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1.
Int J Mol Sci ; 22(10)2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-34064584

RESUMO

Liver fibrosis results from many chronic injuries and may often progress to cirrhosis and hepatocellular carcinoma (HCC). In fact, up to 90% of HCC arise in a cirrhotic liver. Conversely, stress is implicated in liver damage, worsening disease outcome. Hence, stress could play a role in disrupting liver homeostasis, a concept that has not been fully explored. Here, in a murine model of TAA-induced liver fibrosis we identified nerve growth factor (NGF) to be a crucial regulator of the stress-induced fibrogenesis signaling pathway as it activates its receptor p75 neurotrophin receptor (p75NTR), increasing liver damage. Additionally, blocking the NGF decreased liver fibrosis whereas treatment with recombinant NGF accelerated the fibrotic process to a similar extent than stress challenge. We further show that the fibrogenesis induced by stress is characterized by specific changes in the hepatoglycocode (increased ß1,6GlcNAc-branched complex N-glycans and decreased core 1 O-glycans expression) which are also observed in patients with advanced fibrosis compared to patients with a low level of fibrosis. Our study facilitates an understanding of stress-induced liver injury and identify NGF signaling pathway in early stages of the disease, which contributes to the established fibrogenesis.


Assuntos
Regulação da Expressão Gênica , Cirrose Hepática/patologia , Fator de Crescimento Neural/metabolismo , Polissacarídeos/metabolismo , Receptores de Fator de Crescimento Neural/metabolismo , Estresse Fisiológico , Tioacetamida/toxicidade , Animais , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator de Crescimento Neural/genética , Receptores de Fator de Crescimento Neural/genética
2.
Int J Mol Sci ; 22(10)2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-34064673

RESUMO

Histone methylation plays an important regulatory role in the drought response of many plants, but its regulatory mechanism in the drought response of the tea plant remains poorly understood. Here, drought stress was shown to induce lower relative water content and significantly downregulate the methylations of histone H3K4 in the tea plant. Based on our previous analysis of the SET Domain Group (SDG) gene family, the full-length coding sequence (CDS) of CsSDG36 was cloned from the tea cultivar 'Fuding Dabaicha'. Bioinformatics analysis showed that the open reading frame (ORF) of the CsSDG36 gene was 3138 bp, encoding 1045 amino acids and containing the conserved structural domains of PWWP, PHD, SET and PostSET. The CsSDG36 protein showed a close relationship to AtATX4 of the TRX subfamily, with a molecular weight of 118,249.89 Da, and a theoretical isoelectric point of 8.87, belonging to a hydrophilic protein without a transmembrane domain, probably located on the nucleus. The expression of CsSDG36 was not detected in the wild type, while it was clearly detected in the over-expression lines of Arabidopsis. Compared with the wild type, the over-expression lines exhibited lower hyperosmotic resistance by accelerating plant water loss, increasing reactive oxygen species (ROS) pressure, and increasing leaf stomatal density. RNA-seq analysis suggested that the CsSDG36 overexpression caused the differential expression of genes related to chromatin assembly, microtubule assembly, and leaf stomatal development pathways. qRT-PCR analysis revealed the significant down-regulation of stomatal development-related genes (BASL, SBT1.2(SDD1), EPF2, TCX3, CHAL, TMM, SPCH, ERL1, and EPFL9) in the overexpression lines. This study provides a novel sight on the function of histone methyltransferase CsSDG36 under drought stress.


Assuntos
Arabidopsis/fisiologia , Histona-Lisina N-Metiltransferase/metabolismo , Pressão Osmótica , Proteínas de Plantas/metabolismo , Estresse Fisiológico , Chá/enzimologia , Regulação da Expressão Gênica de Plantas , Histona-Lisina N-Metiltransferase/genética , Proteínas de Plantas/genética , Chá/química
3.
BMC Genomics ; 22(1): 415, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-34090335

RESUMO

BACKGROUND: Basic helix-loop-helix (bHLH) is a superfamily of transcription factors that is widely found in plants and animals, and is the second largest transcription factor family in eukaryotes after MYB. They have been shown to be important regulatory components in tissue development and many different biological processes. However, no systemic analysis of the bHLH transcription factor family has yet been reported in Sorghum bicolor. RESULTS: We conducted the first genome-wide analysis of the bHLH transcription factor family of Sorghum bicolor and identified 174 SbbHLH genes. Phylogenetic analysis of SbbHLH proteins and 158 Arabidopsis thaliana bHLH proteins was performed to determine their homology. In addition, conserved motifs, gene structure, chromosomal spread, and gene duplication of SbbHLH genes were studied in depth. To further infer the phylogenetic mechanisms in the SbbHLH family, we constructed six comparative syntenic maps of S. bicolor associated with six representative species. Finally, we analyzed the gene-expression response and tissue-development characteristics of 12 typical SbbHLH genes in plants subjected to six different abiotic stresses. Gene expression during flower and fruit development was also examined. CONCLUSIONS: This study is of great significance for functional identification and confirmation of the S. bicolor bHLH superfamily and for our understanding of the bHLH superfamily in higher plants.


Assuntos
Sorghum , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Genoma de Planta , Filogenia , Sorghum/genética , Estresse Fisiológico/genética
4.
Int J Mol Sci ; 22(10)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-34066274

RESUMO

Polyamines are ubiquitous, low-molecular-weight aliphatic compounds, present in living organisms and essential for cell growth and differentiation. Copper amine oxidases (CuAOs) oxidize polyamines to aminoaldehydes releasing ammonium and hydrogen peroxide, which participates in the complex network of reactive oxygen species acting as signaling molecules involved in responses to biotic and abiotic stresses. CuAOs have been identified and characterized in different plant species, but the most extensive study on a CuAO gene family has been carried out in Arabidopsis thaliana. Growing attention has been devoted in the last years to the investigation of the CuAO expression pattern during development and in response to an array of stress and stress-related hormones, events in which recent studies have highlighted CuAOs to play a key role by modulation of a multilevel phenotypic plasticity expression. In this review, the attention will be focused on the involvement of different AtCuAOs in the IAA/JA/ABA signal transduction pathways which mediate stress-induced phenotypic plasticity events.


Assuntos
Adaptação Fisiológica , Amina Oxidase (contendo Cobre)/metabolismo , Regulação da Expressão Gênica de Plantas , Hormônios/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Plantas/enzimologia , Estresse Fisiológico , Plantas/imunologia , Plantas/metabolismo
5.
Int J Mol Sci ; 22(10)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068175

RESUMO

Low phosphorus (P) availability is a major limiting factor for potatoes. P fertilizer is applied to enhance P availability; however, it may become toxic when plants accumulate at high concentrations. Therefore, it is necessary to gain more knowledge of the morphological and biochemical processes associated with P deficiency and toxicity for potatoes, as well as to explore an alternative approach to ameliorate the P deficiency condition. A comprehensive study was conducted (I) to assess plant morphology, mineral allocation, and metabolites of potatoes in response to P deficiency and toxicity; and (II) to evaluate the potency of plant growth-promoting rhizobacteria (PGPR) in improving plant biomass, P uptake, and metabolites at low P levels. The results revealed a reduction in plant height and biomass by 60-80% under P deficiency compared to P optimum. P deficiency and toxicity conditions also altered the mineral concentration and allocation in plants due to nutrient imbalance. The stress induced by both P deficiency and toxicity was evident from an accumulation of proline and total free amino acids in young leaves and roots. Furthermore, root metabolite profiling revealed that P deficiency reduced sugars by 50-80% and organic acids by 20-90%, but increased amino acids by 1.5-14.8 times. However, the effect of P toxicity on metabolic changes in roots was less pronounced. Under P deficiency, PGPR significantly improved the root and shoot biomass, total root length, and root surface area by 32-45%. This finding suggests the potency of PGPR inoculation to increase potato plant tolerance under P deficiency.


Assuntos
Fósforo/metabolismo , Desenvolvimento Vegetal , Rhizobiaceae/fisiologia , Solanum tuberosum/anatomia & histologia , Solanum tuberosum/metabolismo , Estresse Fisiológico , Folhas de Planta/anatomia & histologia , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Solanum tuberosum/crescimento & desenvolvimento , Solanum tuberosum/microbiologia
6.
Int J Mol Sci ; 22(10)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068347

RESUMO

To ensure global food security under the changing climate, there is a strong need for developing 'climate resilient crops' that can thrive and produce better yields under extreme environmental conditions such as drought, salinity, and high temperature. To enhance plant productivity under the adverse conditions, we constitutively overexpressed a bifunctional wax synthase/acyl-CoA:diacylglycerol acyltransferase (WSD1) gene, which plays a critical role in wax ester synthesis in Arabidopsis stem and leaf tissues. The qRT-PCR analysis showed a strong upregulation of WSD1 transcripts by mannitol, NaCl, and abscisic acid (ABA) treatments, particularly in Arabidopsis thaliana shoots. Gas chromatography and electron microscopy analyses of Arabidopsis seedlings overexpressing WSD1 showed higher deposition of epicuticular wax crystals and increased leaf and stem wax loading in WSD1 transgenics compared to wildtype (WT) plants. WSD1 transgenics exhibited enhanced tolerance to ABA, mannitol, drought and salinity, which suggested new physiological roles for WSD1 in stress response aside from its wax synthase activity. Transgenic plants were able to recover from drought and salinity better than the WT plants. Furthermore, transgenics showed reduced cuticular transpirational rates and cuticle permeability, as well as less chlorophyll leaching than the WT. The knowledge from Arabidopsis was translated to the oilseed crop Camelina sativa (L.) Crantz. Similar to Arabidopsis, transgenic Camelina lines overexpressing WSD1 also showed enhanced tolerance to drought stress. Our results clearly show that the manipulation of cuticular waxes will be advantageous for enhancing plant productivity under a changing climate.


Assuntos
Aciltransferases/metabolismo , Arabidopsis/fisiologia , Brassicaceae/fisiologia , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Estresse Fisiológico , Ceras/metabolismo , Acil Coenzima A/metabolismo , Aciltransferases/genética , Ésteres/metabolismo , Pressão Osmótica , Proteínas de Plantas/genética , Ceras/química
7.
Braz J Biol ; 82: e233547, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34105656

RESUMO

Salvia hispanica cultivation is recent in Brazil and occurs in the off-season, when there is lower water availability in the soil. Water deficit is one of the abiotic factors that most limit germination for compromising the sequence of metabolic events that culminate with seedling emergence. Several attenuating substances have been used to mitigate the effects resulting from this stress and give higher tolerance to the species. Thus, the objective of this study was to evaluate the action of different agents as water stress attenuators in the germination and accumulation of organic compounds in S. hispanica seedlings. The treatments consisted of pre-soaking the seeds for 4 hours in salicylic acid (1 mM.L-1), gibberellic acid (0.4 mM.L-1), distilled water and control treatment (without soaking). The seeds were germinated at osmotic potentials of 0.0, -0.1, -0.2, -0.3 and -0.4 MPa, using PEG 6000 as an osmotic agent. The variables germination percentage, germination speed index, shoot and primary root lengths, total dry mass, proline, total soluble sugars and total free amino acids were analyzed. Salicylic acid and gibberellic acid led to the best results among the attenuators tested, increasing germination, length, dry mass and biochemical components of S. hispanica seedlings under water deficit. Therefore, salicylic and gibberellic acids are efficient in mitigating water stress in S. hispanica seeds up to the potential of -0.4 MPa.


Assuntos
Desidratação , Salvia , Brasil , Germinação , Plântula , Sementes , Estresse Fisiológico , Água
8.
BMC Genomics ; 22(1): 443, 2021 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-34120591

RESUMO

BACKGROUND: An evolutionary model using diploid and allotetraploid cotton species identified 80 % of non-coding transcripts in allotetraploid cotton as being uniquely activated in comparison with its diploid ancestors. The function of the lncRNAs activated in allotetraploid cotton remain largely unknown. RESULTS: We employed transcriptome analysis to examine the relationship between the lncRNAs and mRNAs of protein coding genes (PCGs) in cotton leaf tissue under abiotic stresses. LncRNA expression was preferentially associated with that of the flanking PCGs. Selected highly-expressed lncRNA candidates (n = 111) were subjected to a functional screening pilot test in which virus-induced gene silencing was integrated with abiotic stress treatment. From this low-throughput screen, we obtained candidate lncRNAs relating to plant height and tolerance to drought and other abiotic stresses. CONCLUSIONS: Low-throughput screen is an effective method to find functional lncRNA for further study. LncRNAs were more active in abiotic stresses than PCG expression, especially temperature stress. LncRNA XLOC107738 may take a cis-regulatory role in response to environmental stimuli. The degree to which lncRNAs are constitutively expressed may impact expression patterns and functions on the individual gene level rather than in genome-wide aggregate.


Assuntos
Gossypium , RNA Longo não Codificante , Secas , Regulação da Expressão Gênica de Plantas , Gossypium/genética , Filogenia , Proteínas de Plantas/genética , RNA Longo não Codificante/genética , Estresse Fisiológico/genética
9.
Int J Mol Sci ; 22(11)2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34073724

RESUMO

Water deficit adversely affects apple (Malus domestica) productivity on the Loess Plateau. Autophagy plays a key role in plant responses to unfavorable environmental conditions. Previously, we demonstrated that a core apple autophagy-related protein, MdATG8i, was responsive to various stresses at the transcript level. Here, we investigated the function of this gene in the response of apple to severe drought and found that its overexpression (OE) significantly enhanced drought tolerance. Under drought conditions, MdATG8iOE apple plants exhibited less drought-related damage and maintained higher photosynthetic capacities compared with the wild type (WT). The accumulation of ROS (reactive oxygen species) was lower in OE plants under drought stress and was accompanied by higher activities of antioxidant enzymes. Besides, OE plants accumulated lower amounts of insoluble or oxidized proteins but greater amounts of amino acids and flavonoid under severe drought stress, probably due to their enhanced autophagic activities. Particularly, MdATG8iOE plants showed higher root hydraulic conductivity than WT plants did under drought conditions, indicating the enhanced ability of water uptake. In summary, the overexpression of MdATG8i alleviated oxidative damage, modulated amino acid metabolism and flavonoid synthesis, and improved root water uptake, ultimately contributing to enhanced drought tolerance in apple.


Assuntos
Família da Proteína 8 Relacionada à Autofagia/metabolismo , Secas , Malus/metabolismo , Estresse Oxidativo , Estresse Fisiológico , Autofagia , Flavonoides/biossíntese , Regulação da Expressão Gênica de Plantas , Malus/genética , Malus/fisiologia , Plantas Geneticamente Modificadas
10.
Plant Physiol Biochem ; 165: 239-250, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34082330

RESUMO

Melatonin mediates multiple physiological processes in plants and is involved in many reactions related to the protection of plants from abiotic stress. In this paper, the effect of melatonin on the antioxidant capacity of rice under salt stress was studied. Melatonin alleviated the inhibition of salt stress on the growth of rice seedlings, mainly by increasing the dry weight and fresh weight of shoots and roots. Melatonin alleviated the membrane damage caused by salt stress, which was mainly manifested by the decrease of TBARS content and the decrease of leaf and root damage. During the whole salt stress period, rice after melatonin pretreatment showed lower ROS (H2O2, O2•-,OH-) accumulation. In the early stage (1-3 d) of stress, the rice after melatonin pretreatment showed a strong increase in antioxidant enzyme activity, while in the later stage (5,7 d), it showed a strong increase in antioxidant content. During the whole period of salt stress, melatonin had a weak regulatory effect on AsA-GSH cycle. Through the above regulation process, the decreasing effect of melatonin on ROS content of rice under salt stress did not decrease with prolonged stress time in a short time (1-7 d). In conclusion, melatonin improved the antioxidant capacity of rice under continuous salt stress, and rice showed variable antioxidant strategies after melatonin pretreatment.


Assuntos
Melatonina , Oryza , Antioxidantes , Peróxido de Hidrogênio , Melatonina/farmacologia , Estresse Salino , Plântula , Estresse Fisiológico
11.
Int J Mol Sci ; 22(11)2021 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-34072567

RESUMO

In recent years, much progress has been made in elucidating the functional roles of plant glycine-rich RNA-binding proteins (GR-RBPs) during development and stress responses. Canonical GR-RBPs contain an RNA recognition motif (RRM) or a cold-shock domain (CSD) at the N-terminus and a glycine-rich domain at the C-terminus, which have been associated with several different RNA processes, such as alternative splicing, mRNA export and RNA editing. However, many aspects of GR-RBP function, the targeting of their RNAs, interacting proteins and the consequences of the RNA target process are not well understood. Here, we discuss recent findings in the field, newly defined roles for GR-RBPs and the actions of GR-RBPs on target RNA metabolism.


Assuntos
Regulação da Expressão Gênica de Plantas , Desenvolvimento Vegetal/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Estresse Fisiológico , Germinação/genética , Filogenia , Processamento Pós-Transcricional do RNA , Sementes/genética , Sementes/metabolismo
12.
Int J Mol Sci ; 22(11)2021 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-34072612

RESUMO

The BAG proteins are a family of multi-functional co-chaperones. In plants, BAG proteins were found to play roles both in abiotic and biotic stress tolerance. However, the function of Arabidopsis BAG2 remains largely unknown, whereas BAG6 is required for plants' defense to pathogens, although it remains unknown whether BAG6 is involved in plants' tolerance to abiotic stresses. Here, we show that both BAG2 and BAG6 are expressed in various tissues and are upregulated by salt, mannitol, and heat treatments and by stress-related hormones including ABA, ethylene, and SA. Germination of bag2, bag6 and bag2 bag6 seeds is less sensitive to ABA compared to the wild type (WT), whereas BAG2 and BAG6 overexpression lines are hypersensitive to ABA. bag2, bag6, and bag2 bag6 plants show higher survival rates than WT in drought treatment but display lower survival rates in heat-stress treatment. Consistently, these mutants showed differential expression of several stress- and ABA-related genes such as RD29A, RD29B, NCED3 and ABI4 compared to the WT. Furthermore, these mutants exhibit lower levels of ROS after drought and ABA treatment but higher ROS accumulation after heat treatment than the WT. These results suggest that BAG2 and BAG6 are negatively involved in drought stress but play a positive role in heat stress in Arabidopsis.


Assuntos
Adaptação Fisiológica , Proteínas de Arabidopsis/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas Mitocondriais/genética , Chaperonas Moleculares/genética , Proteínas Nucleares/genética , Estresse Fisiológico , Proteínas de Arabidopsis/metabolismo , Secas , Proteínas Mitocondriais/metabolismo , Chaperonas Moleculares/metabolismo , Mutação , Proteínas Nucleares/metabolismo , Desenvolvimento Vegetal/genética , Reguladores de Crescimento de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo
13.
Cells ; 10(5)2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-34064383

RESUMO

Macrophages comprise a phenotypically and functionally diverse group of hematopoietic cells. Versatile macrophage subsets engage to ensure maintenance of tissue integrity. To perform tissue stress surveillance, macrophages express many different stress-sensing receptors, including purinergic P2X and P2Y receptors that respond to extracellular nucleotides and their sugar derivatives. Activation of G protein-coupled P2Y receptors can be both pro- and anti-inflammatory. Current examples include the observation that P2Y14 receptor promotes STAT1-mediated inflammation in pro-inflammatory M1 macrophages as well as the demonstration that P2Y11 receptor suppresses the secretion of tumor necrosis factor (TNF)-α and concomitantly promotes the release of soluble TNF receptors from anti-inflammatory M2 macrophages. Here, we review macrophage regulation by P2Y purinergic receptors, both in physiological and disease-associated inflammation. Therapeutic targeting of anti-inflammatory P2Y receptor signaling is desirable to attenuate excessive inflammation in infectious diseases such as COVID-19. Conversely, anti-inflammatory P2Y receptor signaling must be suppressed during cancer therapy to preserve its efficacy.


Assuntos
Inflamação/imunologia , Macrófagos/imunologia , Receptores Purinérgicos P2Y/metabolismo , Estresse Fisiológico/imunologia , Animais , COVID-19/sangue , COVID-19/tratamento farmacológico , COVID-19/imunologia , Humanos , Vigilância Imunológica/efeitos dos fármacos , Vigilância Imunológica/imunologia , Inflamação/sangue , Inflamação/tratamento farmacológico , Macrófagos/metabolismo , Camundongos , Neoplasias/sangue , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Agonistas do Receptor Purinérgico P2Y/farmacologia , Agonistas do Receptor Purinérgico P2Y/uso terapêutico , Antagonistas do Receptor Purinérgico P2Y/farmacologia , Antagonistas do Receptor Purinérgico P2Y/uso terapêutico , Receptores do Fator de Necrose Tumoral/metabolismo , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Fator de Necrose Tumoral alfa/metabolismo
14.
Biosensors (Basel) ; 11(5)2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-34067188

RESUMO

Emotional stress negatively affects the quality of a person's daily life. From a physiological point of view, stress is expressed in the excitation of the hypothalamic-pituitary-adrenal cortex axis, which leads to the release of the hormone cortisol into the blood. We developed a lateral flow immunoassay to detect cortisol in human salivary fluid and tested it on 10 healthy volunteers daily for about one month (n = 293 saliva samples). Cortisol was detected in concentrations ranging from 1 to 70 ng/mL. Salivary cortisol levels were confirmed by ELISA. The straightness range of LFIA calibration was from 1 to 100 ng/mL. The diagnostic sensitivity of the method was 73%. It was found that in 3 out of 10 subjects, fluctuations in the level of cortisol in saliva partially corresponded to the subjectively assessed level of stress.


Assuntos
Hidrocortisona/metabolismo , Monitorização Fisiológica/métodos , Saliva/metabolismo , Estresse Fisiológico/fisiologia , Humanos , Imunoensaio/métodos
15.
Int J Mol Sci ; 22(10)2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-34070033

RESUMO

Drought response in wheat is considered a highly complex process, since it is a multigenic trait; nevertheless, breeding programs are continuously searching for new wheat varieties with characteristics for drought tolerance. In a previous study, we demonstrated the effectiveness of a mutant known as RYNO3936 that could survive 14 days without water. In this study, we reveal another mutant known as BIG8-1 that can endure severe water deficit stress (21 days without water) with superior drought response characteristics. Phenotypically, the mutant plants had broader leaves, including a densely packed fibrous root architecture that was not visible in the WT parent plants. During mild (day 7) drought stress, the mutant could maintain its relative water content, chlorophyll content, maximum quantum yield of PSII (Fv/Fm) and stomatal conductance, with no phenotypic symptoms such as wilting or senescence despite a decrease in soil moisture content. It was only during moderate (day 14) and severe (day 21) water deficit stress that a decline in those variables was evident. Furthermore, the mutant plants also displayed a unique preservation of metabolic activity, which was confirmed by assessing the accumulation of free amino acids and increase of antioxidative enzymes (peroxidases and glutathione S-transferase). Proteome reshuffling was also observed, allowing slow degradation of essential proteins such as RuBisCO during water deficit stress. The LC-MS/MS data revealed a high abundance of proteins involved in energy and photosynthesis under well-watered conditions, particularly Serpin-Z2A and Z2B, SGT1 and Calnexin-like protein. However, after 21 days of water stress, the mutants expressed ABC transporter permeases and xylanase inhibitor protein, which are involved in the transport of amino acids and protecting cells, respectively. This study characterizes a new mutant BIG8-1 with drought-tolerant characteristics suited for breeding programs.


Assuntos
Secas , Mutação , Triticum/genética , Triticum/fisiologia , Aclimatação/genética , Aminoácidos/metabolismo , Antioxidantes/metabolismo , Clorofila/metabolismo , Metanossulfonato de Etila/toxicidade , Mutagênicos/toxicidade , Fenótipo , Complexo de Proteína do Fotossistema II/metabolismo , Melhoramento Vegetal , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Proteoma/metabolismo , Ribulose-Bifosfato Carboxilase/metabolismo , Estresse Fisiológico/genética , Triticum/efeitos dos fármacos , Água/metabolismo
16.
Int J Mol Sci ; 22(10)2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-34070080

RESUMO

In the last two decades, global environmental change has increased abiotic stress on plants and severely affected crops. For example, drought stress is a serious abiotic stress that rapidly and substantially alters the morphological, physiological, and molecular responses of plants. In Arabidopsis, several drought-responsive genes have been identified; however, the underlying molecular mechanism of drought tolerance in plants remains largely unclear. Here, we report that the "domain of unknown function" novel gene DUF569 (AT1G69890) positively regulates drought stress in Arabidopsis. The Arabidopsis loss-of-function mutant atduf569 showed significant sensitivity to drought stress, i.e., severe wilting at the rosette-leaf stage after water was withheld for 3 days. Importantly, the mutant plant did not recover after rewatering, unlike wild-type (WT) plants. In addition, atduf569 plants showed significantly lower abscisic acid accumulation under optimal and drought-stress conditions, as well as significantly higher electrolyte leakage when compared with WT Col-0 plants. Spectrophotometric analyses also indicated a significantly lower accumulation of polyphenols, flavonoids, carotenoids, and chlorophylls in atduf569 mutant plants. Overall, our results suggest that novel DUF569 is a positive regulator of the response to drought in Arabidopsis.


Assuntos
Aclimatação/genética , Arabidopsis/genética , Secas , Genes de Plantas , Ácido Abscísico/metabolismo , Aclimatação/fisiologia , Antioxidantes/metabolismo , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Técnicas de Inativação de Genes , Peroxidação de Lipídeos , Mutação com Perda de Função , Fenótipo , Plantas Geneticamente Modificadas , Estresse Fisiológico/genética
17.
BMC Plant Biol ; 21(1): 259, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-34090337

RESUMO

BACKGROUND: Nitrogen (N) and phosphorus (P) are macronutrients essential for crop growth and productivity. In cultivated fields, N and P levels are rarely sufficient, contributing to the gap between realized and potential production. Fertilizer application increases nutrient availability, but is not available to all farmers, nor are current rates of application sustainable or environmentally desirable. Transcriptomic studies of cereal crops have revealed dramatic responses to either low N or low P single stress treatments. In the field, however, levels of both N and P may be suboptimal. The interaction between N and P starvation responses remains to be fully characterized. RESULTS: We characterized growth and root and leaf transcriptomes of young maize plants under nutrient replete, low N, low P or combined low NP conditions. We identified 1555 genes to respond to our nutrient treatments, in one or both tissues. A large group of genes, including many classical P starvation response genes, were regulated antagonistically between low N and P conditions. An additional experiment over a range of N availability indicated that a mild reduction in N levels was sufficient to repress the low P induction of P starvation genes. Although expression of P transporter genes was repressed under low N or low NP, we confirmed earlier reports of P hyper accumulation under N limitation. CONCLUSIONS: Transcriptional responses to low N or P were distinct, with few genes responding in a similar way to the two single stress treatments. In combined NP stress, the low N response dominated, and the P starvation response was largely suppressed. A mild reduction in N availability was sufficient to repress the induction of P starvation associated genes. We conclude that activation of the transcriptional response to P starvation in maize is contingent on N availability.


Assuntos
Nitrogênio/farmacologia , Fósforo/farmacologia , Zea mays/efeitos dos fármacos , Zea mays/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Nitrogênio/administração & dosagem , Fósforo/administração & dosagem , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plântula/crescimento & desenvolvimento , Estresse Fisiológico/efeitos dos fármacos , Zea mays/metabolismo
18.
Nat Commun ; 12(1): 3285, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-34078899

RESUMO

In peripheral nerves, Schwann cells form myelin and provide trophic support to axons. We previously showed that the mitochondrial protein prohibitin 2 can localize to the axon-Schwann-cell interface and is required for developmental myelination. Whether the homologous protein prohibitin 1 has a similar role, and whether prohibitins also play important roles in Schwann cell mitochondria is unknown. Here, we show that deletion of prohibitin 1 in Schwann cells minimally perturbs development, but later triggers a severe demyelinating peripheral neuropathy. Moreover, mitochondria are heavily affected by ablation of prohibitin 1 and demyelination occurs preferentially in cells with apparent mitochondrial loss. Furthermore, in response to mitochondrial damage, Schwann cells trigger the integrated stress response, but, contrary to what was previously suggested, this response is not detrimental in this context. These results identify a role for prohibitin 1 in myelin integrity and advance our understanding about the Schwann cell response to mitochondrial damage.


Assuntos
Nervo Femoral/metabolismo , Mitocôndrias/metabolismo , Proteínas Repressoras/genética , Células de Schwann/metabolismo , Nervo Isquiático/metabolismo , Nervo Tibial/metabolismo , Animais , Aspartato-Amônia Ligase/genética , Aspartato-Amônia Ligase/metabolismo , Axônios/metabolismo , Axônios/ultraestrutura , Fator de Iniciação 2 em Eucariotos/genética , Fator de Iniciação 2 em Eucariotos/metabolismo , Feminino , Nervo Femoral/patologia , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mitocôndrias/patologia , Bainha de Mielina/metabolismo , Bainha de Mielina/patologia , Fosfoenolpiruvato Carboxiquinase (ATP)/genética , Fosfoenolpiruvato Carboxiquinase (ATP)/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Repressoras/deficiência , Células de Schwann/patologia , Nervo Isquiático/patologia , Estresse Fisiológico , Nervo Tibial/patologia , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo , Proteína 1 de Ligação a X-Box/genética , Proteína 1 de Ligação a X-Box/metabolismo , gama-Glutamilciclotransferase/genética , gama-Glutamilciclotransferase/metabolismo
19.
Nat Commun ; 12(1): 3282, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-34078900

RESUMO

Bacterial processes necessary for adaption to stressful host environments are potential targets for new antimicrobials. Here, we report large-scale transcriptomic analyses of 32 human bacterial pathogens grown under 11 stress conditions mimicking human host environments. The potential relevance of the in vitro stress conditions and responses is supported by comparisons with available in vivo transcriptomes of clinically important pathogens. Calculation of a probability score enables comparative cross-microbial analyses of the stress responses, revealing common and unique regulatory responses to different stresses, as well as overlapping processes participating in different stress responses. We identify conserved and species-specific 'universal stress responders', that is, genes showing altered expression in multiple stress conditions. Non-coding RNAs are involved in a substantial proportion of the responses. The data are collected in a freely available, interactive online resource (PATHOgenex).


Assuntos
Regulação Bacteriana da Expressão Gênica , Bactérias Gram-Negativas/genética , Bactérias Gram-Positivas/genética , RNA Bacteriano/genética , Estresse Fisiológico/genética , Transcriptoma , Adaptação Fisiológica/genética , Atlas como Assunto , Bases de Dados Genéticas , Perfilação da Expressão Gênica , Genes Bacterianos , Bactérias Gram-Negativas/classificação , Bactérias Gram-Negativas/metabolismo , Bactérias Gram-Negativas/patogenicidade , Bactérias Gram-Positivas/classificação , Bactérias Gram-Positivas/metabolismo , Bactérias Gram-Positivas/patogenicidade , Interações entre Hospedeiro e Microrganismos/genética , Humanos , Internet , Microbiota/genética , Filogenia , RNA Bacteriano/metabolismo
20.
Nat Commun ; 12(1): 3457, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103505

RESUMO

Bacillus subtilis is a soil bacterium that is competent for natural transformation. Genetically distinct B. subtilis swarms form a boundary upon encounter, resulting in killing of one of the strains. This process is mediated by a fast-evolving kin discrimination (KD) system consisting of cellular attack and defence mechanisms. Here, we show that these swarm antagonisms promote transformation-mediated horizontal gene transfer between strains of low relatedness. Gene transfer between interacting non-kin strains is largely unidirectional, from killed cells of the donor strain to surviving cells of the recipient strain. It is associated with activation of a stress response mediated by sigma factor SigW in the donor cells, and induction of competence in the recipient strain. More closely related strains, which in theory would experience more efficient recombination due to increased sequence homology, do not upregulate transformation upon encounter. This result indicates that social interactions can override mechanistic barriers to horizontal gene transfer. We hypothesize that KD-mediated competence in response to the encounter of distinct neighbouring strains could maximize the probability of efficient incorporation of novel alleles and genes that have proved to function in a genomically and ecologically similar context.


Assuntos
Bacillus subtilis/genética , Transferência Genética Horizontal , Adaptação Fisiológica , Membrana Celular/metabolismo , DNA Bacteriano/genética , Genoma Bacteriano , Mutação/genética , Nucleotídeos/genética , Recombinação Genética/genética , Estresse Fisiológico , Transformação Genética , Regulação para Cima
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