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1.
Bol. latinoam. Caribe plantas med. aromát ; 18(5): 444-458, sept. 2019. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1008263

RESUMO

This review work focuses on how the secondary chemistry could help in the survival of plants in high mountain habitats under extreme environmental conditions. The elevated levels of stress in high areas of the tropic and subtropic change dramatically not only by following the annual cycles of winter and summer but they also change in a single day. Some species, however, are able to successfully grow at heights more than 3000 m in the tropical mountains due, in part, to highly specialized physiological processes that affect their physical and chemical responses. In this study, it describes some strategies of how the secondary metabolites could help the plants to stand the high levels of stress in the high mountain ecosystems.


Este trabajo de revisión se centra en cómo la química secundaria podría ayudar en la supervivencia de plantas en hábitats de alta montaña en condiciones ambientales extremas. Los altos niveles de estrés en las zonas altas del trópico y subtrópico cambian dramáticamente no solo al seguir los ciclos anuales de invierno y verano, sino que también cambian en un solo día. Sin embargo, algunas especies pueden crecer con éxito a alturas superiores a 3000 m en las montañas tropicales debido, en parte, a procesos fisiológicos altamente especializados que afectan sus respuestas físicas y químicas. En esta revisión, se describen algunas estrategias de cómo los metabolitos secundarios podrían ayudan a las plantas a soportar los altos niveles de estrés en los ecosistemas de alta montaña.


Assuntos
Plantas/química , Estresse Fisiológico , Óleos Voláteis/química , Altitude , Floroglucinol/análise , Floroglucinol/química , Terpenos/análise , Terpenos/química , Flavonoides/análise , Flavonoides/química
2.
J Cancer Res Clin Oncol ; 145(10): 2433-2444, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31485767

RESUMO

PURPOSE: The clinical importance of cancer stem cells (CSCs) in head and neck squamous cell carcinoma (HNSCC) is well recognized. However, a reliable method for the detection of functioning CSC has not yet been established. We hypothesized that YAP1, a transcriptional coactivator, and SOX2, a master transcription factor of SCC, may cooperatively induce stemness through transcriptional reprogramming. METHODS: We immunohistochemically examined the expression of SOX2 and YAP1 in the CD44 variant 9 (CD44v9)-positive invasion front. A CSC-inducible module was identified through a combination of siRNAs and sphere formation assays. YAP1 and SOX2 interactions were analyzed in vitro. RESULTS: The triple overexpression of SOX2, YAP1, and CD44v9 was significantly associated with poor prognosis. TCGA data revealed that the CSC-inducible module, which was related to EMT and angiogenesis, was significantly correlated with poor prognosis. The KLF7 expression, representatively chosen from the module, also correlated with poor prognosis and was essential for sphere formation and CSC propagation. Sphere stress-activated YAP1 enhanced SOX2 activity. CONCLUSIONS: The stress-triggered activation of YAP1/SOX2 transcriptionally reprograms HNSCC for the acquisition of stemness. Triple SOX2, YAP1, and CD44v9 immunostaining assays may be useful for the selection of high-risk patients with functioning CSCs, and YAP1 targeting may lead to the development of a CSC-targeting therapy.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Células-Tronco Neoplásicas/metabolismo , Fosfoproteínas/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Estresse Fisiológico , Ativação Transcricional , Biomarcadores , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Células-Tronco Neoplásicas/patologia , RNA Interferente Pequeno/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Estresse Fisiológico/genética
3.
Ying Yong Sheng Tai Xue Bao ; 30(9): 3155-3163, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31529891

RESUMO

The effects of drought stress on root morphology, endogenous hormones, chlorophyll fluorescence and active oxygen metabolism in three different stages of sweet potato rooting, branching and tubering stage were studied by sand culture method with 10% PEG-6000 simulating drought stress. The results showed that the biomass of sweet potato decreased significantly under drought stress in different periods, with the degree of drought stress being 10 days > 20 days > 30 days after transplantation. Drought stress significantly reduced the average diameter and root volume at the 10 days after transplantation, followed by the 20 days and 30 days. Both the main and interactive effects of different periods and drought stress significantly affected root morphological characteristics. Drought stress at different stages significantly reduced chlorophyll fluorescence characteristics, resulting in blocked photosynthate formation, and inhibited root differentiation. Drought stress affected the proportion of endogenous hormones in root (with decreases of indoleacetic acid and zeatin riboside contents but increases of abscisic acid contents) and thus inhibiting root differentiation of sweet potato. The earlier the stress time, the more serious the root differentiation of sweet potato was hindered. Across different drought-tolerant varieties, the severity of root differentiation blocked in Jishu 26 was significantly lower than that in Guangshu 87. Root endogenous hormones and chlorophyll fluorescence were the key drivers for the average diameter and root volume (R1=0.936, R2=0.972). Zeatin riboside, maximal photochemical efficiency, and abscisic acid had greater direct effects on average diameter and root volume of sweet potato. Sweet potato was more sensitive to drought stress in the 10th day after transplanting. Therefore, proper irrigation should be considered in case of drought in seedling stage of sweet potato.


Assuntos
Secas , Ipomoea batatas/fisiologia , Ácido Abscísico , Biomassa , Plântula , Estresse Fisiológico
4.
Sheng Wu Gong Cheng Xue Bao ; 35(9): 1676-1685, 2019 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-31559749

RESUMO

Drought stress affects the growth and development of rice, resulting in severe loss in yield and quality. Ectopic expression of the bacterial RNA chaperone, cold shock protein (Csp), can improve rice drought tolerance. Archaeal TRAM (TRM2 and MiaB) proteins have similar structure and biochemical functions as bacterial Csp. Moreover, DNA replication, transcription and translation of archaea are more similar to those in eukaryotes. To test if archaeal RNA chaperones could confer plant drought tolerance, we selected two TRAM proteins, Mpsy_3066 and Mpsy_0643, from a cold-adaptive methanogenic archaea Methanolobus psychrophilus R15 to study. We overexpressed the TRAM proteins in rice and performed drought treatment at seedling and adult stage. The results showed that overexpression both TRAM proteins could significantly improve the tolerance of rice to drought stress. We further demonstrated in rice protoplasts that the TRAMs could abolish misfolded RNA secondary structure and improve translation efficiency, which might explain how TRAMs improve drought tolerance transgenic rice. Our work supports that ectopic expression of archaeal TRAMs effectively improve drought tolerance in rice.


Assuntos
Oryza , Secas , Expressão Ectópica do Gene , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Plantas Geneticamente Modificadas , Estresse Fisiológico
5.
Oecologia ; 191(2): 311-323, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31535254

RESUMO

Extensive research confirms that environmental stressors like predation risk can profoundly affect animal condition and physiology. However, there is a lack of experimental research assessing the suite of physiological responses to risk that may arise under realistic field conditions, leaving a fragmented picture of risk-related physiological change and potential downstream consequences on individuals. We increased predation risk in free-ranging snowshoe hares (Lepus americanus) during two consecutive summers by simulating natural chases using a model predator and monitored hares intensively via radio-telemetry and physiological assays, including measures designed to assess changes in stress physiology and overall condition. Compared to controls, risk-augmented hares had 25.8% higher free plasma cortisol, 15.9% lower cortisol-binding capacity, a greater neutrophil:lymphocyte skew, and a 10.4% increase in glucose. Despite these changes, intra-annual changes in two distinct condition indices, were unaffected by risk exposure. We infer risk-augmented hares compensated for changes in their stress physiology through either compensatory foraging and/or metabolic changes, which allowed them to have comparable condition to controls. Although differences between controls and risk-augmented hares were consistent each year, both groups had heightened stress measures during the second summer, likely reflecting an increase in natural stressors (i.e., predators) in the environment. We show that increased predation risk in free-ranging animals can profoundly alter stress physiology and that compensatory responses may contribute to limiting effects of such changes on condition. Ultimately, our results also highlight the importance of biologically relevant experimental risk manipulations in the wild as a means of assessing physiological responses to natural stressors.


Assuntos
Lebres , Animais , Hidrocortisona , Comportamento Predatório , Estações do Ano , Estresse Fisiológico
6.
Adv Exp Med Biol ; 1200: 91-162, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31471796

RESUMO

To reverse the trend of declining wildlife populations globally, individuals must be provided with conditions that allow them to not just survive, but to thrive. It is no longer only the remit of captive breeding programs to ensure animal well-being; in situ conservation efforts also must consider how environmental and anthropogenic pressures impact wild populations, and how to mitigate them-especially with regards to reproduction and survival. Stress and welfare are complex concepts that necessitate an understanding of how stressors affect animals on both individual and population levels. There are species differences in how factors impact well-being, related in part to natural history, which also are shaped by individual perceptions and coping abilities. A multitude of stress-related responses then have the potential to disrupt fertility on many levels, and ultimately fitness. A major limitation to advancing welfare science is the lack of definitive tests to verify welfare status; i.e., is the animal happy or not? While analyses of circulating or excreted glucocorticoids have for decades been the primary method of assessing stress, today we recognize the need for more objective indicators that incorporate multiple physiological systems, including behavior, to assess both negative and positive welfare states. In this chapter, we discuss the potential for stress to disrupt, and sometimes facilitate reproduction, including the key role that glucocorticoids play. We then discuss a number of physiological biomarkers, which in addition to glucocorticoids, have the potential to assess well-being and the role of stress on reproduction. Finally, we discuss allostatic load, a method by which multiple physiological markers are used to inform on morbidity and mortality risk in humans, which if applied to wildlife, could be a powerful tool for conservation.


Assuntos
Alostase , Animais Selvagens , Glucocorticoides/fisiologia , Reprodução , Estresse Fisiológico , Animais , Biomarcadores , Conservação dos Recursos Naturais
7.
Nan Fang Yi Ke Da Xue Xue Bao ; 39(8): 993-997, 2019 Aug 30.
Artigo em Chinês | MEDLINE | ID: mdl-31511222

RESUMO

OBJECTIVE: To investigate the role of lumbar facet joint degeneration in the development of degenerative lumbar scoliosis caused by asymmetric stress. METHODS: Thirty-six New Zealand white rabbits were randomly divided into 3 groups (n=12): Group A with aspiration of the nucleus pulposus to induce disc degeneration; Group B with removal of the left capsule from the facet joints at L3/4 to L5/6 to induce degeneration; and Group C with both treatments. Springs were deployed on the left adjacent facets at L3/4, L5/6 and L5/6 to stress the facet joints. Serial radiographs were taken at 3 and 6 months, and the facet joint tissues were sampled at 6 months for Safranin O-fast green staining to assess the severity of cartilage degeneration based on the Mankin score. RESULTS: The Cobb angle differed significantly among the 3 groups (F=24.865, P=0.000). In all the groups, the Cobb angles at 6 months increased significantly as compared with that at 3 months (P <0.05). The Cobb angles were significantly greater in group C than in the other 2 groups at both 3 and 6 months (P <0.05) but showed no significant difference between Groups A and B (P>0.05). The severity of facet joint degeneration also differed significantly among the 3 groups (F= 22.009, P=0.000), and was the most severe in group C (P <0.05); facet joint degeneration was more severe in group B than in group A (P <0.05). CONCLUSIONS: Facet joint degeneration is an important factor that contributes to the development of degenerative lumbar scoliosis. Disc degeneration and facet joints degeneration can lead to lumbar scoliosis, which in turn aggravates disc degeneration, facet joints degeneration and asymmetric stress, thus forming a vicious circle to further exacerbate lumbar scoliosis.


Assuntos
Degeneração do Disco Intervertebral , Escoliose , Articulação Zigapofisária , Animais , Vértebras Lombares , Região Lombossacral , Coelhos , Estresse Fisiológico
8.
J Agric Food Chem ; 67(32): 8905-8918, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31380641

RESUMO

NAC TFs play crucial roles in response to abiotic stresses in plants. Here, ZmNAC071 was identified as a nuclear located transcriptional repressor. Overexpression of ZmNAC071 in Arabidopsis enhanced sensitivity of transgenic plants to ABA and osmotic stress. The expression levels of SODs, PODs, P5CSs, and AtMYB61 were inhibited by ZmNAC071, which results in reduced ROS scavenging and proline content, increased ROS level, and water loss. Besides, the expression levels of some ABA or abiotic stress-related genes, like ABIs, RD29A, DREBs, and LEAs were also significantly inhibited by ZmNAC071. Yeast one-hybrid assay demonstrated that ZmNAC071 specifically bound to the cis-acting elements containing CGT[G/A] core sequences in the promoter of stress-related genes, suggesting that ZmNAC071 may participate in the regulation of transcription of these genes through recognizing the core sequences CGT[G/A]. These results will facilitate further studies concerning the cis-elements and downstream genes targeted by ZmNAC071 in maize.


Assuntos
Arabidopsis/efeitos dos fármacos , Arabidopsis/fisiologia , Ácido Ascórbico/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/fisiologia , Fatores de Transcrição/genética , Zea mays/genética , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação para Baixo/efeitos dos fármacos , Pressão Osmótica , Plantas Geneticamente Modificadas/genética , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico , Fatores de Transcrição/metabolismo
9.
Gene ; 717: 144043, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31400407

RESUMO

Genes involved in the repair of DNA damage are emerging as playing important roles during the disease processes caused by pathogenic fungi. However, there are potentially hundreds of genes involved in DNA repair in a fungus and some of those genes can play additional roles within the cell. One such gene is RAD23, required for virulence of the human pathogenic fungus Cryptococcus neoformans, that encodes a protein involved in the nucleotide excision repair (NER) pathway. However, Rad23 is a dual function protein, with a role in either repair of damaged DNA or protein turn over by directing proteins to the proteasome. Here, these two functions of Rad23 were tested by the creation of a series of domain deletion alleles of RAD23 and the assessment of the strains for DNA repair, proteasome functions, and virulence properties. Deletion of the different domains was able to uncouple the two functions of Rad23, and the phenotypes of strains carrying such forms indicated that the role of RAD23 in virulence is due to its function in proteasomal-mediated protein degradation rather than NER.


Assuntos
Cryptococcus neoformans/genética , Cryptococcus neoformans/patogenicidade , Reparo do DNA/fisiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Animais , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Larva/microbiologia , Mariposas/microbiologia , Mutação , Complexo de Endopeptidases do Proteassoma/metabolismo , Domínios Proteicos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Estresse Fisiológico/genética , Virulência
10.
BMC Plant Biol ; 19(1): 341, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31382871

RESUMO

BACKGROUND: Barley is a low phosphorus (P) demand cereal crop. Tibetan wild barley, as a progenitor of cultivated barley, has revealed outstanding ability of tolerance to low-P stress. However, the underlying mechanisms of low-P adaption and the relevant genetic controlling are still unclear. RESULTS: We identified low-P tolerant barley lines in a doubled-haploid (DH) population derived from an elite Tibetan wild barley accession and a high-yield cultivar. The tolerant lines revealed greater root plasticity in the terms of lateral root length, compared to low-P sensitive lines, in response to low-P stress. By integrating the QTLs associated with root length and root transcriptomic profiling, candidate genes encoding isoflavone reductase, nitrate reductase, nitrate transporter and transcriptional factor MYB were identified. The differentially expressed genes (DEGs) involved the growth of lateral root, Pi transport within cells as well as from roots to shoots contributed to the differences between low-P tolerant line L138 and low-P sensitive lines L73 in their ability of P acquisition and utilization. CONCLUSIONS: The plasticity of root system is an important trait for barley to tolerate low-P stress. The low-P tolerance in the elite DH line derived from a cross of Tibetan wild barley and cultivated barley is characterized by enhanced growth of lateral root and Pi recycling within plants under low-P stress.


Assuntos
Hordeum/fisiologia , Fósforo/metabolismo , Raízes de Plantas/fisiologia , Adaptação Fisiológica , Perfilação da Expressão Gênica , Genes de Plantas/genética , Genes de Plantas/fisiologia , Hordeum/genética , Hordeum/crescimento & desenvolvimento , Hordeum/metabolismo , Fósforo/deficiência , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Locos de Características Quantitativas/genética , Estresse Fisiológico
11.
Microbiol Res ; 227: 126296, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31421712

RESUMO

Heat shock proteins (Hsp) are important factors in the response of organisms to oscillations in environmental conditions. Although Hsp have been studied for a long time, little is known about this protein class in Trichoderma species. Here we studied the expression of Hsp genes during T. asperellum growth, and mycoparasitism against two phytopathogens: Sclerotinia sclerotiorum and Fusarium oxysporum, as well as during thermal stress. The expression levels of these genes were observed by real-time PCR and they showed to be differentially expressed under these conditions. We verified that the TaHsp26c, TaHsp70b and TaHsp70c genes were differentially expressed over time, indicating that these genes can be developmentally regulated in T. asperellum. Except for TaHsp26a, all other genes analyzed were induced in the post-contact condition when T. asperellum was cultured in a confrontation plate assay against itself. Additionally, TaHsp26b, TaHsp26c, TaHsp90, TaHsp104a and TaHsp104b were induced during initial contact between T. asperellum hyphae, suggesting that these proteins must play a role in the organism´s self-recognition mechanism. When we examined gene expression during mycoparasitism, we observed that some genes were induced both by S. sclerotiorum and F. oxysporum, while others were not induced during interaction with either of the phytopathogens. Furthermore, we observed some genes induced only during confrontation against S. sclerotiorum, indicating that the expression of Hsp genes during mycoparasitism seems to be modulated by the phytopathogen. To assess whether such genes are expressed during temperature oscillations, we analyzed their transcription levels during thermal and cold shock. We observed that except for the TaHsp70c gene, all others presented high transcript levels when T. asperellum was submitted to high temperature (38 °C), indicating their importance in the response to heat stress. The TaHsp70c gene was significantly induced only in cold shock at 4 °C. Our results show the importance of Hsp proteins during self-recognition, mycoparasitism and thermal stress in T. asperellum.


Assuntos
Regulação Fúngica da Expressão Gênica/genética , Genes Fúngicos/genética , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/fisiologia , Trichoderma/genética , Sequência de Aminoácidos , Ascomicetos/genética , Fusarium/genética , Resposta ao Choque Térmico/genética , Hifas/genética , Hifas/crescimento & desenvolvimento , Interações Microbianas , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase em Tempo Real , Alinhamento de Sequência , Estresse Fisiológico/genética , Temperatura Ambiente , Transcriptoma , Trichoderma/crescimento & desenvolvimento
12.
Microbiol Res ; 227: 126309, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31421713

RESUMO

The phosphorus availability in soil ranged from <0.01 to 1 ppm and found limiting for the utilization by plants. Hence, phosphate solubilizing bacteria (PSB) proficiently fulfill the phosphorus requirement of plants in an eco-friendly manner. The PSB encounter dynamic and challenging environmental conditions viz., high temperature, osmotic, acid, and climatic changes often hamper their activity and proficiency. The modern trend is shifting from isolation of the PSB to their genetic potentials and genome annotation not only for their better performance in the field trials but also to study their ability to cope up with stresses. In order to withstand environmental stress, bacteria need to restructure its metabolic network to ensure its survival. Pi starving condition response regulator (PhoB) and the mediator of stringent stress response alarmone (p)ppGpp known to regulate the global regulatory network of bacteria to provide balanced physiology under various stress condition. The current review discusses the global regulation and crosstalk of genes involved in phosphorus homeostasis, solubilization, and various stress response to fine tune the bacterial physiology. The knowledge of these network crosstalk help bacteria to respond efficiently to the challenging environmental parameters, and their physiological plasticity lead us to develop proficient long-lasting consortia for plant growth promotion.


Assuntos
Fenômenos Fisiológicos Bacterianos , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Guanosina Pentafosfato/metabolismo , Estresse Fisiológico , Bactérias/genética , Plasticidade Celular , Redes Reguladoras de Genes , Homeostase , Redes e Vias Metabólicas , Anotação de Sequência Molecular , Nitrogênio , Fosfatos/metabolismo , Desenvolvimento Vegetal , Plantas , Solo , Estresse Fisiológico/genética
13.
Microbiol Res ; 227: 126294, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31421718

RESUMO

After exposure to with Populus davidiana × P. alba var. pyramidalis, the expression of genes in Trichoderma asperellum were compared in four transcriptomes. The top 20 high expression genes included six heat shock proteins and three hydrophobins, indicating that Trichoderma can rapidly adapt to environment stresses and elicit a plant defense response. The genes, involved in the interaction between Trichoderma and plant, showed an increasing expression level, for example sugar transporters, EPL1s, endoxylanases, pectin lyases, and nitrilases. Interestingly, sugar transporters also showed high expression when T. asperellum was cultured on medium lacking a carbon substrate, which would contribute to T. asperellum's survival and domination in ecological niche competition. And the genes related to mycoparasitism were expressed abundantly following T. asperellum's interaction with PdPap, indicating the PdPap induction could enhance the mycoparasitic ability of T. asperellum. Twelve chitinases and five glucanases showed higher expression in transcriptome Cs, indicating that T. asperellum secretes both types of enzyme before interacting with pathogens, allowing T. asperellum to implement mycoparasitism and obtain more energy. Many novel transcripts were obtained in each transcriptome, which may play important roles in the biocontrol process of T. asperellum. Interestingly, T. asperellum undergo constitutive alternative splicing in the biocontrol process: Seven biocontrol genes were alternative spliced via intron retention. qRT-PCR analysis proved that intron retention is negatively associated with the expression of chitinase, oligopeptide transporters, and beta-lactamase. However, the percentage of MAPK intron retention was quite low, suggesting that intron retention has little effect on the function of MAPK.


Assuntos
Agentes de Controle Biológico/farmacologia , Doenças das Plantas/microbiologia , Populus/microbiologia , Transcriptoma , Trichoderma/efeitos dos fármacos , Trichoderma/genética , Trichoderma/metabolismo , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Genes Fúngicos/genética , Proteínas de Choque Térmico/genética , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/fisiologia , Estresse Fisiológico/genética
14.
Adv Exp Med Biol ; 1155: 185-196, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31468397

RESUMO

In the present study, we evaluated the antioxidant and anti-stress activities of taurine in electric foot-shock stress model rats. Taurine supplementation markedly increased the hepatic glutathione (GSH) levels, compared to the levels in the stress group. In addition, activities of antioxidant enzymes such as catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) were improved in the taurine-treated group. Plasma cortisol and dehydroepiandrosterone-sulfate (DHEA-S) levels were significantly reduced in the taurine-supplemented group compared to those in the stress group. In contrast, the levels of 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) were markedly increased in the taurine or betaine-treated group compared to those in the stress group. It may be concluded that taurine produces beneficial effects in the form of antioxidant status and biochemical alterations in foot-shock-induced acute stress in rats.


Assuntos
Antioxidantes/farmacologia , Fígado/efeitos dos fármacos , Estresse Fisiológico , Taurina/farmacologia , Animais , Catalase/metabolismo , Sulfato de Desidroepiandrosterona/sangue , Estimulação Elétrica , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Hidrocortisona/sangue , Ácido Hidroxi-Indolacético/sangue , Fígado/metabolismo , Estresse Oxidativo , Ratos , Ratos Wistar , Serotonina/sangue
15.
BMC Plant Biol ; 19(1): 345, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31390991

RESUMO

BACKGROUND: Aquaporin (AQP) proteins comprise a group of membrane intrinsic proteins (MIPs) that are responsible for transporting water and other small molecules, which is crucial for plant survival under stress conditions including salt stress. Despite the vital role of AQPs, little is known about them in cucumber (Cucumis sativus L.). RESULTS: In this study, we identified 39 aquaporin-encoding genes in cucumber that were separated by phylogenetic analysis into five sub-families (PIP, TIP, NIP, SIP, and XIP). Their substrate specificity was then assessed based on key amino acid residues such as the aromatic/Arginine (ar/R) selectivity filter, Froger's positions, and specificity-determining positions. The putative cis-regulatory motifs available in the promoter region of each AQP gene were analyzed and results revealed that their promoter regions contain many abiotic related cis-regulatory elements. Furthermore, analysis of previously released RNA-seq data revealed tissue- and treatment-specific expression patterns of cucumber AQP genes (CsAQPs). Three aquaporins (CsTIP1;1, CsPIP2;4, and CsPIP1;2) were the most transcript abundance genes, with CsTIP1;1 showing the highest expression levels among all aquaporins. Subcellular localization analysis in Nicotiana benthamiana epidermal cells revealed the diverse and broad array of sub-cellular localizations of CsAQPs. We then performed RNA-seq to identify the expression pattern of CsAQPs under salt stress and found a general decreased expression level of root CsAQPs. Moreover, qRT-PCR revealed rapid changes in the expression levels of CsAQPs in response to diverse abiotic stresses including salt, polyethylene glycol (PEG)-6000, heat, and chilling stresses. Additionally, transient expression of AQPs in N. benthamiana increased leaf water loss rate, suggesting their potential roles in the regulation of plant water status under stress conditions. CONCLUSIONS: Our results indicated that CsAQPs play important roles in response to salt stress. The genome-wide identification and primary function characterization of cucumber aquaporins provides insight to elucidate the complexity of the AQP gene family and their biological functions in cucumber.


Assuntos
Aquaporinas/fisiologia , Cucumis sativus/genética , Proteínas de Plantas/fisiologia , Aquaporinas/genética , Aquaporinas/metabolismo , Cucumis sativus/metabolismo , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Peróxido de Hidrogênio/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética , Transcriptoma , Água/metabolismo
16.
Results Probl Cell Differ ; 67: 441-485, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31435807

RESUMO

The Golgi apparatus is a central intracellular membrane-bound organelle with key functions in trafficking, processing, and sorting of newly synthesized membrane and secretory proteins and lipids. To best perform these functions, Golgi membranes form a unique stacked structure. The Golgi structure is dynamic but tightly regulated; it undergoes rapid disassembly and reassembly during the cell cycle of mammalian cells and is disrupted under certain stress and pathological conditions. In the past decade, significant amount of effort has been made to reveal the molecular mechanisms that regulate the Golgi membrane architecture and function. Here we review the major discoveries in the mechanisms of Golgi structure formation, regulation, and alteration in relation to its functions in physiological and pathological conditions to further our understanding of Golgi structure and function in health and diseases.


Assuntos
Doença , Complexo de Golgi/química , Complexo de Golgi/fisiologia , Saúde , Estresse Fisiológico , Animais , Transporte Biológico , Ciclo Celular , Humanos , Membranas Intracelulares/metabolismo
17.
Gene ; 718: 144048, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31421189

RESUMO

Main conclusion Among 247 RsAP2/ERF identified, the majority of the 21 representatives were preferably expressed under drought and heat while suppressed under heavy metals, indicating their potential roles in abiotic stress responses and tolerance. APETALA2/Ethylene-Responsive factor (AP2/ERF) transcription factor (TF) is one of the largest gene families in plants that play a fundamental role in growth and development as well as biotic and/or abiotic stresses responses. Although AP2/ERFs have been extensively characterized in many plant species, little is known about this family in radish, which is an important root vegetable with various medicinal properties. The available genome provides valuable opportunity to identify and characterize the global information on AP2/ERF TFs in radish. In this study, a total of 247 ERF family genes were identified from the radish genome, and sequence alignment and phylogenetic analyses classified the AP2/ERF superfamily into five groups (AP2, ERF, DREB, RAV and soloist). Motif analysis showed that other than AP2/ERF domains, other conserved regions were selectively distributed among different clades in the phylogenetic tree. Chromosome location analysis showed that tandem duplication may result in the expansion of RsAP2/ERF gene family. The RT-qPCR analysis confirmed that a proportion of AP2/ERF genes were preferably expressed under drought and heat stresses, whereas they were suppressed under the ABA and heavy metal stresses. These results provided valuable information for further evolutionary and functional characterization of RsAP2/ERF genes, and contributed to genetic improvement of stress tolerances in radish and other root vegetable crops.


Assuntos
Evolução Molecular , Proteínas de Homeodomínio , Metais Pesados/toxicidade , Família Multigênica , Proteínas Nucleares , Filogenia , Proteínas de Plantas , Raphanus , Estresse Fisiológico/efeitos dos fármacos , Estudo de Associação Genômica Ampla , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raphanus/genética , Raphanus/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
18.
Gene ; 718: 144018, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31454543

RESUMO

Cytosine DNA methylation (5mC) is an epigenetic mark that regulates gene expression in plant responses to environmental stresses. Zinc-finger protein (ZFP) is the largest family of DNA-binding transcription factors that also plays an essential role in eukaryote. In plant we have already identified and characterized different useful ZFP-genes. While, the main objective of this research was to observe and identify more targeted stress responsive genes of ZFPs epigenetically throughout genome in rice for the first time. A comprehensive correlation analysis was performed through methylated DNA immunoprecipitation (MeDIP)-chip hybridization in rice under salt and osmotic stresses. High salinity and drought are two major abiotic hazards that are destroying the crop world-wide. As a result, Through-out genome 14 unique stress responsive transcription factors of ZFP-genes with varying level of methylation and expression under two conditions (control vs. stress) were isolated. All the identified genes were confirmed from different databases for their specific structure, cis-regulatory elements, phylogenetic analysis, and synteny analysis. Moreover, the tissue-specific expression patterns, and expression under abiotic and phytohormones stresses were also investigated. Phylogenetically all the genes were divided into 6 distinct subgroups with Arabidopsis and orthologous proteins were find-out through synteny analysis. Available RNA-seq data in response to various phytohormones provided hormone inducible gene expression profile. Through Reverse Transcriptase qPCR (RT-qPCR) analysis tissue-specific expression in shoot and root over various time points against salt and osmotic stresses exhibited the diverse expression patterns of identified genes. Overall, the present study providing a foundation for in-depth characterization of identified genes and to further understand the epigenetic role of DNA methylation for genes expression and environmental stresses regulation in higher plant.


Assuntos
Metilação de DNA/fisiologia , DNA de Plantas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/fisiologia , Oryza , Proteínas de Plantas , Estresse Fisiológico/fisiologia , Fatores de Transcrição , DNA de Plantas/genética , DNA de Plantas/metabolismo , Estudo de Associação Genômica Ampla , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/classificação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/classificação , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
19.
Ying Yong Sheng Tai Xue Bao ; 30(8): 2600-2606, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418183

RESUMO

A greenhouse experiment was conducted to examine the photosynthetic and physiological responses of two-year-old cuttings of Hibiscus hamabo to the drought stress (20 days) and subsequent rewatering (21 days). The results showed that after 20-day drought, all individuals were survived in spite of the 5.9% soil water content. Drought stress drastically reduced net photosynthetic rate of H. hamabo, with the highest value only being 1.1 µmol·m-2·s-1. Drought stress declined the maximum photochemical efficiency to 84.3% compared with the control plants. Under drought stress, H. hamabo could stabilize cell osmotic potential and eliminate the drought-caused lipid peroxidation by coordinating the accumulation of soluble protein and antioxidant enzymes. After rewatering for seven days, net photosynthetic rate of treated H. hamabo recovered to 57.3% of that under control treatment. Meanwhile, the activities of superoxide dismutase and catalase decreased with the decline of malondialdehyde content. After rewatering for 21 days, no significant differences in the activities of antioxidant enzymes, soluble protein and relative water were found between the treated and control treatment. At harvest, the total biomass of treated H. hamabo decreased, while the root-shoot ratio remarkably increased when compared with control plants. In short, our results indicated strong drought tolerance of H. hamabo, which could play important roles in landscape improvement and greening in coastal areas.


Assuntos
Secas , Hibiscus/fisiologia , Estresse Fisiológico , Malondialdeído/metabolismo , Fotossíntese , Água
20.
Ying Yong Sheng Tai Xue Bao ; 30(8): 2767-2774, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418202

RESUMO

To reveal the physiological effects of rice alleviated by cadmium-tolerant Pseudomonas aeruginosa under cadmium stress condition, the influences of bacterial strian on the root vigor and leaf physiological characteristics were analyzed under a set of hydroponic experiments involving adding bacteria suspension, empty carrier, microbial inoculum with 20 µmol·L-1 Cd. Cadmium-free treatment as control. The results showed that the root vigor was significantly inhibited, leaf photosynthetic rate decreased, and the contents of soluble protein, flavonoid and total phenols in rice leaves were reduced, while the contents of malondialdehyde (MDA) and superoxide anion(O2-·) increased significantly under cadmium stress condition. Compared with cadmium treatment, root vigors of rice were increased by 36.1%-42.5% and 49.4%-53.0% respectively in bacteria suspension and microbial inoculum additions, net photosynthetic rates in leaves were increased by 118.5%-147.1% and 137.6%-156.9%, and the contents of soluble protein were increased by 37.0%-49.3% and 37.7%-72.6%, respectively. For the bacteria suspension treatment, the activities of SOD, POD and CAT in leaves were increased by 25.8%-36.6%, 40.9%-55.9%, 24.0%-29.2%, and the activities of SOD, POD and CAT in leaves under microbial inoculum treatment were increased by 36.9%-42.6%, 82.7%-92.6% and 43.3%-52.2%, respectively, with the stimulative effects on antioxidation enzymes in rice leaves being higher than those of bacteria suspension. Compared with cadmium treatment, the contents of MDA and O2-· in rice leaves were reduced by 44.8%-54.7%, 29.4%-41.9% and 9.9%-10.2%, 3.0%-7.1% in microbial inoculum and bacteria suspension treatments, respectively. In contrast, the contents of flavonoids and total phenols were increased by 125.4%-135.7%, 100.8%-119.4% and 139.4%-146.7%, 115.0%-134.7%, respectively. In summary, P. aeruginosa and the microbial inoculum could promote rice seedling growth by improving root vigor and photosynthetic rate, as well as the contents of flavonoids and total phenols, which led to the fact that P. aeruginosa could significantly alleviate the stress of cadmium on rice.


Assuntos
Cádmio/toxicidade , Oryza/fisiologia , Folhas de Planta/fisiologia , Raízes de Plantas/fisiologia , Pseudomonas aeruginosa/fisiologia , Poluentes do Solo/toxicidade , Oryza/microbiologia , Folhas de Planta/microbiologia , Raízes de Plantas/microbiologia , Plântula , Estresse Fisiológico
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