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1.
Rev Environ Contam Toxicol ; 249: 1-27, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30725190

RESUMO

Metals are major abiotic stressors of many organisms, but their toxicity in plants is not as studied as in microorganisms and animals. Likewise, research in plant responses to metal contamination is sketchy. Candidate genes associated with metal resistance in plants have been recently discovered and characterized. Some mechanisms of plant adaptation to metal stressors have been now decrypted. New knowledge on microbial reaction to metal contamination and the relationship between bacterial, archaeal, and fungal resistance to metals has broadened our understanding of metal homeostasis in living organisms. Recent reviews on metal toxicity and resistance mechanisms focused only on the role of transcriptomics, proteomics, metabolomics, and ionomics. This review is a critical analysis of key findings on physiological and genetic processes in plants and microorganisms in responses to soil metal contaminations.


Assuntos
Adaptação Fisiológica/fisiologia , Ecossistema , Metais/toxicidade , Plantas , Microbiologia do Solo , Poluentes do Solo/toxicidade , Animais , Fungos , Metais Pesados , Solo
2.
J Environ Sci (China) ; 85: 46-55, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31471030

RESUMO

Natural bacterial isolates from heavily contaminated sites may evolve diverse tolerance strategies, including biosorption, efflux mechanism, and intracellular precipitation under the continually increased stress of toxic lead (Pb) from anthropogenic activities. These strategies utilize a large variety of functional groups in biological macromolecules (e.g., exopolysaccharides (EPSs) and metalloproteins) and inorganic ligands, including carboxyl, phosphate and amide groups, for capturing Pb. The amount and type of binding sites carried by biologically originated materials essentially determines their performance and potential for Pb removal and remediation. Many factors, e.g., metal ion radius, electronegativity, the shape of the cell surface sheath, temperature and pH, are thought to exert significant influences on the abovementioned interactions with Pb. Conclusively, understanding the chemical basis of Pb-binding in these bacteria can allow for the development of effective microbial Pb remediation technologies and further elucidation of Pb cycling in the environment.


Assuntos
Chumbo , Microbiologia do Solo , Poluentes do Solo , Adaptação Fisiológica , Biodegradação Ambiental , Recuperação e Remediação Ambiental
3.
BMC Plant Biol ; 19(1): 367, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31429697

RESUMO

BACKGROUND: Adaptation to abiotic stresses is crucial for the survival of perennial plants in a natural environment. However, very little is known about the underlying mechanisms. Here, we adopted a liquid culture system to investigate plant adaptation to repeated salt stress in Populus trees. RESULTS: We first evaluated phenotypic responses and found that plants exhibit better stress tolerance after pre-treatment of salt stress. Time-course RNA sequencing (RNA-seq) was then performed to profile changes in gene expression over 12 h of salt treatments. Analysis of differentially expressed genes (DEGs) indicated that significant transcriptional reprogramming and adaptation to repeated salt treatment occurred. Clustering analysis identified two modules of co-expressed genes that were potentially critical for repeated salt stress adaptation, and one key module for salt stress response in general. Gene Ontology (GO) enrichment analysis identified pathways including hormone signaling, cell wall biosynthesis and modification, negative regulation of growth, and epigenetic regulation to be highly enriched in these gene modules. CONCLUSIONS: This study illustrates phenotypic and transcriptional adaptation of Populus trees to salt stress, revealing novel gene modules which are potentially critical for responding and adapting to salt stress.


Assuntos
Adaptação Fisiológica/genética , Regulação da Expressão Gênica de Plantas , Populus/genética , Estresse Salino/genética , Transcrição Genética , Ontologia Genética , Redes Reguladoras de Genes , Genoma de Planta , Fenótipo , Populus/fisiologia , RNA de Plantas , Análise de Sequência de RNA , Transcriptoma , Árvores/genética , Árvores/fisiologia
4.
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
5.
J Microbiol ; 57(9): 717-724, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31452042

RESUMO

Salterns are hypersaline extreme environments with unique physicochemical properties such as a salinity gradient. Although the investigation of microbiota in salterns has focused on archaea and bacteria, diverse fungi also thrive in the brine and soil of salterns. Fungi isolated from salterns are represented by black yeasts (Hortaea werneckii, Phaeotheca triangularis, Aureobasidium pullulans, and Trimmatostroma salinum), Cladosporium, Aspergillus, and Penicillium species. Most studies on saltern-derived fungi gave attention to black yeasts and their physiological characteristics, including growth under various culture conditions. Since then, biochemical and molecular tools have been employed to explore adaptation of these fungi to salt stress. Genome databases of several fungi in salterns are now publicly available and being used to elucidate salt tolerance mechanisms and discover the target genes for agricultural and industrial applications. Notably, the number of enzymes and novel metabolites known to be produced by diverse saltern-derived fungi has increased significantly. Therefore, fungi in salterns are not only interesting and important subjects to study fungal biodiversity and adaptive mechanisms in extreme environments, but also valuable bioresources with potential for biotechnological applications.


Assuntos
Fungos/fisiologia , Sais/química , Cloreto de Sódio/metabolismo , Solo/química , Adaptação Fisiológica , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Tolerância ao Sal
6.
An Acad Bras Cienc ; 91(3): e20180493, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31411257

RESUMO

Leptoglossus occidentalis Heidemann is a conifer seed bug, native to North America. This species is considered invasive and has reached several countries in the Northern Hemisphere and most recently Chile in South America. This work reports the first detection of this species in Argentina, with specimens from the Rio Negro province, in 2017. Ecological traits and its potential rapid spread were also discussed.


Assuntos
Heterópteros/anatomia & histologia , Espécies Introduzidas , Adaptação Fisiológica , Animais , Argentina , Coniferophyta , Florestas , Heterópteros/crescimento & desenvolvimento
7.
An Acad Bras Cienc ; 91(3): e20180395, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31432900

RESUMO

The aquatic environment presents daily and/or seasonal variations in dissolved oxygen (DO) levels. Piava faces different DO levels in the water due to its distributional characteristics. The goal of this study was to describe the effects of low DO levels on plasma ion, biochemical and oxidative variables in piava juveniles. Fish were exposed to different DO levels, including 1.0, 2.0, 3.0, 4.0 and 5.0 mg L-1 of DO for 96 h, after which blood and tissue samples (liver, kidney, gill and muscle) were collected. The decrease in DO levels decreased plasma Na+, Cl-, K+ and NH3 levels as well as protein and glycogen levels in the liver, kidney and muscle; increased Na+/K+-ATPase activity in the gills and kidney as well as glucose and ammonia levels in the liver, kidney and muscle; and increased lactate levels in the kidney and muscle. Thiobarbituric acid-reacting substances, catalase and non-protein thiol levels decreased in the tissues of piavas exposed to low DO levels. It is concluded that piava can apparently cope with hypoxic conditions; however, low DO levels are a stressor, and the tolerance of piava to hypoxia involves iono-regulatory, metabolic and oxidative adjustments.


Assuntos
Adaptação Fisiológica/fisiologia , Caraciformes/fisiologia , Estresse Oxidativo/fisiologia , Oxigênio/fisiologia , Animais , Catalase/metabolismo , Caraciformes/metabolismo , Ácido Láctico/metabolismo , Oxigênio/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Superóxido Dismutase/metabolismo
8.
Dokl Biochem Biophys ; 486(1): 229-233, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31367828

RESUMO

The composition of fatty acids of total lipids of the outer and parenchymal parts of the pericarp in Cydonia oblonga Mill. and Mespilus germanica L. (Maloideae, Rosaceae), growing in the Northern Caucasian mountains at altitudes of 300, 500, 700, and 1200 m above sea level in various natural zones from experimental sites, was studied for the first time. It is established that the altitude of plant growth is largely correlated with the changes in the FA composition of the outer, but not the parenchymal, part of the pericarp. The nature of this variability suggests that the adaptation of plants to the conditions of significant temperature differences in the mountains is associated with the regulation of cell membrane fluidity, based on the interaction of opposite processes of synthesis of polyunsaturated and very-long-chain fatty acids.


Assuntos
Adaptação Fisiológica , Altitude , Ácidos Graxos/metabolismo , Rosaceae/metabolismo , Rosaceae/fisiologia
9.
BMC Plant Biol ; 19(1): 353, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31412775

RESUMO

BACKGROUND: The PHOSPHATE1 (PHO1) gene family plays diverse roles in inorganic phosphate (Pi) transfer and signal transduction, and plant development. However, the functions and diversification of soybean PHO1 family are poorly understood. RESULTS: Cultivated soybean (Glycine max) was domesticated from wild soybean (Glycine soja). To illuminate their roles in this evolutionary process, we comparatively investigated the G. max PHO1 genes (GmPHO1) in Suinong 14 (SN14) and G. soja PHO1 genes (GsPHO1) in ZYD00006 (ZYD6). The sequences of the orthologous Gm-GsPHO1 pairs were grouped into two Classes. The expression of Class I in both SN14 and ZYD6 was widely but relatively high in developing fruits, whereas Class II was predominantly expressed in the roots. The whole family displayed diverse response patterns to salt stresses and Pi-starvation in roots. Between SN14 and ZYD6, most PHO1 genes responded similarly to salinity stresses, and half had sharp contrasts in response to Pi-starvation, which corroborated the differential response capacities to salinity and low-Pi stress between SN14 and ZYD6. Furthermore, in transgenic Arabidopsis plants, most Class II members and GmPHO1;H9 from Class I could enhance salt tolerance, while only two Class II genes (GmPHO1;H4 and GmPHO1;H8) differently altered sensitivity to Pi-starvation. The expression of critical genes was accordingly altered in either salt or Pi signaling pathways in transgenic Arabidopsis plants. CONCLUSIONS: Our work identifies some PHO1 genes as promising genetic materials for soybean improvement, and suggests that expression variation is decisive to functional divergence of the orthologous Gm-GsPHO1 pairs, which plays an adaptive role during soybean evolution.


Assuntos
Proteínas de Transporte de Fosfato/fisiologia , Proteínas de Plantas/fisiologia , Soja/genética , Adaptação Fisiológica , Arabidopsis/genética , Evolução Molecular , Proteínas de Transporte de Fosfato/genética , Proteínas de Transporte de Fosfato/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Estresse Salino/genética , Transdução de Sinais/genética , Soja/metabolismo
10.
Biol Res ; 52(1): 46, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31434576

RESUMO

BACKGROUND: One of the most extreme environments on our planet is the Maritime Antarctic territory, due to its low-water availability, which restricts the development of plants. Sanionia uncinata Hedw. (Amblystegiaceae), the main colonizer of the Maritime Antarctic, has effective mechanisms to tolerate this environment. It has been described that the tolerance to desiccation is mediated by the hormone abscisic acid (ABA), antioxidants systems, accumulation of compatible solutes and proteins of the late embryogenesis abundant (LEA). However, to date, these mechanisms have not been described in S. uncinata. Therefore, in this work, we postulate that the tolerance to desiccation in the Antarctic moss S. uncinata is mediated by the accumulation of ABA, the osmolytes proline and glycine betaine, and dehydrins (an LEA class 11 proteins). To demonstrate our hypothesis, S. uncinata was subjected to desiccation for 24 h (loss in 95% of water content), and the effects on its physiological, photosynthetic, antioxidant and biochemical parameters were determined. RESULTS: Our results showed an accumulation of ABA in response to water loss, and the activation of protective responses that involves an increment in levels of proline and glycine betaine, an increment in the activity of antioxidant enzymes such as SOD, CAT, APX and POD, and the accumulation of dehydrins proteins. CONCLUSION: The results showed, suggest that S. uncinata is a  desiccation-tolerant moss, property mediated by high cellular plasticity regulated by ABA.


Assuntos
Antioxidantes/análise , Bryopsida/fisiologia , Dessecação , Fotossíntese/fisiologia , Adaptação Fisiológica , Regiões Antárticas , Bryopsida/química , Bryopsida/classificação , Fatores de Tempo
11.
An Acad Bras Cienc ; 91(suppl 3): e20190215, 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31460593

RESUMO

In the present context of concerns for biodiversity, the French Academy of Sciences produced in 2017 a report entitled "Mechanisms of adaptation of biodiversity to climate change and their limits". We briefly review here the production process and structure of the report, and summarize its conclusions and recommendations. The conclusions emphasize the role of habitat fragmentation in the expected impact of climate change on biodiversity, in particular for organisms with limited dispersal abilities, and the disparities in species responses which must be taken to understand the future of species assemblages ("communities") under different scenarios of climate change. The recommendations cover the organization of biodiversity research and monitoring (development of observatories, key role of embedded time scales and modeling, integration of Human and Social Sciences), as well as critical domains such as Human, animal and plant health, agriculture and forestry policies, and management of the Environment.


Assuntos
Adaptação Fisiológica , Biodiversidade , Mudança Climática , Conservação dos Recursos Naturais , Academias e Institutos , Animais , Humanos
12.
Plant Sci ; 286: 1-6, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31300135

RESUMO

The excessive and harmful light energy absorbed by the photosystem (PS) II of higher plants is dissipated as heat through a protective mechanism termed non-photochemical quenching (NPQ) of chlorophyll fluorescence. PsbS-knock-out (KO) mutants lack the trans-thylakoid proton gradient (ΔpH)-dependent part of NPQ. To elucidate the molecular mechanism of NPQ, we investigated its dependency on oxygen. The development of NPQ in wild-type (WT) rice under low-oxygen (LO) conditions was reduced to more than 50% of its original value. However, under high-oxygen (HO) conditions, the NPQ of both WT and PsbS-KO mutants recovered. Moreover, WT and PsbS-KO mutant leaves infiltrated with the ΔpH dissipating uncoupler nigericin showed increased NPQ values under HO conditions. The experiments using intact chloroplasts and protoplasts of Arabidopsis thaliana supported that the LO effects observed in rice leaves were not due to carbon dioxide deficiency. There was a noticeable 90% reduction in the half-time of P700 oxidation rate in LO-treated leaves compared with that of WT control leaves, but the HO treatment did not significantly change the half-time of P700 oxidation rate. Overall, the results obtained here indicate that the stroma of the PsbS-KO plants could be potentially under O2 deficiency. Because the functions of PsbS in rice leaves are likely to be similar to those in other higher plants, our findings offer novel insights into the role of oxygen in the development of NPQ.


Assuntos
Adaptação Fisiológica/efeitos da radiação , Arabidopsis/metabolismo , Oryza/metabolismo , Oxigênio/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Arabidopsis/efeitos da radiação , Cloroplastos/metabolismo , Cloroplastos/efeitos da radiação , Oryza/efeitos da radiação , Complexo de Proteína do Fotossistema II/genética , Folhas de Planta/genética , Folhas de Planta/fisiologia , Folhas de Planta/efeitos da radiação , Protoplastos/metabolismo , Protoplastos/efeitos da radiação
13.
Plant Sci ; 286: 37-48, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31300140

RESUMO

In this work, a non-metallicolous and a metallicolous population of S. paradoxa were exposed to copper excess and fungal elicitation, and investigated for phytohormone production and cytological alterations. Under the stress applied separately and in combination, S. paradoxa plants varied phytohormone concentration in a population-specific way, suggesting a different signalling in response to biotic and abiotic stimuli according to the environment of origin. Generally, the stress responses consisted in increased levels of salicylic acid, auxin, and gibberellin in the non-metallicolous population, and of jasmonic and abscisic acid in the metallicolous one. Interestingly, the metallicolous population increased the level of such phytohormones following exposure to the fungal elicitor only in the presence of copper. This alternative hormonal signalling could derive from the incompatibility between the ordinary ROS-mediated response to pathogens and the acquired mechanisms that prevent oxidative stress in the population from the metal-rich soil. Furthermore, stress-induced autophagic phenomena were more evident in the non-metallicolous plants than in the metallicolous ones, suggesting that the adaptation to the metalliferous environment has also affected autophagy intensity and signalling in response to copper excess and fungal elicitation.


Assuntos
Cobre/efeitos adversos , Fungos/fisiologia , Reguladores de Crescimento de Planta/metabolismo , Silene/efeitos dos fármacos , Silene/microbiologia , Poluentes do Solo/efeitos adversos , Adaptação Fisiológica , Doenças das Plantas/microbiologia , Silene/crescimento & desenvolvimento , Silene/metabolismo
14.
J Anim Sci ; 97(7): 2837-2849, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31267132

RESUMO

Ketosis is a major metabolic disorder of high-yielding dairy cows during the transition period. Although metabolic adaptations of the adipose tissue are critical for a successful transition, beyond lipolysis, alterations within adipose tissue during ketosis are not well known. The objective of this study was to investigate the adipose tissue proteome of healthy or ketotic postpartum cows to gain insights into biological adaptations that may contribute to disease outcomes. Adipose tissue biopsy was collected on 5 healthy and 5 ketotic cows at 17 (±4) d postpartum and ketosis was defined according to the clinical symptoms and serum ß-hydroxybutyrate concentration. Morphology micrographs stained by hematoxylin-eosin showed that adipocytes were smaller in ketotic cows than in healthy cows. The isobaric tag for relative and absolute quantification was applied to quantitatively identify differentially expressed proteins (DEP) in the adipose tissue. We identified a total of 924 proteins, 81 of which were differentially expressed between ketotic and healthy cows (P < 0.05 and fold changes >1.5 or <0.67). These DEP included enzymes and proteins associated with various carbohydrate, lipid, and amino acid metabolism processes. The top pathways differing between ketosis and control cows were glycolysis/gluconeogenesis, glucagon signaling pathway, cysteine and methionine metabolism, biosynthesis of amino acids, and the cGMP-PKG signaling pathway. The identified DEP were further validated by western blot and co-immunoprecipitation assay. Key enzymes associated with carbohydrate metabolism such as pyruvate kinase 2, pyruvate dehydrogenase E1 component subunit α), lactate dehydrogenase A , phosphoglucomutase 1, and 6-phosphofructokinase 1 were upregulated in ketotic cows. The expression and phosphorylation state of critical regulators of lipolysis such as perilipin-1 and hormone-sensitive lipase were also upregulated in ketotic cows. Furthermore, key proteins involved in maintaining innate immune response such as lipopolysaccharide binding protein and regakine-1 were downregulated in ketotic cows. Overall, data indicate that ketotic cows during the transition period have altered carbohydrate, lipid metabolism, and impaired immune function in the adipose tissue. This proteomics analysis in adipose tissue of ketotic cows identified several pathways and proteins that are components of the adaptation to ketosis.


Assuntos
Adaptação Fisiológica , Doenças dos Bovinos/metabolismo , Cetose/veterinária , Leite/metabolismo , Proteoma , Proteômica , Ácido 3-Hidroxibutírico/sangue , Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Animais , Biomarcadores/análise , Metabolismo dos Carboidratos , Bovinos , Feminino , Regulação da Expressão Gênica , Imunidade Inata , Cetose/metabolismo , Lactação , Metabolismo dos Lipídeos , Redes e Vias Metabólicas , Fosforilação , Período Pós-Parto , Transdução de Sinais
15.
Zool Res ; 40(4): 277-292, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31310063

RESUMO

Valentin's rock lizard (Darevskia valentini) is suggested to be the parent for several parthenogenetic species (e.g., D. armeniaca, D. bendimahiensis, D. sapphirina, and D. unisexualis) that evolved through hybridization. Complex evolutionary processes (including reticulate evolution) are occurring within the areas where Valentin's rock lizard coexists with these and other rock lizards. Hence, a detailed biological specification of this species is important for understanding how vertebrates evolve. Valentin's rock lizard is a long-lived (up to 9 years), small diurnal lizard with larger females than males, which is unlike other species of the genus. Their relatively large eggs and early reproduction period, which occurs just after emergence from winter shelters, are adaptations for living in a high elevation climate (higher than 2 000 m a.s.l.). Their body temperatures (31-32 °Ð¡) are comparable to body temperatures of rock lizards living in milder climates, though female body temperature is more dependent on substrate temperature and basking due to their lower activity than that found in males. Population density fluctuates from several individuals to several hundred per hectare and is not affected by parthenogen coexistence, although hybrids do occur in sexually biased populations where males are more common than females. The male home range is larger than that of females, though these home ranges broadly overlap. Prey is not limited in the mountain meadows and Valentin's rock lizards feed on a great variety of arthropods. Infanticide occurs in high-density populations.


Assuntos
Distribuição Animal , Lagartos/fisiologia , Adaptação Fisiológica , Animais , Armênia , Colágeno , Feminino , Lagartos/genética , Masculino , Especificidade da Espécie
16.
Sci Total Environ ; 690: 956-964, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31302559

RESUMO

In present study, a potential bacterial isolate Acetobacter pasteurianus SKYAA25 was found to be very effective in the bioconversion of apple pomace to acetic acid. The isolated strain was tolerant to high ethanol concentrations of upto 14% and temperature of 42 °C. Fermentation of apple pomace alone in presence of brewing yeast produced 7.3% of bio-ethanol which was further used for acetic acid production. Apple pomace in combination with cane molasses produced 14% of bio-ethanol. The fermented bio-ethanol was used as medium for acetic acid production which yielded 52.4 g of acetic acid/100 g of DM (Dry Matter) of apple pomace. Hence, an ecofriendly process has been developed that is entirely based on microbial processing of apple pomace to produce acetic acid without involving commercial enzymes. The present bio-conversion will prove to be beneficial for utilizing food and beverage industrial waste in the production of acetic acid.


Assuntos
Ácido Acético/metabolismo , Acetobacter/fisiologia , Adaptação Fisiológica/fisiologia , Etanol/metabolismo , Fermentação , Malus/microbiologia , Saccharomyces cerevisiae , Água/metabolismo
17.
BMC Evol Biol ; 19(1): 148, 2019 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-31331267

RESUMO

BACKGROUND: In the wake of climate change many environments will be exposed to increased and more variable temperatures. Knowledge about how species and populations respond to altered temperature regimes is therefore important to improve projections of how ecosystems will be affected by global warming, and to aid management. We conducted a common garden, split-brood temperature gradient (4.5 °C, 9.7 °C and 12.3 °C) experiment to study the effects of temperature in two populations (10 families from each population) of anadromous pike (Esox lucius) that normally experience different temperatures during spawning. Four offspring performance measures (hatching success, day degrees until hatching, fry survival, and fry body length) were compared between populations and among families. RESULTS: Temperature affected all performance measures in a population-specific manner. Low temperature had a positive effect on the Harfjärden population and a negative effect on the Lervik population. Further, the effects of temperature differed among families within populations. CONCLUSIONS: The population-specific responses to temperature indicate genetic differentiation in developmental plasticity between populations, and may reflect an adaptation to low temperature during early fry development in Harfjärden, where the stream leading up to the wetland dries out relatively early in the spring, forcing individuals to spawn early. The family-specific responses to temperature treatment indicate presence of genetic variation for developmental plasticity (G x E) within both populations. Protecting between- and within-population genetic variation for developmental plasticity and high temperature-related adaptive potential of early life history traits will be key to long-term viability and persistence in the face of continued climate change.


Assuntos
Adaptação Fisiológica , Esocidae/fisiologia , Temperatura Ambiente , Animais , Temperatura Baixa , Esocidae/anatomia & histologia , Feminino , Geografia , Masculino , Reprodução , Suécia , Água
18.
BMC Evol Biol ; 19(1): 150, 2019 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-31340758

RESUMO

BACKGROUND: Understanding how variation in gene expression contributes to morphological diversity is a major goal in evolutionary biology. Cichlid fishes from the East African Great lakes exhibit striking diversity in trophic adaptations predicated on the functional modularity of their two sets of jaws (oral and pharyngeal). However, the transcriptional basis of this modularity is not so well understood, as no studies thus far have directly compared the expression of genes in the oral and pharyngeal jaws. Nor is it well understood how gene expression may have contributed to the parallel evolution of trophic morphologies across the replicate cichlid adaptive radiations in Lake Tanganyika, Malawi and Victoria. RESULTS: We set out to investigate the role of gene expression divergence in cichlid fishes from these three lakes adapted to herbivorous and carnivorous trophic niches. We focused on the development stage prior to the onset of exogenous feeding that is critical for understanding patterns of gene expression after oral and pharyngeal jaw skeletogenesis, anticipating environmental cues. This framework permitted us for the first time to test for signatures of gene expression underlying jaw modularity in convergent eco-morphologies across three independent adaptive radiations. We validated a set of reference genes, with stable expression between the two jaw types and across species, which can be important for future studies of gene expression in cichlid jaws. Next we found evidence of modular and non-modular gene expression between the two jaws, across different trophic niches and lakes. For instance, prdm1a, a skeletogenic gene with modular anterior-posterior expression, displayed higher pharyngeal jaw expression and modular expression pattern only in carnivorous species. Furthermore, we found the expression of genes in cichlids jaws from the youngest Lake Victoria to exhibit low modularity compared to the older lakes. CONCLUSION: Overall, our results provide cross-species transcriptional comparisons of modularly-regulated skeletogenic genes in the two jaw types, implicating expression differences which might contribute to the formation of divergent trophic morphologies at the stage of larval independence prior to foraging.


Assuntos
Adaptação Fisiológica/genética , Ciclídeos/genética , Comportamento Alimentar , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Variação Genética , Arcada Osseodentária/anatomia & histologia , Animais , Ecossistema , Redes Reguladoras de Genes , Lagos , Larva/genética , Morfogênese/genética , Faringe/metabolismo , Filogenia , Padrões de Referência , Tanzânia
19.
J Strength Cond Res ; 33 Suppl 1: S140-S151, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31260419

RESUMO

Zaroni, RS, Brigatto, FA, Schoenfeld, BJ, Braz, TV, Benvenutti, JC, Germano, MD, Marchetti, PH, Aoki, MS, and Lopes, CR. High resistance-training frequency enhances muscle thickness in resistance-trained men. J Strength Cond Res 33(7S): S140-S151, 2019-The purpose of this study was to compare the effect a split training routine with muscle groups trained once per week (SPLIT) vs. whole-body split training routine with muscle groups trained 5 days per week (TOTAL) on neuromuscular adaptations in well-trained men. Eighteen healthy men (height = 177.8 ± 6.6 cm; total body mass = 84.4 ± 8.1 kg; age = 26.4 ± 4.6 years) were recruited to participate in this study. The experimental groups were matched according to baseline strength and then randomly assigned to 1 of the 2 experimental groups: SPLIT (n = 9) or TOTAL (n = 9). Prestudy and poststudy testing included 1RM for bench press, parallel back-squat and machine close-grip seated row, as well as an ultrasound analysis of the muscle thickness (MT) of the elbow flexors, triceps brachii, and vastus lateralis. After 8 weeks of training, no significant difference between groups was noted for all 1RM tests (p > 0.05). TOTAL induced a significantly greater increase in MT of the forearm flexors and vastus lateralis (p < 0.05). In conclusion, muscle strength increment is similar regardless of the experimental conditions studied; however, TOTAL may confer a potentially superior hypertrophic effect.


Assuntos
Músculo Esquelético/crescimento & desenvolvimento , Treinamento de Resistência/métodos , Fatores de Tempo , Adaptação Fisiológica , Adulto , Braço , Antebraço , Humanos , Masculino , Força Muscular , Músculo Esquelético/diagnóstico por imagem , Ultrassonografia , Adulto Jovem
20.
Oecologia ; 190(4): 941-953, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31289920

RESUMO

Climate change is affecting both the volume and distribution of precipitation, which in turn is expected to affect the growth and reproduction of plant populations. The near ubiquity of local adaptation suggests that adaptive differentiation may have important consequences for how populations are affected by and respond to changing precipitation. Here, we manipulated rainfall in a common garden to examine how differentiation among populations of common ragweed, Ambrosia artemisiifolia (Asteraceae) affects responses to water availability expected under climate change. We collected seeds from 26 populations along gradients of historical rainfall and used event-based rainout shelters and watering additions to simulate drier summer conditions and more extreme rainfall events, respectively. Ambrosia artemisiifolia had higher fitness on average under reduced rainfall, suggesting it may spread and become more abundant in areas projected to become hotter and drier during the summer months. We also found strong evidence for phenotypic and fitness clines across both latitude and longitude, and that phenological responses and fitness effects of altered rainfall depended on seed source or historical climate. The effect of rainfall treatment on female fitness was highest in western and mid longitudes, but there was little effect on eastern populations. Across latitude, the effect of rainfall treatment on male fitness was highest in southern populations. These phenology and fitness clines suggest that adaptive differentiation across the species' range has the potential to shape future responses of A. artemisiifolia populations to climate change, particularly altered patterns of rainfall.


Assuntos
Ambrosia , Aclimatação , Adaptação Fisiológica , Mudança Climática , Plantas
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