH proteins in cotton fibre development so far. Here, we show that a cotton bHLH protein (GhFP1) positively regulates fibre elongation. GhFP1 transgenic cotton and Arabidopsis plants were generated to study how GhFP1 regulates fibre cell elongation. Fibre length of the transgenic cotton overexpressing GhFP1 was significantly longer than that of wild-type, whereas suppression of GhFP1 expression hindered fibre elongation. Furthermore, overexpression of GhFP1 in Arabidopsis promoted trichome development. Expression of the brassinosteroid (BR)-related genes was markedly upregulated in fibres of GhFP1 overexpression cotton, but downregulated in GhFP1-silenced fibres. BR content in the transgenic fibres was significantly altered, relative to that in wild-type. Moreover, GhFP1 protein could directly bind to the promoters of GhDWF4 and GhCPD to activate expression of these BR-related genes. Therefore, our data suggest that GhFP1 as a positive regulator participates in controlling fibre elongation by activating BR biosynthesis and signalling. Additionally, homodimerisation of GhFP1 may be essential for its function, and interaction between GhFP1 and other cotton bHLH proteins may interfere with its DNA-binding activity.
PMID: 31667846
Int J Mol Sci , IF:4.556 , 2020 Mar , V21 (6) doi: 10.3390/ijms21062090
The Rice Basic Helix-Loop-Helix 79 (OsbHLH079) Determines Leaf Angle and Grain Shape.
Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea.; Department of Plant Molecular Systems Biotechnology, Crop Biotech Institute, Kyung Hee University, Yongin 17104, Korea.
Changes in plant architecture, such as leaf size, leaf shape, leaf angle, plant height, and floral organs, have been major factors in improving the yield of cereal crops. Moreover, changes in grain size and weight can also increase yield. Therefore, screens for additional factors affecting plant architecture and grain morphology may enable additional improvements in yield. Among the basic Helix-Loop-Helix (bHLH) transcription factors in rice (Oryza sativa), we found an enhancer-trap T-DNA insertion mutant of OsbHLH079 (termed osbhlh079-D). The osbhlh079-D mutant showed a wide leaf angle phenotype and produced long grains, similar to the phenotypes of mutants with increased brassinosteroid (BR) levels or enhanced BR signaling. Reverse transcription-quantitative PCR analysis showed that BR signaling-associated genes are largely upregulated in osbhlh079-D, but BR biosynthesis-associated genes are not upregulated, compared with its parental japonica cultivar 'Dongjin'. Consistent with this, osbhlh079-D was hypersensitive to BR treatment. Scanning electron microscopy revealed that the expansion of cell size in the adaxial side of the lamina joint was responsible for the increase in leaf angle in osbhlh079-D. The expression of cell-elongation-associated genes encoding expansins and xyloglucan endotransglycosylases/hydrolases increased in the lamina joints of leaves in osbhlh079-D. The regulatory function of OsbHLH079 was further confirmed by analyzing 35S::OsbHLH079 overexpression and 35S::RNAi-OsbHLH079 gene silencing lines. The 35S::OsbHLH079 plants showed similar phenotypes to osbhlh079-D, and the 35S::RNAi-OsbHLH079 plants displayed opposite phenotypes to osbhlh079-D. Taking these observations together, we propose that OsbHLH079 functions as a positive regulator of BR signaling in rice.
PMID: 32197452
Int J Mol Sci , IF:4.556 , 2020 Mar , V21 (5) doi: 10.3390/ijms21051889
HSP Transcript and Protein Accumulation in Brassinosteroid Barley Mutants Acclimated to Low and High Temperatures.
Polish Academy of Sciences, The Franciszek Gorski Institute of Plant Physiology, Niezapominajek 21, 30-239 Krakow, Poland.; Department of Plant Physiology, University of Agriculture in Krakow, Podluzna 3, 30-239 Krakow, Poland.; Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia, Jagiellonska 28, 40-032 Katowice, Poland.
In temperature stress, the main role of heat-shock proteins (HSP) is to act as molecular chaperones for other cellular proteins. However, knowledge about the hormonal regulation of the production of the HSP is quite limited. Specifically, little is known about the role of the plant steroid hormones-brassinosteroids (BR)-in regulating the HSP expression. The aim of our study was to answer the question of how a BR deficit or disturbances in its signaling affect the accumulation of the HSP90, HSP70, HSP18, and HSP17 transcripts and protein in barley growing at 20 degrees C (control) and during the acclimation of plants at 5 degrees C and 27 degrees C. In barley, the temperature of plant growth modified the expression of HSPs. Furthermore, the BR-deficient mutants (mutations in the HvDWARF or HvCPD genes) and BR-signaling mutants (mutation in the HvBRI1 gene) were characterized by altered levels of the transcripts and proteins of the HSP group compared to the wild type. The BR-signaling mutant was characterized by a decreased level of the HSP transcripts and heat-shock proteins. In the BR-deficient mutants, there were temperature-dependent cases when the decreased accumulation of the HSP70 and HSP90 transcripts was connected to an increased accumulation of these HSP. The significance of changes in the accumulation of HSPs during acclimation at 27 degrees C and 5 degrees C is discussed in the context of the altered tolerance to more extreme temperatures of the studied mutants (i.e., heat stress and frost, respectively).
PMID: 32164259
Int J Mol Sci , IF:4.556 , 2020 Mar , V21 (5) doi: 10.3390/ijms21051832
Biological Activities and Molecular Docking of Brassinosteroids 24-Norcholane Type Analogs.
Departamento de Quimica, Universidad Tecnica Federico Santa Maria, Avenida Espana 1680, Valparaiso 2340000, Chile.; Center for Natural Products Research, Faculty of Chemistry, University of Havana. Zapata y G, La Habana 10400, Cuba.; Instituto de Ciencias Quimicas Aplicadas, Facultad de Ingenieria, Universidad Autonoma de Chile, El Llano Subercaseaux 2801, Santiago 8900000, Chile.
The quest and design of new brassinosteroids analogs is a matter of current interest. Herein, the effect of short alkyl side chains and the configuration at C22 on the growth-promoting activity of a series of new brassinosteroid 24-norcholan-type analogs have been evaluated by the rice leaf inclination test using brassinolide as positive control. The highest activities were found for triol 3 with a C22(S) configuration and monobenzoylated derivatives. A docking study of these compounds into the active site of the Brassinosteroid Insensitive 1(BRI1)-ligand-BRI1-Associated Receptor Kinase 1 (BAK1) complex was performed using AutoDock Vina, and protein-ligand contacts were analyzed using LigPlot(+). The results suggest that the hydrophobic interactions of ligands with the receptor BRI1(LRR) and hydrogen bonding with BAK1 in the complex are important for ligand recognition. For monobenzoylated derivatives, the absence of the hydrophobic end in the alkyl chain seems to be compensated by the benzoyl group. Thus, it would be interesting to determine if this result depends on the nature of the substituent group. Finally, mixtures of S/R triols 3/4 exhibit activities that are comparable or even better than those found for brassinolide. Thus, these compounds are potential candidates for application in agriculture to improve the growth and yield of plants against various types of biotic and abiotic stress.
PMID: 32155857
Int J Mol Sci , IF:4.556 , 2020 Mar , V21 (5) doi: 10.3390/ijms21051743
The Control of Cell Expansion, Cell Division, and Vascular Development by Brassinosteroids: A Historical Perspective.
Department of Biological Sciences, College of Biological Sciences and Biotechnology, Chungnam National University, Daejeon 34134, Korea.; Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85721, USA.
Steroid hormones are important signaling molecules in plants and animals. The plant steroid hormone brassinosteroids were first isolated and characterized in the 1970s and have been studied since then for their functions in plant growth. Treatment of plants or plant cells with brassinosteroids revealed they play important roles during diverse developmental processes, including control of cell expansion, cell division, and vascular differentiation. Molecular genetic studies, primarily in Arabidopsis thaliana, but increasingly in many other plants, have identified many genes involved in brassinosteroid biosynthesis and responses. Here we review the roles of brassinosteroids in cell expansion, cell division, and vascular differentiation, comparing the early physiological studies with more recent results of the analysis of mutants in brassinosteroid biosynthesis and signaling genes. A few representative examples of other molecular pathways that share developmental roles with brassinosteroids are described, including pathways that share functional overlap or response components with the brassinosteroid pathway. We conclude by briefly discussing the origin and conservation of brassinosteroid signaling.
PMID: 32143305
Plant Sci , IF:3.591 , 2020 Mar , V292 : P110378 doi: 10.1016/j.plantsci.2019.110378
Overexpression of a maize BR transcription factor ZmBZR1 in Arabidopsis enlarges organ and seed size of the transgenic plants.
Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China.; Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China. Electronic address: puli@caas.cn.; Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China. Electronic address: zhangchunyi@caas.cn.
In plants, the organ size is one of the most important features and regulated by an elaborate developmental program involving both internal and external signals. The steroidal hormone brassinosteroid (BR) plays an important role in regulating the organ size. BRASSINAZOLE RESISTANT 1 (BZR1) is one of important transcription factors that regulate organ size in BR signal pathway in Arabidopsis. The function of BZR1 on organ size is well characterized in Arabidopsis, but poorly understood in maize (Zea mays). To understand the mechanism of intrinsic organ size regulated by BZR1 during organogenesis, we identified the maize BZR1 and examined its function in Arabidopsis. Overexpression of ZmBZR1 displayed phenotypes of enlarged cotyledons, rosette leaves, floral organ and seed size in Arabidopsis. The cells in rosette leaves as well as other organs in transgenic ZmBZR1 lines were dramatically larger and longer than those in Col-0. ChIP and RNA-seq analysis showed ZmBZR1 can directly bind to the promoter region of organ size related genes, Germination Repression and Cell Expansion receptor-like kinase (GRACE) and KIP-RELATED PROTEIN6 (KRP6) to regulate their expression, suggesting ZmBZR1 is required for the progressive increase in cells during Arabidopsis development. Collectively, our findings provide significant insights into the mechanisms underlying regulation of organ size mediated by maize BZR1.
PMID: 32005383
BMC Plant Biol , IF:3.497 , 2020 Mar , V20 (1) : P109 doi: 10.1186/s12870-020-2323-8
PcDWF1, a pear brassinosteroid biosynthetic gene homologous to AtDWARF1, affected the vegetative and reproductive growth of plants.
College of Horticulture, Qingdao Agricultural University, No. 700 Changcheng Road, Qingdao, 266109, China.; Qingdao Key Laboratory of Genetic Improvement and Breeding in Horticulture Plants, Qingdao, 266109, China.; College of Horticulture, Qingdao Agricultural University, No. 700 Changcheng Road, Qingdao, 266109, China. chw6068@126.com.; Qingdao Key Laboratory of Genetic Improvement and Breeding in Horticulture Plants, Qingdao, 266109, China. chw6068@126.com.
BACKGROUND: The steroidal hormones brassinosteroids (BRs) play important roles in plant growth and development. The pathway and genes involved in BR biosynthesis have been identified primarily in model plants like Arabidopsis, but little is known about BR biosynthesis in woody fruits such as pear. RESULTS: In this study, we found that applying exogenous brassinolide (BL) could significantly increase the stem growth and rooting ability of Pyrus ussuriensis. PcDWF1, which had a significantly lower level of expression in the dwarf-type pear than in the standard-type pear, was cloned for further analysis. A phylogenetic analysis showed that PcDWF1 was a pear brassinosteroid biosynthetic gene that was homologous to AtDWARF1. The subcellular localization analysis indicated that PcDWF1 was located in the plasma membrane. Overexpression of PcDWF1 in tobacco (Nicotiana tabacum) or pear (Pyrus ussuriensis) plants promoted the growth of the stems, which was caused by a larger cell size and more developed xylem than those in the control plants, and the rooting ability was significantly enhanced. In addition to the change in vegetative growth, the tobacco plants overexpressing PcDWF1 also had a delayed flowering time and larger seed size than did the control tobacco plants. These phenotypes were considered to result from the higher BL contents in the transgenic lines than in the control tobacco and pear plants. CONCLUSIONS: Taken together, these results reveal that the pear BR biosynthetic gene PcDWF1 affected the vegetative and reproductive growth of Pyrus ussuriensis and Nicotiana tabacum and could be characterized as an important BR biosynthetic gene in perennial woody fruit plants.
PMID: 32143576
BMC Plant Biol , IF:3.497 , 2020 Mar , V20 (1) : P101 doi: 10.1186/s12870-020-2308-7
Graphene oxide and indole-3-acetic acid cotreatment regulates the root growth of Brassica napus L. via multiple phytohormone pathways.
Hubei Key Laboratory of Waterlogging Disaster and Agricultural Use of Wetland, College of Life Science, Yangtze University, Jingzhou, Hubei, 434025, P.R. China.; Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan, Hubei, 430062, P.R. China.; Hubei Provincial Seed Management Bureau, Wuhan, Hubei, 430070, P.R. China.; School of Life and Science Technology, Hubei Engineering University, Xiaogan, Hubei, 432000, P.R. China.; Hubei Key Laboratory of Waterlogging Disaster and Agricultural Use of Wetland, College of Life Science, Yangtze University, Jingzhou, Hubei, 434025, P.R. China. benboxu@yangtzeu.edu.cn.
BACKGROUND: Studies have indicated that graphene oxide (GO) could regulated Brassica napus L. root growth via abscisic acid (ABA) and indole-3-acetic acid (IAA). To study the mechanism and interaction between GO and IAA further, B. napus L (Zhongshuang No. 9) seedlings were treated with GO and IAA accordance with a two factor completely randomized design. RESULTS: GO and IAA cotreatment significantly regulated the root length, number of adventitious roots, and contents of IAA, cytokinin (CTK) and ABA. Treatment with 25 mg/L GO alone or IAA (> 0.5 mg/L) inhibited root development. IAA cotreatment enhanced the inhibitory role of GO, and the inhibition was strengthened with increased in IAA concentration. GO treatments caused oxidative stress in the plants. The ABA and CTK contents decreased; however, the IAA and gibberellin (GA) contents first increased but then decreased with increasing IAA concentration when IAA was combined with GO compared with GO alone. The 9-cis-epoxycarotenoid dioxygenase (NCED) transcript level strongly increased when the plants were treated with GO. However, the NCED transcript level and ABA concentration gradually decreased with increasing IAA concentration under GO and IAA cotreatment. GO treatments decreased the transcript abundance of steroid 5-alpha-reductase (DET2) and isochorismate synthase 1 (ICS), which are associated with brassinolide (BR) and salicylic acid (SA) biosynthesis, but increased the transcript abundance of brassinosteroid insensitive 1-associated receptor kinase 1 (BAK1), cam-binding protein 60-like G (CBP60) and calmodulin binding protein-like protein 1, which are associated with BR and SA biosynthesis. Last, GO treatment increased the transcript abundance of 1-aminocyclopropane-1-carboxylic acid synthase 2 (ACS2), which is associated with the ethylene (ETH) pathway. CONCLUSIONS: Treatment with 25 mg/L GO or IAA (> 0.5 mg/L) inhibited root development. However, IAA and GO cotreatment enhanced the inhibitory role of GO, and this inhibition was strengthened with increased IAA concentration. IAA is a key factor in the response of B. napus L to GO and the responses of B. napus to GO and IAA cotreatment involved in multiple pathways, including those involving ABA, IAA, GA, CTK, BR, SA. Specifically, GO and IAA cotreatment affected the GA content in the modulation of B. napus root growth.
PMID: 32138661
Mol Genet Genomics , IF:2.797 , 2020 Mar , V295 (2) : P343-356 doi: 10.1007/s00438-019-01626-z
A novel single-base mutation in CaBRI1 confers dwarf phenotype and brassinosteroid accumulation in pepper.
Longping Branch of Central South University, Changsha, 410083, China.; Vegetable Institution of Hunan Academy of Agricultural Science, Changsha, 410125, China.; Longping Branch of Central South University, Changsha, 410083, China. zouxuexiao428@163.com.; Vegetable Institution of Hunan Academy of Agricultural Science, Changsha, 410125, China. zouxuexiao428@163.com.
Dwarfing is the development trend of pepper breeding. It is of great practical and scientific value to generate new dwarf germplasms, and identify new genes or alleles conferring dwarf traits in pepper. In our previous study, a weakly BR-insensitive dwarf mutant, E29, was obtained by EMS mutagenesis of the pepper inbred line 6421. It can be used as a good parent material for breeding new dwarf varieties. Here, we found that this dwarf phenotype was controlled by a single recessive gene. Whole-genome resequencing, dCAPs analysis, and VIGs validation revealed that this mutation was caused by a nonsynonymous single-nucleotide mutation (C to T) in CaBRI1. An enzyme activity assay, transcriptome sequencing, and BL content determination further revealed that an amino-acid change (Pro1157Ser) in the serine/threonine protein kinase and catalytic (S_TKc) domain of CaBRI1 impaired its kinase activity and caused the transcript levels of two important genes (CaDWF4 and CaROT3) participating in BR biosynthesis to increase dramatically in the E29 mutant, accompanied by significantly increased accumulation of brassinolide (BL). Therefore, we concluded that the novel single-base mutation in CaBRI1 conferred the dwarf phenotype and resulted in brassinosteroid (BR) accumulation in pepper. This study provides a new allelic variant of the height-regulating gene CaBRI1 that has theoretical and practical values for the breeding of the plants suitable for the facility cultivation and mechanized harvesting of pepper varieties.
PMID: 31745640
Plant Biol (Stuttg) , IF:2.167 , 2020 Mar , V22 (2) : P309-316 doi: 10.1111/plb.13074
Brassinosteroids are involved in ethylene-induced Pst DC3000 resistance in Nicotiana benthamiana.
Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, Sichuan, China.; Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education), China West Normal University, Nanchong, Sichuan, China.; Ecological Security and Protection Key Laboratory of Sichuan Province and Life Science and Technology College, Mianyang Normal University, Mianyang, Sichuan, China.; Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou, Hainan, China.
Plant immunity is regulated by a huge phytohormone regulation network. Ethylene(ET) and brassinosteroids (BRs) play critical roles in plant response to biotic stress; however, the relationship between BR and ET in plant immunity is unclear. We used chemical treatments, genetic approaches and inoculation experiments to investigate the relationship between ET and BR in plant defense against Pst DC3000 in Nicotiana benthamiana. Foliar applications of ET and BR enhanced plant resistance to Pst DC3000 inoculation, while treatment with brassinazole (BRZ, a specific BR biosynthesis inhibitor) eliminated the ET induced plant resistance to Pst DC3000. Silencing of DWARF 4(DWF4, a key BR biosynthetic gene), BRASSINOSTEROID INSENSITIVE 1 (BRI1, aBR receptor) and BRASSINOSTEROID-SIGNALING KINASE 1 (BSK1, downstream of BRI1) also neutralised the ET-induced plant resistance to Pst DC3000. ET can induce callose deposition and reactive oxygen species (ROS) accumulation to resistPst DC3000, BRZ-treated and gene-silenced were completely eliminate this response. Our results suggest BR is involved in ET-induced plant resistance, the involvement of ET in plant resistance is possibly by the induction of callose deposition and ROS accumulation, in a BR-dependent manner.
PMID: 31758615
Physiol Mol Biol Plants , IF:2.005 , 2020 Mar , V26 (3) : P501-511 doi: 10.1007/s12298-020-00765-7
Brassinosteroid seed priming with nitrogen supplementation improves salt tolerance in soybean.
1Biology Department, Faculty of Science, Taibah University, Yanbu, Saudi Arabia.grid.412892.40000 0004 1754 9358; 2Botany and Microbiology Department, Faculty of Science, Cairo University, Giza, Egypt.grid.7776.10000 0004 0639 9286; 3Botany Department, Faculty of Science, Suez Canal University, Ismailia, Egypt.grid.33003.330000 0000 9889 5690; 4Biology Department, Science College, Jouf University, Sakaka, Saudi Arabia.grid.440748.b0000 0004 1756 6705; 5Department of Crop Sciences, College of Agricultural and Marine Sciences, Sultan Qaboos University, Al-Khoud, Oman.grid.412846.d0000 0001 0726 9430; 6Department of Agronomy, University of Agriculture, Faisalabad, 38040 Pakistan.grid.413016.10000 0004 0607 1563
This study was conducted to evaluate the influence of brassinosteroid (24-epibrassinolide, EBL) seed priming and optimal nitrogen (N) supply in improving salt tolerance in soybean. The experimental treatments were (a) control (nutrient solution without N and without EBL priming), (b) nutrient solution without N and EBL seed priming, (c) N supplemented nutrient solution without EBL priming and (d) EBL seed priming + N supplemented nutrient solution under optimal (0 mM NaCl) and salt stress (0 mM NaCl) conditions. Salt stress caused significant reduction in growth and biomass accumulation of soybean. However, EBL seed priming and application of N improved the soybean performance under optimal and salt stress conditions. In this regard, treatments receiving both EBL and N were more effective. EBL priming and N, alone and in combination, triggered the accumulation of osmolytes including proline, glycine betaine and sugars resulting in better photo-protection through maintenance of tissue water content. Antioxidant activity and osmolyte accumulation significantly increased due to combined treatment of N and EBL under normal as well as salt stress conditions. In conclusion, salt stress caused reduction in growth and biomass soybean due to oxidative damage and osmotic stresses. However, soybean performance was improved by seed priming with EBL. Supplementation of N further improved the effectiveness of EBL treatment in improving salt tolerance in soybean.
PMID: 32205926
Genes Genomics , IF:1.188 , 2020 Mar , V42 (3) : P347-354 doi: 10.1007/s13258-019-00909-4
14-3-3 proteins contribute to leaf and root development via brassinosteroid insensitive 1 in Arabidopsis thaliana.
Smart Farm Research Center, Korea Institute of Science and Technology, Gangneung, Gangwon-do, 25451, Republic of Korea.; Department of Biological Sciences, College of Biological Sciences and Biotechnology, Chungnam National University, Daejeon, 34134, Republic of Korea.; Department of Horticulture, College of Agriculture and Life Science, Chungnam National University, Daejeon, 34134, Republic of Korea.; Department of Biological Sciences, College of Biological Sciences and Biotechnology, Chungnam National University, Daejeon, 34134, Republic of Korea. manhooh@cnu.ac.kr.
BACKGROUND: Brassinosteroids (BR) are essential growth hormone in plants. Various components involved in signal transduction pathway have been identified as targets of 14-3-3 phospho-binding proteins. Previously, we showed that 14-3-3 proteins directly interact with the Brassinosteroid Insensitive 1 (BRI1), the BR receptor kinase, and are also subject to phosphorylation in a BR-dependent manner. OBJECTIVE: In this study, we aimed to examine a potential interplay between 14-3-3 proteins and BRI1 in plant growth. METHODS: Morphological phenotypes of a T-DNA insertion mutant line, 14-3-3psiphiepsilon, defective in three 14-3-3 isoforms, psi, phi and epsilon, were characterized and compared with bri1-5 and two transgenic lines for BRI1, BRI1-Flag and BRI1-Flag (14-3-3psiphiepsilon). We also generated complementation lines carrying each of the three 14-3-3 genes and determined their differences in rosette growth. RESULTS: No significant differences between the wild-type and 14-3-3psiphiepsilon seedlings were observed regardless of BR applications. However, BRI1-Flag (14-3-3psiphiepsilon) showed a significantly reduced cold tolerance and BR sensitivity in hypocotyl and root development when compared to BRI1-Flag. In addition, narrower leaf shape and smaller rosette size were observed in BRI1-Flag (14-3-3psiphiepsilon), while the mutant phenotypes were partially restored in the complementation lines, two of which with 14-3-3phi and 14-3-3epsilon showed the rosette growth comparable to BRI1-Flag. CONCLUSION: Taken together, our results suggested that 14-3-3 proteins might positively regulate BRI1 activity and showed that 14-3-3 isoforms have different functional impacts in BR signaling.
PMID: 31902106