Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 9.683
Filtrar
1.
Biochemistry ; 61(22): 2621-2627, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36322126

RESUMO

Photosynthetic reaction centers from a green sulfur bacterium (GsbRC), the PscA/PscA proteins, and photosystem I (PSI), PsaA/PsaB proteins, share structural similarities. Here, we report the redox potential (Em) values of GsbRC by solving the linear Poisson-Boltzmann equation and considering the protonation states of all titratable sites in the entire GsbRC protein and identify the factors that shift the Em values with respect to PSI. The Em values for one-electron reduction of the accessory (A-1) and adjacent (A0) chlorophylls in GsbRC are 100-250 mV higher than those in PSI, whereas the Em values for the Fe4S4 cluster (FX) are at the same level. The PsaA-Trp697/PsaB-Trp677 pair in PSI, which forms the A1-quinone binding site, is replaced with PscA-Arg638 in GsbRC. PsaB-Asp575 in PSI, which is responsible for the Em difference between A1A and A1B quinones in PSI, is absent in GsbRC. These discrepancies also contribute to the upshift in Em(A-1) and Em(A0) in GsbRC with respect to PSI. It seems likely that the upshifted Em for chlorophylls in GsbRC ultimately originates from the characteristics of the electrostatic environment that corresponds to the A1 site of PSI.


Assuntos
Elétrons , Complexo de Proteína do Fotossistema I , Transporte de Elétrons , Complexo de Proteína do Fotossistema I/metabolismo , Clorofila/metabolismo , Sítios de Ligação , Quinonas/química
2.
BMC Plant Biol ; 22(1): 533, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36380296

RESUMO

BACKGROUND: 2-methyl-4-chlorophenoxy acetic acid-Na (MPCA-Na) is a phenoxy carboxylic acid selective hormone herbicide that is widely used in the crop fields. However, drift of MPCA-Na during application is highly damaging to cotton (Gossypium hirsutum) and other crop plants. This study was carried out from 2019 to 2020 to determine the effects of different concentrations of MPCA-Na on physiological and metabolic activities besides growth and yield of cotton plants at seedling, budding, flowering and boll stages. Moreover, we evaluated the different combinations of 24-epibrassinolide, gibberellin (GA3), phthalanilic acid and seaweed fertilizer to ameliorate herbicide damage. RESULTS: 2-methyl-4-chlorophenoxy acetic acid-Na (MPCA-Na) exposure caused a decrease in the chlorophyll content, and an increase in the soluble protein content, Malondialdehyde (MDA) content and protective enzyme activity. It also caused significant reductions in plant height, boll number and the single boll weight at the seedling and budding stages, but had little effects on plant height and the single boll weight at flowering and boll stage. Under the maximum recommended dose of MPCA-Na (130 g/L), the number of cotton bolls at seedling and budding stages decreased by 75.33 and 79.50%, respectively, and the single boll weight decreased by 46.42 and 36.31%, respectively. Nevertheless, the number of G. hirsutum bolls and single boll weight at flowering and boll stage decreased by 48.15 and 5.38%, respectively. Application of plant growth regulators decreased the MDA content, and increased chlorophyll, soluble protein content and protective enzyme activity, and alleviated MCPA-Na toxicity. Positive effects in case of growth regulators treated plants were also observed in terms of G. hirsutum yield. Phthalanilic acid + seaweed fertilizer, 24-epibrassinolide + seaweed fertilizer, and GA3 + seaweed fertilizer should be used at the seedling, budding, and flowering and boll stages, respectively. CONCLUSIONS: The results of current study suggest that certain plant growth regulators could be used to alleviate MPCA-Na damage and maintain G. hirsutum yield. When the cotton exposed to MCPA-Na at the seedling stage, it should be treated with phthalanilic acid + seaweed fertilizer, while plants exposed at the budding stage should be treated with 24-epibrassinolide + seaweed fertilizer, and those exposed at the flowering and boll stages should be treated with GA3 + seaweed fertilizer to mitigate stress.


Assuntos
Ácido 2-Metil-4-clorofenoxiacético , Herbicidas , Gossypium/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Fertilizantes , Clorofila/metabolismo
3.
BMC Plant Biol ; 22(1): 528, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36376811

RESUMO

BACKGROUND: Soil salinization and alkalization are widespread environmental problems that limit grapevine (Vitis vinifera L.) growth and yield. However, little is known about the response of grapevine to alkali stress. This study investigated the differences in physiological characteristics, chloroplast structure, transcriptome, and metabolome in grapevine plants under salt stress and alkali stress. RESULTS: We found that grapevine plants under salt stress and alkali stress showed leaf chlorosis, a decline in photosynthetic capacity, a decrease in chlorophyll content and Rubisco activity, an imbalance of Na+ and K+, and damaged chloroplast ultrastructure. Fv/Fm decreased under salt stress and alkali stress. NPQ increased under salt stress whereas decreased under alkali stress. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment showed the differentially expressed genes (DEGs) induced by salt stress and alkali stress were involved in different biological processes and have varied molecular functions. The expression of stress genes involved in the ABA and MAPK signaling pathways was markedly altered by salt stress and alkali stress. The genes encoding ion transporter (AKT1, HKT1, NHX1, NHX2, TPC1A, TPC1B) were up-regulated under salt stress and alkali stress. Down-regulation in the expression of numerous genes in the 'Porphyrin and chlorophyll metabolism', 'Photosynthesis-antenna proteins', and 'Photosynthesis' pathways were observed under alkali stress. Many genes in the 'Carbon fixation in photosynthetic organisms' pathway in salt stress and alkali stress were down-regulated. Metabolome showed that 431 and 378 differentially accumulated metabolites (DAMs) were identified in salt stress and alkali stress, respectively. L-Glutamic acid and 5-Aminolevulinate involved in chlorophyll synthesis decreased under salt stress and alkali stress. The abundance of 19 DAMs under salt stress related to photosynthesis decreased. The abundance of 16 organic acids in salt stress and 22 in alkali stress increased respectively. CONCLUSIONS: Our findings suggested that alkali stress had more adverse effects on grapevine leaves, chloroplast structure, ion balance, and photosynthesis than salt stress. Transcriptional and metabolic profiling showed that there were significant differences in the effects of salt stress and alkali stress on the expression of key genes and the abundance of pivotal metabolites in grapevine plants.


Assuntos
Vitis , Vitis/metabolismo , Regulação da Expressão Gênica de Plantas , Álcalis/metabolismo , Proteínas de Plantas/genética , Perfilação da Expressão Gênica , Estresse Salino/genética , Transcriptoma , Clorofila/metabolismo
4.
Int J Mol Sci ; 23(21)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36362311

RESUMO

To address the low Ca-induced growth inhibition of tomato plants, the mitigation effect of exogenous Si on tomato seedlings under low-Ca stress was investigated using different application methods. We specifically analyzed the effects of root application or foliar spraying of 1 mM Si on growth conditions, leaf photosynthetic properties, stomatal status, chlorophyll content, chlorophyll fluorescence, ATP activity and content, Calvin cycle-related enzymatic activity, and gene expression in tomato seedlings under low vs. adequate calcium conditions. We found that the low-Ca environment significantly affected (reduced) these parameters, resulting in growth limitation. Surprisingly, the application of 1 mM Si significantly increased plant height, stem diameter, and biomass accumulation, protected photosynthetic pigments, improved gas exchange, promoted ATP production, enhanced the activity of Calvin cycle key enzymes and expression of related genes, and ensured efficient photosynthesis to occur in plants under low-Ca conditions. Interestingly, when the same amount of Si was applied, the beneficial effects of Si were more pronounced under low-Ca conditions that under adequate Ca. We speculate that Si might promote the absorption and transport of calcium in plants. The effects of Si also differed depending on the application method; foliar spraying was better in alleviating photosynthetic inhibition in plants under low-Ca stress, whereas root application of Si significantly promoted root growth and development. Enhancing the photosynthetic capacity by foliar Si application is an effective strategy for ameliorating the growth inhibition of plants under low-Ca stress.


Assuntos
Lycopersicon esculentum , Plântula , Plântula/metabolismo , Lycopersicon esculentum/metabolismo , Silício/farmacologia , Silício/metabolismo , Cálcio/metabolismo , Fotossíntese , Clorofila/metabolismo , Folhas de Planta/metabolismo , Trifosfato de Adenosina/metabolismo
5.
ScientificWorldJournal ; 2022: 3693869, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36408194

RESUMO

The size of nanoparticles (NPs) allows them to accumulate in plants, and they affect plant growth by altering the size of leaves and roots and affecting their photosynthetic reactions by altering the composition of proteins in the electron transport chain, chlorophyll biosynthesis, and carbohydrate synthesis reactions. Plants play an important role on Earth as nutrient producers in all trophic food webs by producing oxygen, absorbing carbon dioxide, and synthesizing edible carbohydrates during photosynthesis. In this study, Fe3O4 and ZnO NPs at various concentrations (0, 1, 2, and 4 mg/l) were used to investigate the effect of NPs on plant morphological parameters and photosynthesis intensity, determining the amount of chlorophyll and the absorption of their light spectrum in common wheat (Triticum aestivum L.). Fe3O4 (25 nm, 2 mg/l, and 4 mg/l) and ZnO (32 nm, 4 mg/l) significantly increased the leaf length of common wheat seedlings. However, Fe3O4 NPs (25 nm, 1 mg/l, and 4 mg/l) significantly reduced light absorption at 645 and 663 nm and the content of chlorophyll b, chlorophyll a, and total chlorophyll, but Fe3O4 (25 nm, 2 mg/l) significantly reduced the chlorophyll a content. In addition, ZnO NPs (32 nm, 1 mg/l) significantly increased the chlorophyll b content. This study has made a major contribution to understanding the effect of low concentrations of NPs on plant seedlings. Currently, NPs with high concentrations, starting at 10 mg/l, have been analysed in other studies, but in the environment, NPs enter plants in low concentrations as dust or through water droplets. Therefore, it is important to determine the potential impact of small concentrations of NPs on crops that are important for agriculture.


Assuntos
Nanopartículas , Óxido de Zinco , Triticum/metabolismo , Óxido de Zinco/farmacologia , Clorofila A/metabolismo , Fotossíntese , Clorofila/metabolismo , Plantas , Plântula
6.
Sci Rep ; 12(1): 17720, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36271277

RESUMO

Using organic fertilizer as part of plant nutrition for decreasing using chemical fertilizer and increasing plants' nutritional value is scientists' concern. Treatments were three concentrations of a mixture of 16 different AAs (amino acid) (0, 150 and 300 mg/L), sprayed every 7 days for 2 months on 4 leafy cabbages. Results showed 300 mg/L AAs increased anthocyanin, flavonoids, phenol, protein and proline. The SOD, POX and APX rose upon AAs usage. The application of AA significantly increased the total chlorophyll, proline, carotenoid, anthocyanin, phenol, protein and flavonoids compared to control plants. The levels of glucosinolate were increased especially in the treatment of 300 mg/L of AAs and glucobrassicin and gluconapin, both of these together represent more than 50% of the total glucosinolate contents. The highest levels of phenolic and flavonoids mostly belonged to quercetin and catechin. Total AAs and total non-essential AAs showed the highest amounts in all treatments in leaves. AAs with different concentrations by foliar application in "Ka- scotch" variety were effective in growth, physiological parameters such as plant height and shoot dry weight, while AA changes were effective in most of the biochemical and nutritional traits of "Ka-red" variety. Conclusively, the glucosinolate, phenolic and flavonoid contents and AAs varied between four cabbage cultivars. Exogenous AAs application at 300 mg/L could be recommended for cabbage cultivation to improve growth, biochemical traits, productivity and nutritional value.


Assuntos
Brassica , Catequina , Glucosinolatos/metabolismo , Brassica/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Aminoácidos , Fertilizantes , Antocianinas , Quercetina , Valor Nutritivo , Clorofila/metabolismo , Flavonoides , Fenóis , Carotenoides , Prolina , Superóxido Dismutase
7.
Int J Mol Sci ; 23(19)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36232356

RESUMO

In both animals and higher plants, xanthine dehydrogenase is a highly conserved housekeeping enzyme in purine degradation where it oxidizes hypoxanthine to xanthine and xanthine to uric acid. Previous reports demonstrated that xanthine dehydrogenase played a vital role in N metabolism and stress response. Is xanthine dehydrogenase involved in regulating leaf senescence? A recessive early senescence mutant with excess sugar accumulation, ossac3, was isolated previously by screening the EMS-induced mutant library. Here, we show that xanthine dehydrogenase not only plays a role in N metabolism but also involved in regulating carbon metabolism in rice. Based on map-based cloning, OsSAC3 was identified, which encodes the xanthine dehydrogenase. OsSAC3 was constitutively expressed in all examined tissues and the OsSAC3 protein located in the cytoplasm. Transcriptional analysis revealed purine metabolism, chlorophyll metabolism, photosynthesis, sugar metabolism and redox balance were affected in the ossac3 mutant. Moreover, carbohydrate distribution was changed, leading to the accumulation of sucrose and starch in the leaves containing ossac3 on account of decreased expression of OsSWEET3a, OsSWEET6a and OsSWEET14 and oxidized inactivation of starch degradation enzymes in ossac3. These results indicated that OsSAC3 played a vital role in leaf senescence by regulating carbon metabolism in rice.


Assuntos
Oryza , Carboidratos , Carbono/metabolismo , Clorofila/metabolismo , Regulação da Expressão Gênica de Plantas , Hipoxantinas/metabolismo , Mutação , Oryza/fisiologia , Fenótipo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Amido/metabolismo , Sacarose/metabolismo , Açúcares/metabolismo , Ácido Úrico/metabolismo , Xantina Desidrogenase/genética , Xantina Desidrogenase/metabolismo
8.
Int J Mol Sci ; 23(19)2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36232683

RESUMO

Melatonin (MT) is crucial in plant growth, development, and response to stress. Celery is a vegetable that grows in a cool climate, and a hot climate can deteriorate its growth, yield, and quality. This study investigates the effect of exogenous melatonin on celery physiology. Transcriptional levels were analyzed by spraying celery with exogenous MT before exposing it to high temperatures. The regulatory mechanism of exogenous MT-mediated heat tolerance was examined. The results show that the exogenous MT reduced the thermal damage state of celery seedlings, as well as the malondialdehyde (MDA) content and relative conductivity (REC), increasing the oxidase activity, the osmotic regulatory substances, and chlorophyll, enhancing the leaf transpiration and the light energy utilization efficiency. We examined the mechanism of exogenous MT in mitigating high-temperature damage using the transcriptome sequencing method. A total of 134 genes were expressed differently at high temperature in the celery treated with MT compared with the untreated celery. Functional annotation analysis revealed that the differentially expressed genes were abundant in the "pyruvate metabolism" pathway and the "peroxidase activity" pathway. According to the pathway-based gene expression analysis, exogenous MT can inhibit the upregulation of pyruvate synthesis genes and the downregulation of pyruvate consumption genes, preventing the accumulated pyruvate from rapidly upregulating the expression of peroxidase genes, and thereby enhancing peroxidase activity. RT-qPCR verification showed a rising encoding peroxidase gene expression under MT treatment. The gene expression pattern involved in pyruvate anabolism and metabolism agreed with the abundant transcriptome expression, validating the physiological index results. These results indicate that the application of exogenous MT to celery significantly enhances the ability of plant to remove reactive oxygen species (ROS) in response to heat stress, thereby improving the ability of plant to resist heat stress. The results of this study provide a theoretical basis for the use of MT to alleviate the damage caused by heat stress in plant growth and development.


Assuntos
Apium , Melatonina , Termotolerância , Antioxidantes/farmacologia , Clorofila/metabolismo , Regulação da Expressão Gênica de Plantas , Malondialdeído/metabolismo , Melatonina/farmacologia , Oxirredutases/metabolismo , Peroxidases/metabolismo , Piruvatos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico , Transcriptoma , Verduras/metabolismo
9.
Int J Mol Sci ; 23(19)2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36232971

RESUMO

Heat stress is one of the most common agrometeorological risks in crop production in the middle and lower reaches of the Yangtze River in China. This study aimed to investigate whether glutamic acid (Glu) or poly-γ-glutamic acid (γ-PGA) biostimulants can improve the thermotolerance of a cool-season Chinese cabbage (Brassica rapa L. ssp. pekinensis) crop. Priming with Glu (2.0 mM) or γ-PGA (20 mg·L-1) was conducted at the third leaf stage by applying as daily foliar sprays for 5 days before 5 days of heat stress (45 °C in 16-h light/35 °C in 8-h dark). Coupled with morpho-physiological and biochemical analyses, transcriptomes of Glu or γ-PGA-primed Chinese cabbage under heat stress were examined by RNA-seq analysis. The results showed that the thermotolerance conferred by Glu and γ-PGA priming was associated with the increased parameters of vegetative growth, gas exchange, and chlorophyll fluorescence. Compared with the control, the dry weights of plants treated with Glu and γ-PGA increased by 51.52% and 39.39%, respectively. Glu and γ-PGA application also significantly increased the contents of total chlorophyll by 42.21% and 23.12%, and carotenoid by 32.00% and 24.00%, respectively. In addition, Glu- and γ-PGA-primed plants markedly inhibited the levels of malondialdehyde, electrolyte leakage, and super-oxide anion radical, which was accompanied by enhanced activity levels of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and peroxidase (POD). Enrichment analysis of Kyoto Encyclopedia of Genes and Genomes (KEGG) categories within the differentially expressed genes (DEGs) functional clusters of RNA-seq data indicated that the expression levels of the genes for DNA replication, DNA repair system, linoleic acid metabolism, cysteine and methionine metabolism, glutathione metabolism, purine and pyrimidine metabolism, carotenoid biosynthesis, and plant-pathogen interaction were commonly up-regulated by both Glu and γ-PGA priming. Glu treatment enhanced the expression levels of the genes involved in aliphatic glucosinolate and 2-oxocarboxylic acid, while γ-PGA treatment activated carotenoid cleavage reaction to synthesize abscisic acid. Taken together, both Glu and γ-PGA have great potential for the preadaptation of Chinese cabbage seedlings to heat stress, with Glu being more effective than γ-PGA.


Assuntos
Brassica rapa , Brassica , Ácido Abscísico/metabolismo , Ânions/metabolismo , Ascorbato Peroxidases/metabolismo , Brassica/metabolismo , Brassica rapa/genética , Catalase/metabolismo , Clorofila/metabolismo , Cisteína/metabolismo , Glucosinolatos/metabolismo , Ácido Glutâmico/metabolismo , Glutationa/metabolismo , Ácido Linoleico/metabolismo , Malondialdeído/metabolismo , Metionina/metabolismo , Óxidos/metabolismo , Fotossíntese , Ácido Poliglutâmico/análogos & derivados , Purinas/metabolismo , Pirimidinas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
10.
Int J Mol Sci ; 23(19)2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36233017

RESUMO

Recent studies have confirmed that chlorophyllase (CLH), a long-found chlorophyll (Chl) dephytylation enzyme for initiating Chl catabolism, has no function in leaf senescence-related Chl breakdown. Yet, CLH is considered to be involved in fruit degreening and responds to external and hormonal stimuli. The purpose of this work was to elucidate in detail the biochemical, structural properties, and gene expression of four CLHs from the Solanum lycopersicum genome so as to understand the roles of Solanum lycopersicum chlorophyllases (SlCLHs). SlCLH1/4 were the predominantly expressed CLH genes during leaf and fruit development/ripening stages, and SlCLH1 in mature green fruit was modulated by light. SlCLH1/2/3/4 contained a highly conserved GHSXG lipase motif and a Ser-Asp-His catalytic triad. We identified Ser159, Asp226, and His258 as the essential catalytic triad by site-directed mutagenesis in recombinant SlCLH1. Kinetic analysis of the recombinant enzymes revealed that SlCLH1 had high hydrolysis activities against Chl a, Chl b, and pheophytin a (Phein a), but preferred Chl a and Chl b over Phein a; SlCLH2/3 only showed very low activity to Chl a and Chl b, while SlCLH4 showed no Chl dephytylation activity. The recombinant SlCLH1/2/3 had different pH stability and temperature optimum. Removal of the predicted N-terminal processing peptide caused a partial loss of activity in recombinant SlCLH1/2 but did not compromise SlCLH3 activity. These different characteristics among SlCLHs imply that they may have different physiological functions in tomato.


Assuntos
Lycopersicon esculentum , Hidrolases de Éster Carboxílico , Clorofila/metabolismo , Regulação da Expressão Gênica de Plantas , Cinética , Lipase/metabolismo , Lycopersicon esculentum/metabolismo
11.
J Plant Physiol ; 279: 153822, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36244263

RESUMO

Nitrogen is one of the macroelements required for plant growth and development and the identification of candidate genes involved in nitrogen deficiency stress is of great importance to the sustainable development of agriculture. Here, we found that the color of apple leaves changed from dark green to yellow-green, the malondialdehyde (MDA) content, soluble protein content, and proline content significantly increased, the chlorophyll content significantly decreased in response to nitrate deficiency stress. According to the physiological and biochemical changes of apple leaves during nitrate deficiency stress, nitrogen deficiency stress was divided into two stages: early nitrogen deficiency stage (ES) and late nitrogen deficiency stage (LS). Transcriptome sequencing was performed in these two stress stages. 5773 differential expression genes (DEGs) were identified in the early nitrogen deficiency stress stage and 6130 DEGs were identified in the late nitrogen deficiency stress stage. Functional analysis of these DEGs revealed that a large number of DEGs were enriched in 'porphyrin and chlorophyll metabolic' pathways, the 'photosynthesis' pathway, the 'photosynthesis-antenna protein' pathway, and the 'ABA', 'ETH', and 'JA' signal transduction pathways, and the metabolic networks of these pathways were constructed. In addition, overexpression of MdNAC4 weakened the tolerance of apple calli to nitrogen deficiency stress. Taken together, our results reveal possible pathways for apple adaptation to nitrogen deficiency stress and identify the function of MdNAC4, a key transcription factor regulating nitrogen deficiency stress, which enriches the molecular mechanism of apple adapting to a nitrogen deficiency environment.


Assuntos
Malus , Malus/genética , Malus/metabolismo , Nitrogênio/metabolismo , Regulação da Expressão Gênica de Plantas , Nitratos/metabolismo , Perfilação da Expressão Gênica/métodos , Clorofila/metabolismo , Transcriptoma , Folhas de Planta/genética , Folhas de Planta/metabolismo
12.
Proc Natl Acad Sci U S A ; 119(42): e2208033119, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36215463

RESUMO

The photosystem II core complex (PSII-CC) is the smallest subunit of the oxygenic photosynthetic apparatus that contains core antennas and a reaction center, which together allow for rapid energy transfer and charge separation, ultimately leading to efficient solar energy conversion. However, there is a lack of consensus on the interplay between the energy transfer and charge separation dynamics of the core complex. Here, we report the application of two-dimensional electronic-vibrational (2DEV) spectroscopy to the spinach PSII-CC at 77 K. The simultaneous temporal and spectral resolution afforded by 2DEV spectroscopy facilitates the separation and direct assignment of coexisting dynamical processes. Our results show that the dominant dynamics of the PSII-CC are distinct in different excitation energy regions. By separating the excitation regions, we are able to distinguish the intraprotein dynamics and interprotein energy transfer. Additionally, with the improved resolution, we are able to identify the key pigments involved in the pathways, allowing for a direct connection between dynamical and structural information. Specifically, we show that C505 in CP43 and the peripheral chlorophyll ChlzD1 in the reaction center are most likely responsible for energy transfer from CP43 to the reaction center.


Assuntos
Clorofila , Complexo de Proteína do Fotossistema II , Clorofila/metabolismo , Transferência de Energia , Fotossíntese , Complexo de Proteína do Fotossistema II/metabolismo , Análise Espectral
13.
Sheng Wu Gong Cheng Xue Bao ; 38(10): 3956-3972, 2022 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-36305421

RESUMO

To explore the mechanism of tea albino variation and high theanine formation, 'Fuyun 6' and a new theanine-rich tea cultivar 'Fuhuang 2' were as materials in this study, pigment content, metabolome and transcriptome of the two cultivars were analyzed by ultramicroelectron microscopy, widely targeted metabolomics, targeted metabolomics and transcriptomics. The results showed that five catechins, theobromine, caffeine, and 20 free amino acids, including theanine, glutamine, arginine, etc., were identified by targeted metabolomics. The amino acid content of 'Fuhuang 2' was significantly higher than that of 'Fuyun 6', and the theanine content was as high as 57.37 mg/g in 'Fuhuang 2'. The ultrastructure of leaves showed that the chloroplast cell structure of 'Fuhuang 2' was fuzzy, most of the grana lamellae were arranged in disorder, with large gaps, and the thylakoids were filiform. The determination of pigments showed that compared with 'Fuyun 6', the contents of chlorophyll A and B, carotenoids, flavonoids and other pigments of 'Fuhuang 2' decreased significantly, some important pigment-related-genes, such as chlorophyllase (CLH), 9-cis-epoxycarotenoid dioxygenase (NCED), flavonoid 3ß-hydroxylase (F3H) and flavonoid 3', 5'-hydroxylase (F3'5'H) were significantly changed. Compared with 'Fuyun 6', 'Fuhuang 2' identified 138 significantly changed metabolites (SCMs) and 658 differentially expressed genes (DEGs). KEGG enrichment analysis showed that SCMs and DEGs were significantly enriched in amino acid biosynthesis, glutathione metabolism and TCA cycle. In general, the albino phenotype of 'Fuhuang 2' may be caused by a deficiency in photosynthetic proteins, chlorophyll metabolism genes and chlorophyll content. The accumulation of high theanine in 'Fuhuang 2' may be due to the low nitrogen consumption in yellowed leaves and the lack of carbon skeleton, amino and nitrogen resources are stored more effectively, resulting in the up regulation of metabolites and related gene expression in the amino acid synthesis pathway, theanine has become a significant accumulation of nitrogen-containing compounds in yellowed leaves.


Assuntos
Camellia sinensis , Camellia sinensis/genética , Clorofila A/análise , Clorofila A/metabolismo , Proteínas de Plantas/genética , Folhas de Planta/química , Clorofila/análise , Clorofila/metabolismo , Transcriptoma , Flavonoides/análise , Flavonoides/metabolismo , Aminoácidos/genética , Chá , Oxigenases de Função Mista/metabolismo , Nitrogênio/metabolismo
14.
Artigo em Inglês | MEDLINE | ID: mdl-36231984

RESUMO

Cadmium toxicity is one of the deleterious abiotic factors that reduce wheat production. Two different cultivars (Akbar and Dilkash) were compared for their cadmium (0, 40 and 80 mg/kg) tolerance and responses towards Bacillus subtilis NA2, Aspergillus niger PMI-118 and L-proline. Both microbes were tested for heavy metal tolerance and production of various plant hormones and biological active enzyme characteristics under normal and cadmium stress. A completely randomized design (two cultivars × four treatments × three cadmium levels × three replicates) was adopted using distilled water as a control. The growth promotion potential of these strains under cadmium stress was determined by N-fixation, IAA synthesis, P-solubilization, amylase and proteases production. A pot experiment under controlled conditions was conducted to evaluate the effect of bacteria, fungi, and L-proline under cadmium stress. It was indicated from the result that plant biomass (46.43%), shoot length (22.40%), root length (25.06%), chlorophyll (17.17%), total sugars (27.07%), total proteins (86.01%) and ascorbic acid (83.27%) were improved with inoculation under control and cadmium stress. The accumulation of total flavonoids (48.64%), total phenolics (24.88%), hydrogen peroxide (53.96%) and activities of antioxidant enzymes CAT (26.37%) and APX (43.71%) were reduced in the plants treated with bacteria, fungi and L-proline than those under control. With parallel aids, Bacillus subtilis NA2 showed a higher cadmium tolerance and plant growth stability as compared to Aspergillus niger PMI-118 and L-proline and may be adopted in the future.


Assuntos
Metais Pesados , Poluentes do Solo , Amilases , Antioxidantes/metabolismo , Ácido Ascórbico/farmacologia , Aspergillus niger , Bacillus subtilis , Biodegradação Ambiental , Cádmio/metabolismo , Clorofila/metabolismo , Flavonoides/farmacologia , Peróxido de Hidrogênio/metabolismo , Metais Pesados/metabolismo , Peptídeo Hidrolases/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Plantas/metabolismo , Prolina/metabolismo , Prolina/farmacologia , Poluentes do Solo/análise , Açúcares/metabolismo , Triticum/metabolismo , Água/metabolismo
15.
PLoS One ; 17(10): e0275813, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36206244

RESUMO

The aim of the present study was to explore the effects of abscisic acid (ABA) on growth and selenium (Se) absorption of the medicinal plant, Perilla frutescens. A pot experiment was conducted to evaluate the effects of different ABA concentrations (0, 1, 5, 10 and 20 µmol/L) on the physiological characteristics and Se absorption capacity of P. frutescens. Application of 5, 10 and 20 µmol/L ABA increased the shoot biomass of P. frutescens, and only 5 and 10 µmol/L ABA increased the root biomass. Application of 5, 10, and 20 µmol/L ABA increased the contents of photosynthetic pigments (chlorophyll a, chlorophyll b, total chlorophyll, and carotenoid), superoxide dismutase activity, peroxidase activity, and soluble protein content of P. frutescens, and decreased the malondialdehyde content in P. frutescens. Only 5 and 10 µmol/L ABA used in the present study increased the catalase activity of P. frutescens. For the Se uptake, only 5 µmol/L ABA increased the Se content, Se extraction and Se bioconcentration factor of both roots and shoots. The findings of the present study indicate that 5 and 10 µmol/L ABA promotes the growth of P. frutescens, whereas 5 µmol/L ABA enhances the Se accumulation capacity in P. frutescens.


Assuntos
Perilla frutescens , Plantas Medicinais , Selênio , Ácido Abscísico/metabolismo , Antioxidantes/metabolismo , Catalase/metabolismo , Clorofila/metabolismo , Clorofila A/metabolismo , Malondialdeído/metabolismo , Perilla frutescens/metabolismo , Raízes de Plantas/metabolismo , Plantas Medicinais/metabolismo , Selênio/farmacologia , Superóxido Dismutase/metabolismo
16.
Genes (Basel) ; 13(10)2022 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-36292762

RESUMO

Faba bean (Vicia faba L.), a drought-sensitive crop, is drastically affected by drought stresses compromising its growth and yield. However, wild relatives of faba bean are considered a reservoir of potential genetic resources for tolerance against abiotic stresses. This study was conducted to characterize wild relatives of faba bean for identification of a specific tolerance system required for its improvement against drought stress. The study focused on physiological, biochemical, and anatomical responses of wild Vicia species under drought stress conditions. The experiment was carried out under various levels of drought stress imposed through different field capacities (FC) which included 80% FC ie (well-watered condition), 55% FC (moderate stress), and 30% FC (severe stress). When compared to plants grown in a control environment, drought stress significantly reduced the studied physiological attributes including soluble sugars (21.3% and 15.8%), protein contents (14.7 and 14.6%), and chlorophyll (8.4 and 28.6%) under moderate (55% FC) and severe drought stress (30% FC), respectively. However, proline content increased by 20.5% and 27.6%, peroxidase activity by 48.5% and 57.1%, and superoxide dismutase activity by 72.6% and 64.8% under moderate and severe stress, respectively. The studied anatomical attributes were also affected under drought stress treatments, including diameter of stem xylem vessels (9.1% and 13.7%), leaf lower epidermal thickness (8.05% and 13.34%), and leaf phloem width (5.3% and 10.1%) under moderate and severe stress, respectively. Wild Vicia spp. showed better tolerance to water-deficit conditions as compared to cultivated Vicia L. The observed potential diversity for drought tolerance in wild Vicia spp. may assist in improvement of faba bean and may also help in understanding the mechanisms of adaptations in drought-prone environments.


Assuntos
Vicia faba , Vicia faba/genética , Secas , Clorofila/metabolismo , Prolina/metabolismo , Água/metabolismo , Superóxido Dismutase , Açúcares/metabolismo , Peroxidases/metabolismo
17.
BMC Plant Biol ; 22(1): 502, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36289462

RESUMO

BACKGROUND: Soil salinization has become a global problem restricting the seed yield and quality of crops, including wheat (Triticum aestivum L.). Salinity significantly alters plant morphology and severely disrupts physiological homeostasis. Salt tolerance of wheat has been widely studied whereas core ion transporters responsive to salt stress remain elusive. RESULTS: In this study, the wheat seedlings were subjected to salinity toxicity for morpho-physiological and transcriptomic analysis of wheat salt tolerance. There was a inversely proportional relationship between salt concentrations and morpho-physiological parameters. Under the condition of 100 mM NaCl, the H2O2, O2-, MDA content and membrane permeability were significantly increased whereas the chlorophyll content was markedly decreased. Under salt stress, a larger proportion of Na+ was partitioned in the roots than in the shoots, which had a lower Na+/K+ ratio and proline content. Salt stress also obviously affected the homeostasis of other cations. Genome-wide transcriptomic analysis showed that a total of 2,807 and 5,570 differentially expressed genes (DEGs) were identified in the shoots and roots, respectively. Functionality analysis showed that these DEGs were mainly enriched in the KEGG pathways related to carbon metabolism, phenylalanine, and amino acid biosynthesis, and were primarily enriched in the GO terms involving proline metabolism and redox processes. The Na+ transporter genes were upregulated under salt stress, which repressed the gene expression of the K+ transporters. Salt stress also significantly elevated the expression of the genes involved in osmoregulation substances biosynthesis, and obviously affected the expression profiling of other cation transporters. Co-expression network analysis identified TaNHX6-D5/TaNHX4-B7 and TaP5CS2-B3 potentially as core members regulating wheat salt tolerance. CONCLUSIONS: These results might help us fully understand the morpho-physiological and molecular responses of wheat seedlings to salt stress, and provide elite genetic resources for the genetic modification of wheat salt tolerance.


Assuntos
Plântula , Triticum , Triticum/metabolismo , Plântula/genética , Plântula/metabolismo , Osmorregulação , Peróxido de Hidrogênio/metabolismo , Cloreto de Sódio/metabolismo , Estresse Salino/genética , Salinidade , Sódio/metabolismo , Clorofila/metabolismo , Prolina/metabolismo , Carbono/metabolismo , Nutrientes , Solo , Fenilalanina/metabolismo , Aminoácidos/metabolismo , Estresse Fisiológico/genética
18.
PLoS One ; 17(10): e0275828, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36215314

RESUMO

Soil salinization is one of the current global environmental problems. Current research on crops in saline-alkali land focuses on salt tolerance, but less on its ecological benefits. However, plants and the environment can interact and influence each other, which is the theory used to carry out Nature-based Solutions (NbS). Therefore, the research on crop plants with both ecological and economic benefits is novel and valuable work. Then three widely planted cash crops (Solanum melongena, Momordica charantia, Capsicum annuum) were selected for salt stress treatment (NaCl, 150mmol/L), some physiological indicators (chlorophyll, soluble protein, Proline (Pro), malondialdehyde (MDA)) of plant and the soil properties (electrical conductivity, pH, the soil salt content) were measured. The results showed that the salinity content of the three plant cultivation soils was significantly different (P<0.05) after the salt stress; all three crops had some desalination capacity, but Capsicum annuum had the strongest salt resistance and desalination capacity.


Assuntos
Álcalis , Capsicum , Capsicum/metabolismo , Clorofila/metabolismo , Produtos Agrícolas/metabolismo , Malondialdeído/metabolismo , Prolina/metabolismo , Salinidade , Cloreto de Sódio , Solo/química
19.
Sci Rep ; 12(1): 17033, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36220848

RESUMO

Application of carbon nanomaterials (CNMs) in agricultural production has piqued the interest of researchers. However, despite the enormous importance of CNMs in plant development, little is known about the effects of carbon nanoparticle (CNP) doses on plant physiological responses. Therefore, the aim of the current study was to check the effects of nanostructured carbon derived from oil fly ash (COFA), which was derived for the first time from high-energy ball-milling followed by a sonication process, on Phaseolus vulgaris L. and Cicer arietinum L. plants. We evaluated the plant physiological and biochemical parameters of the COFA-treated seedlings. Two different doses (4 mg L-1 and 8 mg L-1) of COFA and a control were studied. The results indicated that the germination rate (%), shoot length, root length, pod length, leaf area, fresh weight and dry weight were increased with the addition of COFA. Likewise, COFA increased the contents of chlorophyll pigments (Chla, Chlb, carotenoids), proteins, and carbohydrates in both species compared to the control. Finally, these findings showed that a COFA treatment at 4 mg L-1 after ball milled-sonication in water (BMW4) constituted the best dose for growth and physiology. Our findings reveal that the novel strategy of COFA engineering led to a boost in the growth of Phaseolus vulgaris and Cicer arietinum. Our results have high potential for agricultural research and provide an impact on food security.


Assuntos
Cicer , Nanoestruturas , Phaseolus , Carboidratos/farmacologia , Carbono/metabolismo , Carotenoides/metabolismo , Clorofila/metabolismo , Cinza de Carvão/farmacologia , Produtos Agrícolas/metabolismo , Phaseolus/metabolismo , Água/metabolismo
20.
BMC Plant Biol ; 22(1): 498, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36280828

RESUMO

BACKGROUND: Acer rubrum L. (red maple) is a popular tree with attractive colored leaves, strong physiological adaptability, and a high ornamental value. Changes in leaf color can be an adaptive response to changes in environmental factors, and also a stress response to external disturbances. In this study, we evaluated the effect of girdling on the color expression of A. rubrum leaves. We studied the phenotypic characteristics, physiological and biochemical characteristics, and the transcriptomic and metabolomic profiles of leaves on girdled and non-girdled branches of A. rubrum. RESULTS: Phenotypic studies showed that girdling resulted in earlier formation of red leaves, and a more intense red color in the leaves. Compared with the control branches, the girdled branches produced leaves with significantly different color parameters a*. Physiological and biochemical studies showed that girdling of branches resulted in uneven accumulation of chlorophyll, carotenoids, anthocyanins, and other pigments in leaves above the band. In the transcriptomic and metabolomic analyses, 28,432 unigenes including 1095 up-regulated genes and 708 down-regulated genes were identified, and the differentially expressed genes were mapped to various KEGG (kyoto encyclopedia of genes and genomes) pathways. Six genes encoding key transcription factors related to anthocyanin metabolism were among differentially expressed genes between leaves on girdled and non-girdled branches. CONCLUSIONS: Girdling significantly affected the growth and photosynthesis of red maple, and affected the metabolic pathways, biosynthesis of secondary metabolites, and carbon metabolisms in the leaves. This resulted in pigment accumulation in the leaves above the girdling site, leading to marked red color expression in those leaves. A transcriptome analysis revealed six genes encoding anthocyanin-related transcription factors that were up-regulated in the leaves above the girdling site. These transcription factors are known to be involved in the regulation of phenylpropanoid biosynthesis, anthocyanin biosynthesis, and flavonoid biosynthesis. These results suggest that leaf reddening is a complex environmental adaptation strategy to maintain normal metabolism in response to environmental changes. Overall, the results of these comprehensive phenotype, physiological, biochemical, transcriptomic, and metabolomic analyses provide a deeper and more reliable understanding of the coevolution of red maple leaves in response to environmental changes.


Assuntos
Acer , Acer/genética , Acer/metabolismo , Transcriptoma , Antocianinas/metabolismo , Folhas de Planta/metabolismo , Perfilação da Expressão Gênica/métodos , Clorofila/metabolismo , Carotenoides/metabolismo , Fatores de Transcrição/genética , Carbono/metabolismo , Regulação da Expressão Gênica de Plantas , Cor
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...