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1.
Annu Rev Microbiol ; 75: 515-539, 2021 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-34348026

RESUMO

To reproduce, prokaryotic viruses must hijack the cellular machinery of their hosts and redirect it toward the production of viral particles. While takeover of the host replication and protein synthesis apparatus has long been considered an essential feature of infection, recent studies indicate that extensive reprogramming of host primary metabolism is a widespread phenomenon among prokaryotic viruses that is required to fulfill the biosynthetic needs of virion production. In this review we provide an overview of the most significant recent findings regarding virus-induced reprogramming of prokaryotic metabolism and suggest how quantitative systems biology approaches may be used to provide a holistic understanding of metabolic remodeling during lytic viral infection.


Assuntos
Vírus , Células Procarióticas
2.
Trends Immunol ; 44(5): 365-371, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37061365

RESUMO

Graves' disease (GD) and Hashimoto's thyroiditis (HT) are common autoimmune diseases of the thyroid gland, causing hyperthyroidism and hypothyroidism, respectively. Despite their opposing clinical manifestation, they have several enigmatic links. Here, we propose that GD and HT have the same fundamental origin: both diseases are the cost of a beneficial physiological process called autoimmune surveillance of hypersecreting mutants. Autoreactive T cells selectively eliminate mutant cells that hypersecrete the hormones and threaten to become toxic nodules. These T cells can trigger a humoral response in susceptible individuals, leading to the production of antibodies against thyroid antigens. This shared origin can explain similarities in incidence and risk factors between HT and GD, despite their opposite clinical phenotypes.


Assuntos
Doenças Autoimunes , Doença de Graves , Doença de Hashimoto , Tireoidite Autoimune , Humanos
3.
Bioessays ; 46(8): e2300205, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38837433

RESUMO

Because of their ubiquity, plasticity, and direct effects on the nervous system, markers of oxidative status may be of great value to assess animal welfare across species and conditions in the wild. However, welfare biologists have not yet seized this opportunity, possibly because the validity of these markers as welfare indicators remains questionable. A validation process was, therefore, performed here using a meta-analytical approach considering three conditions assumed to impair the welfare of animals. With very few exceptions, two of the four considered markers consistently varied across these negatively-valenced conditions. By highlighting the current underrepresentation of markers of oxidative status in animal welfare studies, and by concretely illustrating that some of these markers can consistently reflect negative affective states, this article aims to encourage biologists to include these physiological markers in their toolbox to better measure, monitor, and perhaps also improve the welfare of animals in their natural habitat.


Assuntos
Bem-Estar do Animal , Biomarcadores , Animais , Bem-Estar do Animal/normas , Biomarcadores/metabolismo , Estresse Oxidativo , Oxirredução
4.
Dev Biol ; 510: 8-16, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38403101

RESUMO

Physiological root resorption is a common occurrence during the development of deciduous teeth in children. Previous research has shown that the regulation of the inflammatory microenvironment through autophagy in DDPSCs is a significant factor in this process. However, it remains unclear why there are variations in the autophagic status of DDPSCs at different stages of physiological root resorption. To address this gap in knowledge, this study examines the relationship between the circadian clock of DDPSCs, the autophagic status, and the periodicity of masticatory behavior. Samples were collected from deciduous teeth at various stages of physiological root resorption, and DDPSCs were isolated and cultured for analysis. The results indicate that the circadian rhythm of important autophagy genes, such as Beclin-1 and LC3, and the clock gene REV-ERBα in DDPSCs, disappears under mechanical stress. Additionally, the study found that REV-ERBα can regulate Beclin-1 and LC3. Evidence suggests that mechanical stress is a trigger for the regulation of autophagy via REV-ERBα. Overall, this study highlights the importance of mechanical stress in regulating autophagy of DDPSCs via REV-ERBα, which affects the formation of the inflammatory microenvironment and plays a critical role in physiological root resorption in deciduous teeth.


Assuntos
Relógios Circadianos , Reabsorção da Raiz , Criança , Humanos , Reabsorção da Raiz/genética , Proteína Beclina-1/genética , Ritmo Circadiano/genética , Células-Tronco , Dente Decíduo
5.
Plant J ; 117(6): 1873-1892, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38168757

RESUMO

Global climate change is predicted to result in increased yield losses of agricultural crops caused by environmental conditions. In particular, heat and drought stress are major factors that negatively affect plant development and reproduction, and previous studies have revealed how these stresses induce plant responses at physiological and molecular levels. Here, we provide a comprehensive overview of current knowledge concerning how drought, heat, and combinations of these stress conditions affect the status of plants, including crops, by affecting factors such as stomatal conductance, photosynthetic activity, cellular oxidative conditions, metabolomic profiles, and molecular signaling mechanisms. We further discuss stress-responsive regulatory factors such as transcription factors and signaling factors, which play critical roles in adaptation to both drought and heat stress conditions and potentially function as 'hubs' in drought and/or heat stress responses. Additionally, we present recent findings based on forward genetic approaches that reveal natural variations in agricultural crops that play critical roles in agricultural traits under drought and/or heat conditions. Finally, we provide an overview of the application of decades of study results to actual agricultural fields as a strategy to increase drought and/or heat stress tolerance. This review summarizes our current understanding of plant responses to drought, heat, and combinations of these stress conditions.


Assuntos
Mudança Climática , Secas , Resposta ao Choque Térmico , Produtos Agrícolas/genética , Desenvolvimento Vegetal , Estresse Fisiológico/genética
6.
Plant J ; 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39348485

RESUMO

Starch synthesis in maize endosperm adheres to the basipetal sequence from the apex downwards. However, the mechanism underlying nonuniformity among regions of the endosperm in starch accumulation and its significance is poorly understood. Here, we examined the spatiotemporal transcriptomes and starch accumulation dynamics in apical (AE), middle (ME), and basal (BE) regions of endosperm throughout the filling stage. Results demonstrated that the BE had lower levels of gene transcripts and enzymes facilitating starch synthesis, corresponding to incomplete starch storage at maturity, compared with AE and ME. Contrarily, the BE showed abundant gene expression for genetic processing and slow progress in physiological development (quantified by an index calculated from the expression values of development progress marker genes), revealing a sustained cell vitality of the BE. Further analysis demonstrated a significant parabolic correlation between starch synthesis and physiological development. An in-depth examination showed that the BE had more active signaling pathways of IAA and ABA than the AE throughout the filling stage, while ethylene showed the opposite pattern. Besides, SNF1-related protein kinase1 (SnRK1) activity, a regulator for starch synthesis modulated by trehalose-6-phosphate (T6P) signaling, was kept at a lower level in the BE than the AE and ME, corresponding to the distinct gene expression in the T6P pathway in starch synthesis regulation. Collectively, the findings support an improved understanding of the timing of starch synthesis and cell vitality in regions of the endosperm during development, and potential regulation from hormone signaling and T6P/SnRK1 signaling.

7.
Physiology (Bethesda) ; 39(2): 0, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38085014

RESUMO

The Burmese python, one of the world's largest snakes, has reached celebrity status for its dramatic physiological responses associated with digestion of enormous meals. The meals elicit a rapid gain of mass and function of most visceral organs, particularly the small intestine. There is also a manyfold elevation of oxygen consumption that demands the heart to deliver more oxygen. It therefore made intuitive sense when it was reported that the postprandial response entailed a 40% growth of heart mass that could accommodate a rise in stroke volume. Many studies, however, have not been able to reproduce the 40% growth of the heart. We collated published values on postprandial heart mass in pythons, which include several instances of no change in heart mass. On average, the heart mass is only 15% greater. The changes in heart mass did not correlate to the mass gain of the small intestine or peak oxygen consumption. Hemodynamic studies show that the rise in cardiac output does not require increased heart mass but can be fully explained by augmented cardiac filling and postprandial tachycardia. Under the assumption that hypertrophy is a contingent phenomenon, more recent experiments have employed two interventions such as feeding with a concomitant reduction in hematocrit. The results suggest that the postprandial response of the heart can be enhanced, but the 40% hypertrophy of the python heart remains elusive.


Assuntos
Boidae , Digestão , Coração , Humanos , Digestão/fisiologia , Coração/fisiologia , Hipertrofia , Hemodinâmica
8.
Physiology (Bethesda) ; 39(5): 0, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38624244

RESUMO

Significant knowledge gaps exist regarding the responses of cells, tissues, and organs to organismal death. Examining the survival mechanisms influenced by metabolism and environment, this research has the potential to transform regenerative medicine, redefine legal death, and provide insights into life's physiological limits, paralleling inquiries in embryogenesis.


Assuntos
Morte , Humanos , Animais
9.
Brain ; 147(1): 39-55, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-37691438

RESUMO

Brain perivascular macrophages are specialized populations of macrophages that reside in the space around cerebral vessels, such as penetrating arteries and venules. With the help of cutting-edge technologies, such as cell fate mapping and single-cell multi-omics, their multifaceted, pivotal roles in phagocytosis, antigen presentation, vascular integrity maintenance and metabolic regulation have more recently been further revealed under physiological conditions. Accumulating evidence also implies that perivascular macrophages are involved in the pathogenesis of neurodegenerative disease, cerebrovascular dysfunction, autoimmune disease, traumatic brain injury and epilepsy. They can act in either protective or detrimental ways depending on the disease course and stage. However, the underlying mechanisms of perivascular macrophages remain largely unknown. Therefore, we highlight potential future directions in research on perivascular macrophages, including the utilization of genetic mice and novel therapeutic strategies that target these unique immune cells for neuroprotective purposes. In conclusion, this review provides a comprehensive update on the current knowledge of brain perivascular macrophages, shedding light on their pivotal roles in central nervous system health and disease.


Assuntos
Doenças Neurodegenerativas , Camundongos , Animais , Doenças Neurodegenerativas/patologia , Encéfalo/patologia , Macrófagos/metabolismo , Sistema Nervoso Central , Fagocitose
10.
Brain ; 147(6): 2038-2052, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38195196

RESUMO

In Parkinson's disease, imbalances between 'antikinetic' and 'prokinetic' patterns of neuronal oscillatory activity are related to motor dysfunction. Invasive brain recordings from the motor network have suggested that medical or surgical therapy can promote a prokinetic state by inducing narrowband gamma rhythms (65-90 Hz). Excessive narrowband gamma in the motor cortex promotes dyskinesia in rodent models, but the relationship between narrowband gamma and dyskinesia in humans has not been well established. To assess this relationship, we used a sensing-enabled deep brain stimulator system, attached to both motor cortex and basal ganglia (subthalamic or pallidal) leads, paired with wearable devices that continuously tracked motor signs in the contralateral upper limbs. We recorded 984 h of multisite field potentials in 30 hemispheres of 16 subjects with Parkinson's disease (2/16 female, mean age 57 ± 12 years) while at home on usual antiparkinsonian medications. Recordings were done 2-4 weeks after implantation, prior to starting therapeutic stimulation. Narrowband gamma was detected in the precentral gyrus, subthalamic nucleus or both structures on at least one side of 92% of subjects with a clinical history of dyskinesia. Narrowband gamma was not detected in the globus pallidus. Narrowband gamma spectral power in both structures co-fluctuated similarly with contralateral wearable dyskinesia scores (mean correlation coefficient of ρ = 0.48 with a range of 0.12-0.82 for cortex, ρ = 0.53 with a range of 0.5-0.77 for subthalamic nucleus). Stratification analysis showed the correlations were not driven by outlier values, and narrowband gamma could distinguish 'on' periods with dyskinesia from 'on' periods without dyskinesia. Time lag comparisons confirmed that gamma oscillations herald dyskinesia onset without a time lag in either structure when using 2-min epochs. A linear model incorporating the three oscillatory bands (beta, theta/alpha and narrowband gamma) increased the predictive power of dyskinesia for several subject hemispheres. We further identified spectrally distinct oscillations in the low gamma range (40-60 Hz) in three subjects, but the relationship of low gamma oscillations to dyskinesia was variable. Our findings support the hypothesis that excessive oscillatory activity at 65-90 Hz in the motor network tracks with dyskinesia similarly across both structures, without a detectable time lag. This rhythm may serve as a promising control signal for closed-loop deep brain stimulation using either cortical or subthalamic detection.


Assuntos
Estimulação Encefálica Profunda , Ritmo Gama , Córtex Motor , Doença de Parkinson , Humanos , Doença de Parkinson/fisiopatologia , Feminino , Masculino , Pessoa de Meia-Idade , Ritmo Gama/fisiologia , Estimulação Encefálica Profunda/métodos , Córtex Motor/fisiopatologia , Idoso , Adulto , Discinesias/fisiopatologia , Discinesias/etiologia , Núcleo Subtalâmico/fisiopatologia , Rede Nervosa/fisiopatologia
11.
Proc Natl Acad Sci U S A ; 119(21): e2015576119, 2022 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-35576466

RESUMO

Pheromones exchanged by conspecifics are a major class of chemical signals that can alter behavior, physiology, and development. In particular, males and females communicate with potential mating partners via sex pheromones to promote reproductive success. Physiological and developmental mechanisms by which pheromones facilitate progeny production remain largely enigmatic. Here, we describe how a Caenorhabditis elegans male pheromone, ascr#10, improves the oogenic germline. Before most signs of aging become evident, C. elegans hermaphrodites start producing lower-quality gametes characterized by abnormal morphology, increased rates of chromosomal nondisjunction, and higher penetrance of deleterious alleles. We show that exposure to the male pheromone substantially ameliorates these defects and reduces embryonic lethality. ascr#10 stimulates proliferation of germline precursor cells in adult hermaphrodites. Coupled to the greater precursor supply is increased physiological germline cell death, which is required to improve oocyte quality in older mothers. The hermaphrodite germline is sensitive to the pheromone only during a time window, comparable in duration to a larval stage, in early adulthood. During this period, prereproductive adults assess the suitability of the environment for reproduction. Our results identify developmental events that occur in the oogenic germline in response to a male pheromone. They also suggest that the opposite effects of the pheromone on gamete quality and maternal longevity arise from competition over resource allocation between soma and the germline.


Assuntos
Caenorhabditis elegans , Senescência Celular , Oócitos , Oogênese , Atrativos Sexuais , Animais , Caenorhabditis elegans/crescimento & desenvolvimento , Senescência Celular/efeitos dos fármacos , Senescência Celular/fisiologia , Feminino , Masculino , Oócitos/efeitos dos fármacos , Oócitos/fisiologia , Oogênese/efeitos dos fármacos , Oogênese/fisiologia , Atrativos Sexuais/farmacologia , Atrativos Sexuais/fisiologia
12.
Genomics ; 116(5): 110926, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39178997

RESUMO

During sunflower growth, cold waves often occur and impede plant growth. Therefore, it is crucial to study the underlying mechanism of cold resistance in sunflowers. In this study, physiological analysis revealed that as cold stress increased, the levels of ROS, malondialdehyde, ascorbic acid, and dehydroascorbic acid and the activities of antioxidant enzymes increased. Transcriptomics further identified 10,903 DEGs between any two treatments. Clustering analysis demonstrated that the expression of MYB44a, MYB44b, MYB12, bZIP2 and bZIP4 continuously upregulated under cold stress. Cold stress can induce ROS accumulation, which interacts with hormone signals to activate cold-responsive transcription factors regulating target genes involved in antioxidant defense, secondary metabolite biosynthesis, starch and sucrose metabolism enhancement for improved cold resistance in sunflowers. Additionally, the response of sunflowers to cold stress may be independent of the CBF pathway. These findings enhance our understanding of cold stress resistance in sunflowers and provide a foundation for genetic breeding.


Assuntos
Resposta ao Choque Frio , Regulação da Expressão Gênica de Plantas , Helianthus , Plântula , Transcriptoma , Plântula/metabolismo , Plântula/genética , Helianthus/genética , Helianthus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Espécies Reativas de Oxigênio/metabolismo , Temperatura Baixa
13.
Nano Lett ; 24(23): 6906-6915, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38829311

RESUMO

Herein, a multifunctional nanohybrid (PL@HPFTM nanoparticles) was fabricated to perform the integration of chemodynamic therapy, photothermal therapy, and biological therapy over the long term at a designed location for continuous antibacterial applications. The PL@HPFTM nanoparticles consisted of a polydopamine/hemoglobin/Fe2+ nanocomplex with comodification of tetrazole/alkene groups on the surface as well as coloading of antimicrobial peptides and luminol in the core. During therapy, the PL@HPFTM nanoparticles would selectively cross-link to surrounding bacteria via tetrazole/alkene cycloaddition under chemiluminescence produced by the reaction between luminol and overexpressed H2O2 at the infected area. The resulting PL@HPFTM network not only significantly damaged bacteria by Fe2+-catalyzed ROS production, effective photothermal conversion, and sustained release of antimicrobial peptides but dramatically enhanced the retention time of these therapeutic agents for prolonged antibacterial therapy. Both in vitro and in vivo results have shown that our PL@HPFTM nanoparticles have much higher bactericidal efficiency and remarkably longer periods of validity than free antibacterial nanoparticles.


Assuntos
Antibacterianos , Nanopartículas , Antibacterianos/farmacologia , Antibacterianos/química , Animais , Nanopartículas/química , Camundongos , Escherichia coli/efeitos dos fármacos , Polímeros/química , Indóis/química , Indóis/farmacologia , Terapia Fototérmica , Humanos , Staphylococcus aureus/efeitos dos fármacos , Peptídeos Antimicrobianos/química , Peptídeos Antimicrobianos/farmacologia , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/farmacologia
14.
Am J Physiol Cell Physiol ; 327(4): C959-C978, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39183564

RESUMO

The tumor microenvironment is complex and dynamic, characterized by poor vascularization, limited nutrient availability, hypoxia, and an acidic pH. This environment plays a critical role in driving cancer progression. However, standard cell culture conditions used to study cancer cell biology in vitro fail to replicate the in vivo environment of tumors. Recently, "physiological" cell culture media that closely resemble human plasma have been developed (e.g., Plasmax, HPLM), along with more frequent adoption of physiological oxygen conditions (1%-8% O2). Nonetheless, further refinement of tumor-specific culture conditions may be needed. In this study, we describe the development of a tumor microenvironment medium (TMEM) based on murine pancreatic ductal adenocarcinoma (PDAC) tumor interstitial fluid. Using RNA-sequencing, we show that murine PDAC cells (KPCY) cultured in tumor-like conditions (TMEM, pH 7.0, 1.5% O2) exhibit profound differences in gene expression compared with plasma-like conditions (mouse plasma medium, pH 7.4, 5% O2). Specifically, the expression of genes and pathways associated with cell migration, biosynthesis, angiogenesis, and epithelial-to-mesenchymal transition were altered, suggesting tumor-like conditions promote metastatic phenotypes and metabolic remodeling. Using functional assays to validate RNA-seq data, we confirmed increased motility at 1.5% O2/TMEM, despite reduced cell proliferation. Moreover, a hallmark shift to glycolytic metabolism was identified via measurement of glucose uptake/lactate production and mitochondrial respiration. Taken together, these findings demonstrate that growth in 1.5% O2/TMEM alters several biological responses in ways relevant to cancer biology, and more closely models hallmark cancerous phenotypes in culture. This highlights the importance of establishing tumor microenvironment-like conditions in standard cancer research. NEW & NOTEWORTHY Standard cell culture conditions do not replicate the complex tumor microenvironment experienced by cells in vivo. Although currently available plasma-like media are superior to traditional supraphysiological media, they fail to model tumor-like conditions. Using RNA-seq analysis and functional metabolic and migratory assays, we show that tumor microenvironment medium (TMEM), used with representative tumor hypoxia, better models cancerous phenotypes in culture. This emphasizes the critical importance of accurately modeling the tumor microenvironment in cancer research.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Microambiente Tumoral , Animais , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/genética , Camundongos , Linhagem Celular Tumoral , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/genética , Movimento Celular , Proliferação de Células/efeitos dos fármacos , Humanos , Regulação Neoplásica da Expressão Gênica , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Glicólise , Meios de Cultura
15.
J Physiol ; 602(1): 205-222, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38059677

RESUMO

In the absence of disease, humans produce smooth and accurate movement trajectories. Despite such 'macroscopic' aspect, the 'microscopic' structure of movements reveals recurrent (quasi-rhythmic) discontinuities. To date, it is unclear how the sensorimotor system contributes to the macroscopic and microscopic architecture of movement. Here, we investigated how corticospinal excitability changes in relation to microscopic fluctuations that are naturally embedded within larger macroscopic variations in motor output. Participants performed a visuomotor tracking task. In addition to the 0.25 Hz modulation that is required for task fulfilment (macroscopic scale), the motor output shows tiny but systematic fluctuations at ∼2 and 8 Hz (microscopic scales). We show that motor-evoked potentials (MEPs) elicited by transcranial magnetic stimulation (TMS) during task performance are consistently modulated at all (time) scales. Surprisingly, MEP modulation covers a similar range at both micro- and macroscopic scales, even though the motor output differs by several orders of magnitude. Thus, corticospinal excitability finely maps the multiscale temporal patterning of the motor output, but it does so according to a principle of scale invariance. These results suggest that corticospinal excitability indexes a relatively abstract level of movement encoding that may reflect the hierarchical organisation of sensorimotor processes. KEY POINTS: Motor behaviour is organised on multiple (time)scales. Small but systematic ('microscopic') fluctuations are engrained in larger and slower ('macroscopic') variations in motor output, which are instrumental in deploying the desired motor plan. Corticospinal excitability is modulated in relation to motor fluctuations on both macroscopic and microscopic (time)scales. Corticospinal excitability obeys a principle of scale invariance, that is, it is modulated similarly at all (time)scales, possibly reflecting hierarchical mechanisms that optimise motor encoding.


Assuntos
Córtex Motor , Humanos , Córtex Motor/fisiologia , Tratos Piramidais/fisiologia , Estimulação Magnética Transcraniana/métodos , Movimento , Potencial Evocado Motor/fisiologia , Músculo Esquelético/fisiologia , Eletromiografia
16.
J Physiol ; 602(11): 2503-2510, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38160438

RESUMO

A chance mutation affecting a single or extremely few individuals in a continuous population will be quickly diluted through interbreeding. Charles Darwin fully appreciated this difficulty with relying on natural selection alone, and suggested an enabling role for geographical isolation in the origin of species. However, Darwin also believed in evolution by the inheritance of acquired traits and in populations of interbreeding animals, both of which would need a different isolating mechanism to overcome dilution and play a role in animal evolution. Historically disputed, the inheritance of acquired characters is now increasingly accepted as a phenomenon, and Charles Darwin himself is acknowledged as closely pre-empting the type of physiology necessary to mediate it in his hypothesis of 'pangenesis'. In this article, we question how the inheritance of acquired traits might overcome the problem of dilution by interbreeding and contribute to evolution. Specifically, we describe how Darwin's young protégé, George Romanes, developed ideas he discussed with Darwin and extended pangenesis to include a conceivable solution published after Darwin's death: physiological selection of fertility. In light of the 'rediscovery' of pangenesis, here we recount physiological selection as a testable hypothesis to explain how environmentally acquired characteristics could become coupled to the generation of species.


Assuntos
Seleção Genética , Animais , Especiação Genética , Evolução Biológica , Humanos , Fenótipo
17.
Plant J ; 116(3): 921-941, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37609706

RESUMO

Schrenkiella parvula, a leading extremophyte model in Brassicaceae, can grow and complete its lifecycle under multiple environmental stresses, including high salinity. Yet, the key physiological and structural traits underlying its stress-adapted lifestyle are unknown along with trade-offs when surviving salt stress at the expense of growth and reproduction. We aimed to identify the influential adaptive trait responses that lead to stress-resilient and uncompromised growth across developmental stages when treated with salt at levels known to inhibit growth in Arabidopsis and most crops. Its resilient growth was promoted by traits that synergistically allowed primary root growth in seedlings, the expansion of xylem vessels across the root-shoot continuum, and a high capacity to maintain tissue water levels by developing thicker succulent leaves while enabling photosynthesis during salt stress. A successful transition from vegetative to reproductive phase was initiated by salt-induced early flowering, resulting in viable seeds. Self-fertilization in salt-induced early flowering was dependent upon filament elongation in flowers otherwise aborted in the absence of salt during comparable plant ages. The maintenance of leaf water status promoting growth, and early flowering to ensure reproductive success in a changing environment, were among the most influential traits that contributed to the extremophytic lifestyle of S. parvula.


Assuntos
Arabidopsis , Brassicaceae , Brassicaceae/fisiologia , Arabidopsis/fisiologia , Flores , Estresse Salino , Estresse Fisiológico , Água
18.
Plant J ; 116(4): 1118-1135, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37248640

RESUMO

Field-grown crops rarely experience growth conditions in which yield can be maximized. Environmental stresses occur in combination, with advancements in crop tolerance further complicated by its polygenic nature. Strategic targeting of causal genes is required to meet future crop production needs. Here, we employed a systems biology approach in wheat (Triticum aestivum L.) to investigate physio-metabolic adjustments and transcriptome reprogramming involved in acclimations to heat, drought, salinity and all combinations therein. A significant shift in magnitude and complexity of plant response was evident across stress scenarios based on the agronomic losses, increased proline concentrations and 8.7-fold increase in unique differentially expressed transcripts (DETs) observed under the triple stress condition. Transcriptome data from all stress treatments were assembled into an online, open access eFP browser for visualizing gene expression during abiotic stress. Weighted gene co-expression network analysis revealed 152 hub genes of which 32% contained the ethylene-responsive element binding factor-associated amphiphilic repression (EAR) transcriptional repression motif. Cross-referencing against the 31 DETs common to all stress treatments isolated TaWRKY33 as a leading candidate for greater plant tolerance to combinatorial stresses. Integration of our findings with available literature on gene functional characterization allowed us to further suggest flexible gene combinations for future adaptive gene stacking in wheat. Our approach demonstrates the strength of robust multi-omics-based data resources for gene discovery in complex environmental conditions. Accessibility of such datasets will promote cross-validation of candidate genes across studies and aid in accelerating causal gene validation for crop resiliency.


Assuntos
Multiômica , Triticum , Triticum/fisiologia , Estresse Fisiológico/genética , Transcriptoma/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
19.
Pflugers Arch ; 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39354192

RESUMO

Appropriate composition of oral saliva is essential for a healthy milieu that protects mucosa and teeth. Only few studies, with small sample numbers, investigated physiological saliva ion composition in humans. We determined saliva ion composition in a sufficiently large cohort of healthy adults and analyzed the effect of physiological stimulation. We collected saliva from 102 adults under non-stimulated and physiologically stimulated conditions (chewing). Individual flow rates, pH, osmolality, Na+, K+, Cl-, and HCO3- concentrations under both conditions as well as the individual changes due to stimulation (Δvalues) were determined. Non-stimulated saliva was hypoosmolal and acidic. Na+, Cl-, and HCO3- concentrations remained well below physiological plasma values, whereas K+ concentrations exceeded plasma values more than twofold. Stimulation resulted in a doubling of flow rates and substantial increases in pH, HCO3-, and Na+ concentrations. Overall, stimulation did not considerably affect osmolality nor K+ or Cl- concentrations of saliva. An in-depth analysis of stimulation effects, using individual Δvalues, showed no correlation of Δflow rate with Δion concentrations, indicating independent regulation of acinar volume and ductal ion transport. Stimulation-induced Δ[Na+] correlated with Δ[HCO3-] and Δ[Cl-] but not with Δ[K+], indicating common regulation of ductal Na+, Cl-, and HCO3- transport. We present a robust data set of human oral saliva ion composition in healthy adults and functional insights into physiological stimulation. Our data show (i) that flow-dependence exists for Na+ and HCO3- but not for K+ and Cl- concentrations, (ii) osmolality is flow-independent, (iii) regulation of Na+, Cl-, and HCO3- transport is coupled, (iv) regulation of flow rate and ion concentrations are independent and (v) spatially separated between acini and ducts, respectively.

20.
Pflugers Arch ; 476(7): 1109-1123, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38625371

RESUMO

The myocardium is a highly oxidative tissue in which mitochondria are essential to supply the energy required to maintain pump function. When pathological hypertrophy develops, energy consumption augments and jeopardizes mitochondrial capacity. We explored the cardiac consequences of chronic swimming training, focusing on the mitochondrial network, in spontaneously hypertensive rats (SHR). Male adult SHR were randomized to sedentary or trained (T: 8-week swimming protocol). Blood pressure and echocardiograms were recorded, and hearts were removed at the end of the training period to perform molecular, imaging, or isolated mitochondria studies. Swimming improved cardiac midventricular shortening and decreased the pathological hypertrophic marker atrial natriuretic peptide. Oxidative stress was reduced, and even more interesting, mitochondrial spatial distribution, dynamics, function, and ATP were significantly improved in the myocardium of T rats. In the signaling pathway triggered by training, we detected an increase in the phosphorylation level of both AKT and glycogen synthase kinase-3 ß, key downstream targets of insulin-like growth factor 1 signaling that are crucially involved in mitochondria biogenesis and integrity. Aerobic exercise training emerges as an effective approach to improve pathological cardiac hypertrophy and bioenergetics in hypertension-induced cardiac hypertrophy.


Assuntos
Mitocôndrias Cardíacas , Condicionamento Físico Animal , Ratos Endogâmicos SHR , Animais , Masculino , Ratos , Mitocôndrias Cardíacas/metabolismo , Condicionamento Físico Animal/métodos , Condicionamento Físico Animal/fisiologia , Cardiomegalia/metabolismo , Cardiomegalia/fisiopatologia , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Natação/fisiologia , Estresse Oxidativo , Transdução de Sinais/fisiologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Pressão Sanguínea/fisiologia , Fator Natriurético Atrial/metabolismo
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