Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.021
Filtrar
Más filtros

Tipo del documento
Intervalo de año de publicación
1.
Plant J ; 119(2): 645-657, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38761364

RESUMEN

The interplay between microRNAs (miRNAs) and phytohormones allows plants to integrate multiple internal and external signals to optimize their survival of different environmental conditions. Here, we report that miR394 and its target gene LEAF CURLING RESPONSIVENESS (LCR), which are transcriptionally responsive to BR, participate in BR signaling to regulate hypocotyl elongation in Arabidopsis thaliana. Phenotypic analysis of various transgenic and mutant lines revealed that miR394 negatively regulates BR signaling during hypocotyl elongation, whereas LCR positively regulates this process. Genetically, miR394 functions upstream of BRASSINOSTEROID INSENSITIVE2 (BIN2), BRASSINAZOLEs RESISTANT1 (BZR1), and BRI1-EMS-SUPPRESSOR1 (BES1), but interacts with BRASSINOSTEROID INSENSITIVE1 (BRI1) and BRI1 SUPRESSOR PROTEIN (BSU1). RNA-sequencing analysis suggested that miR394 inhibits BR signaling through BIN2, as miR394 regulates a significant number of genes in common with BIN2. Additionally, miR394 increases the accumulation of BIN2 but decreases the accumulation of BZR1 and BES1, which are phosphorylated by BIN2. MiR394 also represses the transcription of PACLOBUTRAZOL RESISTANCE1/5/6 and EXPANSIN8, key genes that regulate hypocotyl elongation and are targets of BZR1/BES1. These findings reveal a new role for a miRNA in BR signaling in Arabidopsis.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Brasinoesteroides , Regulación de la Expresión Génica de las Plantas , Hipocótilo , MicroARNs , Transducción de Señal , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Brasinoesteroides/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Hipocótilo/crecimiento & desarrollo , Hipocótilo/genética , Hipocótilo/metabolismo , Plantas Modificadas Genéticamente , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas Quinasas
2.
Plant J ; 117(3): 747-765, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37926922

RESUMEN

Brassinazole Resistant 1 (BZR1) and bri1 EMS Suppressor 1 (BES1) are key transcription factors that mediate brassinosteroid (BR)-responsive gene expression in Arabidopsis. The BZR1/BES1 family is composed of BZR1, BES1, and four BES1/BZR1 homologs (BEH1-BEH4). However, little is known about whether BEHs are regulated by BR signaling in the same way as BZR1 and BES1. We comparatively analyzed the functional characteristics of six BZR1/BES1 family members and their regulatory mechanisms in BR signaling using genetic and biochemical analyses. We also compared their subcellular localizations regulated by the phosphorylation status, interaction with GSK3-like kinases, and heterodimeric combination. We found that all BZR1/BES1 family members restored the phenotypic defects of bri1-5 by their overexpression. Unexpectedly, BEH2-overexpressing plants showed the most distinct phenotype with enhanced BR responses. RNA-Seq analysis indicated that overexpression of both BZR1 and BEH2 regulates BR-responsive gene expression, but BEH2 has a much greater proportion of BR-independent gene expression than BZR1. Unlike BZR1 and BES1, the BR-regulated subcellular translocation of the four BEHs was not tightly correlated with their phosphorylation status. Notably, BEH1 and BEH2 are predominantly localized in the nucleus, which induces the nuclear accumulation of other BZR1/BES1 family proteins through heterodimerization. Altogether, our comparative analyses suggest that BEH1 and BEH2 play an important role in the functional interaction between BZR1/BES1 family transcription factors.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Triazoles , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Brasinoesteroides/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Regulación de la Expresión Génica de las Plantas , Glucógeno Sintasa Quinasa 3/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
3.
Plant Cell ; 34(3): 1038-1053, 2022 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-34919720

RESUMEN

Starch is the main energy storage carbohydrate in plants and serves as an essential carbon storage molecule for plant metabolism and growth under changing environmental conditions. The TARGET of RAPAMYCIN (TOR) kinase is an evolutionarily conserved master regulator that integrates energy, nutrient, hormone, and stress signaling to regulate growth in all eukaryotes. Here, we demonstrate that TOR promotes guard cell starch degradation and induces stomatal opening in Arabidopsis thaliana. Starvation caused by plants growing under short photoperiod or low light photon irradiance, as well as inactivation of TOR, impaired guard cell starch degradation and stomatal opening. Sugar and TOR induce the accumulation of ß-AMYLASE1 (BAM1), which is responsible for starch degradation in guard cells. The plant steroid hormone brassinosteroid and transcription factor BRASSINAZOLE-RESISTANT1 play crucial roles in sugar-promoted expression of BAM1. Furthermore, sugar supply induced BAM1 accumulation, but TOR inactivation led to BAM1 degradation, and the effects of TOR inactivation on BAM1 degradation were abolished by the inhibition of autophagy and proteasome pathways or by phospho-mimicking mutation of BAM1 at serine-31. Such regulation of BAM1 activity by sugar-TOR signaling allows carbon availability to regulate guard cell starch metabolism and stomatal movement, ensuring optimal photosynthesis efficiency of plants.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Carbono/metabolismo , Hormonas/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Sirolimus , Almidón/metabolismo , Azúcares/metabolismo
4.
Proc Natl Acad Sci U S A ; 119(33): e2203632119, 2022 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-35951651

RESUMEN

Epilepsy is a common neurological disorder, which has been linked to mutations or deletions of RNA binding protein, fox-1 homolog (Caenorhabditis elegans) 3 (RBFOX3)/NeuN, a neuronal splicing regulator. However, the mechanism of seizure mediation by RBFOX3 remains unknown. Here, we show that mice with deletion of Rbfox3 in gamma-aminobutyric acid (GABA) ergic neurons exhibit spontaneous seizures and high premature mortality due to increased presynaptic release, postsynaptic potential, neuronal excitability, and synaptic transmission in hippocampal dentate gyrus granule cells (DGGCs). Attenuating early excitatory gamma-aminobutyric acid (GABA) action by administering bumetanide, an inhibitor of early GABA depolarization, rescued premature mortality. Rbfox3 deletion reduced hippocampal expression of vesicle-associated membrane protein 1 (VAMP1), a GABAergic neuron-specific presynaptic protein. Postnatal restoration of VAMP1 rescued premature mortality and neuronal excitability in DGGCs. Furthermore, Rbfox3 deletion in GABAergic neurons showed fewer neuropeptide Y (NPY)-expressing GABAergic neurons. In addition, deletion of Rbfox3 in NPY-expressing GABAergic neurons lowered intrinsic excitability and increased seizure susceptibility. Our results establish RBFOX3 as a critical regulator and possible treatment path for epilepsy.


Asunto(s)
Proteínas de Unión al ADN , Neuronas GABAérgicas , Proteínas del Tejido Nervioso , Neuropéptido Y , Convulsiones , Proteína 1 de Membrana Asociada a Vesículas , Animales , Bumetanida/farmacología , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Giro Dentado/metabolismo , Antagonistas del GABA/farmacología , Neuronas GABAérgicas/metabolismo , Eliminación de Gen , Ratones , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Neuropéptido Y/metabolismo , Convulsiones/genética , Convulsiones/metabolismo , Proteína 1 de Membrana Asociada a Vesículas/genética , Proteína 1 de Membrana Asociada a Vesículas/metabolismo , Ácido gamma-Aminobutírico/metabolismo
5.
J Am Chem Soc ; 146(19): 13226-13235, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38700957

RESUMEN

Strained carbon nanohoops exhibit attractive photophysical properties due to their unique π-conjugated structure. However, incorporation of such nanohoops into the pincer ligand of metal complexes has rarely been explored. Herein, a new family of highly strained cyclometalated platinum(II) nanohoops has been synthesized and characterized. Strain-promoted C-H bond activation has been observed during the metal coordination process, and Hückel-Möbius topology and random-columnar packing in the solid state are found. Transient absorption spectroscopy revealed the size-dependent excited state properties of the nanohoops. Moreover, the nanohoops have been successfully employed as active materials in the fabrication of solution-processable resistive memory devices, including the use of the smallest platinum(II) nanohoop for the fabrication of a binary memory, with low switching threshold voltages of ca. 1.5 V, high ON/OFF current ratios, and good stability. These results demonstrate that strain incorporation into the structure can be an effective strategy to fundamentally fine-tune the reactivity, optoelectronic, and resistive memory properties.

6.
J Am Chem Soc ; 146(5): 3396-3404, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38266485

RESUMEN

Covalent organic frameworks (COFs), with the features of flexible structure regulation and easy introduction of functional groups, have aroused broad interest in the field of photocatalysis. However, due to the low light absorption intensity, low photoelectron conversion efficiency, and lack of suitable active sites, it remains a great challenge to achieve efficient photocatalytic aerobic oxidation reactions. Herein, based on reticular chemistry, we rationally designed a series of three-motif molecular junction type COFs, which formed dual photosensitizer coupled redox molecular junctions containing multifunctional COF photocatalysts. Significantly, due to the strong light adsorption ability of dual photosensitizer units and integrated oxidation and reduction features, the PY-BT COF exhibited the highest activity for photocatalytic aerobic oxidation. Especially, it achieved a photocatalytic benzylamine conversion efficiency of 99.9% in 2.5 h, which is much higher than that of the two-motif molecular junctions with only one photosensitizer or redox unit lacking COFs. The mechanism of selective aerobic oxidation was studied through comprehensive experiments and density functional theory calculations. The results showed that the photoinduced electron transfer occurred from PY and then through triphenylamine to BT. Furthermore, the thermodynamics energy for benzylamine oxidation on PY-BT COF was much lower than that for others, which confirmed the synergistic effect of dual photosensitizer coupled redox molecular junction COFs. This work provided a new strategy for the design of functional COFs with three-motif molecular junctions and also represented a new insight into the multifunctional COFs for organic catalytic reactions.

7.
Hum Mol Genet ; 31(18): 3161-3180, 2022 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-35567414

RESUMEN

RTL1/PEG11, which has been associated with anxiety disorders, is a retrotransposon-derived imprinted gene in the placenta. However, imprinting patterns and functions of RTL1 in the brain have not been well-investigated. We found Rtl1 was paternally, but not maternally, expressed in brain stem, thalamus, and hypothalamus of mice, and imprinting status of RTL1 was maintained in human brain. Paternal Rtl1 knockout (Rtl1m+/p-) mice had higher neonatal death rates due to impaired suckling, and low body weights beginning on embryonic day 16.5. High paternal expression of Rtl1 was detected in the locus coeruleus (LC) and Rtl1m+/p- mice showed an increased delay in time of onset for action potentials and inward currents with decreased neuronal excitability of LC neurons. Importantly, Rtl1m+/p- mice exhibited behaviors associated with anxiety, depression, fear-related learning and memory, social dominance, and low locomotor activity. Taken together, our findings demonstrate RTL1 is imprinted in brain, mediates emotional and social behaviors, and regulates excitability in LC neurons.


Asunto(s)
Proteínas Gestacionales , Retroelementos , Animales , Ansiedad/genética , Trastornos de Ansiedad/genética , Femenino , Impresión Genómica , Humanos , Locus Coeruleus/metabolismo , Ratones , Neuronas/metabolismo , Embarazo , Proteínas Gestacionales/genética , Proteínas Gestacionales/metabolismo , Conducta Social
8.
Biochem Biophys Res Commun ; 726: 150269, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-38909533

RESUMEN

Mitochondrial dysfunction is implicated in a wide range of human disorders including many neurodegenerative and cardiovascular diseases, metabolic diseases, cancers, and respiratory disorders. Studies have suggested the potential of l-ergothioneine (ET), a unique dietary thione, to prevent mitochondrial damage and improve disease outcome. Despite this, no studies have definitively demonstrated uptake of ET into mitochondria. Moreover, the expression of the known ET transporter, OCTN1, on the mitochondria remains controversial. In this study, we utilise mass spectrometry to demonstrate direct ET uptake in isolated mitochondria as well as its presence in mitochondria isolated from ET-treated cells and animals. Mitochondria isolated from OCTN1 knockout mice tissues, have impaired but still detectable ET uptake, raising the possibility of alternative transporter(s) which may facilitate ET uptake into the mitochondria. Our data confirm that ET can enter mitochondria, providing a basis for further work on ET in the prevention of mitochondrial dysfunction in human disease.


Asunto(s)
Ergotioneína , Ratones Noqueados , Mitocondrias , Ergotioneína/metabolismo , Ergotioneína/farmacología , Animales , Mitocondrias/metabolismo , Humanos , Ratones , Proteínas de Transporte de Catión Orgánico/metabolismo , Proteínas de Transporte de Catión Orgánico/genética , Simportadores/metabolismo , Simportadores/genética
9.
Plant Biotechnol J ; 22(7): 1989-2006, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38412139

RESUMEN

Regulation of grain size is a crucial strategy for improving the crop yield and is also a fundamental aspect of developmental biology. However, the underlying molecular mechanisms governing grain development in wheat remain largely unknown. In this study, we identified a wheat atypical basic helix-loop-helix (bHLH) transcription factor, TabHLH489, which is tightly associated with grain length through genome-wide association study and map-based cloning. Knockout of TabHLH489 and its homologous genes resulted in increased grain length and weight, whereas the overexpression led to decreased grain length and weight. TaSnRK1α1, the α-catalytic subunit of plant energy sensor SnRK1, interacted with and phosphorylated TabHLH489 to induce its degradation, thereby promoting wheat grain development. Sugar treatment induced TaSnRK1α1 protein accumulation while reducing TabHLH489 protein levels. Moreover, brassinosteroid (BR) promotes grain development by decreasing TabHLH489 expression through the transcription factor BRASSINAZOLE RESISTANT1 (BZR1). Importantly, natural variations in the promoter region of TabHLH489 affect the TaBZR1 binding ability, thereby influencing TabHLH489 expression. Taken together, our findings reveal that the TaSnRK1α1-TabHLH489 regulatory module integrates BR and sugar signalling to regulate grain length, presenting potential targets for enhancing grain size in wheat.


Asunto(s)
Brasinoesteroides , Grano Comestible , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas , Triticum , Triticum/genética , Triticum/metabolismo , Triticum/crecimiento & desarrollo , Brasinoesteroides/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Grano Comestible/genética , Grano Comestible/crecimiento & desarrollo , Grano Comestible/metabolismo , Azúcares/metabolismo , Transducción de Señal/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Estudio de Asociación del Genoma Completo
10.
J Transl Med ; 22(1): 326, 2024 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-38566102

RESUMEN

BACKGROUND: The effects of gut microbiota and metabolites on the responses to immune checkpoint inhibitors (ICIs) in advanced epidermal growth factor receptor (EGFR) wild-type non-small cell lung cancer (NSCLC) have been studied. However, their effects on EGFR-mutated (EGFR +) NSCLC remain unknown. METHODS: We prospectively recorded the clinicopathological characteristics of patients with advanced EGFR + NSCLC and assessed potential associations between the use of antibiotics or probiotics and immunotherapy efficacy. Fecal samples were collected at baseline, early on-treatment, response and progression status and were subjected to metagenomic next-generation sequencing and ultra-high-performance liquid chromatography-mass spectrometry analyses to assess the effects of gut microbiota and metabolites on immunotherapy efficacy. RESULTS: The clinical data of 74 advanced EGFR + NSCLC patients were complete and 18 patients' fecal samples were dynamically collected. Patients that used antibiotics had shorter progression-free survival (PFS) (mPFS, 4.8 vs. 6.7 months; P = 0.037); probiotics had no impact on PFS. Two dynamic types of gut microbiota during immunotherapy were identified: one type showed the lowest relative abundance at the response time point, whereas the other type showed the highest abundance at the response time point. Metabolomics revealed significant differences in metabolites distribution between responders and non-responders. Deoxycholic acid, glycerol, and quinolinic acid were enriched in responders, whereas L-citrulline was enriched in non-responders. There was a significant correlation between gut microbiota and metabolites. CONCLUSIONS: The use of antibiotics weakens immunotherapy efficacy in patients with advanced EGFR + NSCLC. The distribution characteristics and dynamic changes of gut microbiota and metabolites may indicate the efficacy of immunotherapy in advanced EGFR + NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Microbioma Gastrointestinal , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/terapia , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/tratamiento farmacológico , Inmunoterapia , Receptores ErbB/genética , Antibacterianos/uso terapéutico
11.
PLoS Pathog ; 18(10): e1010636, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36240259

RESUMEN

Wastewater-based epidemiology (WBE) is an effective way of tracking the appearance and spread of SARS-COV-2 lineages through communities. Beginning in early 2021, we implemented a targeted approach to amplify and sequence the receptor binding domain (RBD) of SARS-COV-2 to characterize viral lineages present in sewersheds. Over the course of 2021, we reproducibly detected multiple SARS-COV-2 RBD lineages that have never been observed in patient samples in 9 sewersheds located in 3 states in the USA. These cryptic lineages contained between 4 to 24 amino acid substitutions in the RBD and were observed intermittently in the sewersheds in which they were found for as long as 14 months. Many of the amino acid substitutions in these lineages occurred at residues also mutated in the Omicron variant of concern (VOC), often with the same substitutions. One of the sewersheds contained a lineage that appeared to be derived from the Alpha VOC, but the majority of the lineages appeared to be derived from pre-VOC SARS-COV-2 lineages. Specifically, several of the cryptic lineages from New York City appeared to be derived from a common ancestor that most likely diverged in early 2020. While the source of these cryptic lineages has not been resolved, it seems increasingly likely that they were derived from long-term patient infections or animal reservoirs. Our findings demonstrate that SARS-COV-2 genetic diversity is greater than what is commonly observed through routine SARS-CoV-2 surveillance. Wastewater sampling may more fully capture SARS-CoV-2 genetic diversity than patient sampling and could reveal new VOCs before they emerge in the wider human population.


Asunto(s)
COVID-19 , SARS-CoV-2 , Animales , Humanos , SARS-CoV-2/genética , Aguas Residuales , COVID-19/epidemiología , Variación Genética
12.
Hepatology ; 78(2): 389-396, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-36815353

RESUMEN

BACKGROUND AND AIMS: Genetics plays a role in the pathogenesis of intrahepatic cholestasis of pregnancy (ICP); however, empirical evidence on familial clustering of ICP is scarce. We aimed to assess the extent of familial recurrence of ICP. APPROACH AND RESULTS: This population-based cohort study included all 668,461 primiparous women who gave birth between 1995 and 2018 in Denmark. Women diagnosed with ICP were included to the index cohort. Kinship with index women was determined with the Danish Civil Registration System. Log-binomial regression was used to calculate the relative recurrence risk (RRR) of ICP in relatives of index women. A total of 6722 (1.0%) primiparous women were diagnosed with ICP. In co-twins (n=57), first-degree (n=2279), second-degree (n=1373), and third-degree (n=1758) relatives of the index women, the incidence of ICP reached 5.3%, 2.6%, 0.7%, and 1.4%, respectively, corresponding to adjusted RRRs of 4.82 (95% CI, 1.60-14.48), 2.54 (1.98-3.26), 0.81 (0.44-1.51), and 1.15 (0.77-1.71), respectively. The first-degree relatives of women who had recurrent ICP or first-trimester ICP seemed to be at higher risks [RRR, 4.30 (2.85-6.48), 3.04 (1.93-4.77), respectively]. A minor increased risk was observed in nonbiological relatives [RRR, 1.35 (1.05-1.73); n=4274, including women's full-brothers' partner and women's husbands' full sisters]. CONCLUSIONS: Co-twins and first-degree relatives of ICP patients were at ~5- and ~2.5-fold increased risk of ICP, respectively. No increased risk was observed in second-degree and third-degree relatives. Recurrent ICP and first-trimester ICP might indicate a higher degree of family clustering. Further investigation is needed to investigate the increased risk of ICP in nonbiological relatives.


Asunto(s)
Colestasis Intrahepática , Complicaciones del Embarazo , Masculino , Embarazo , Humanos , Femenino , Estudios de Cohortes , Factores de Riesgo , Complicaciones del Embarazo/epidemiología , Complicaciones del Embarazo/genética , Colestasis Intrahepática/epidemiología , Colestasis Intrahepática/genética , Análisis por Conglomerados , Dinamarca/epidemiología
13.
Plant Cell ; 33(9): 3004-3021, 2021 09 24.
Artículo en Inglés | MEDLINE | ID: mdl-34129038

RESUMEN

Nitrate is both an important nutrient and a critical signaling molecule that regulates plant metabolism, growth, and development. Although several components of the nitrate signaling pathway have been identified, the molecular mechanism of nitrate signaling remains unclear. Here, we showed that the growth-related transcription factors HOMOLOG OF BRASSINOSTEROID ENHANCED EXPRESSION2 INTERACTING WITH IBH1 (HBI1) and its three closest homologs (HBIs) positively regulate nitrate signaling in Arabidopsis thaliana. HBI1 is rapidly induced by nitrate through NLP6 and NLP7, which are master regulators of nitrate signaling. Mutations in HBIs result in the reduced effects of nitrate on plant growth and ∼22% nitrate-responsive genes no longer to be regulated by nitrate. HBIs increase the expression levels of a set of antioxidant genes to reduce the accumulation of reactive oxygen species (ROS) in plants. Nitrate treatment induces the nuclear localization of NLP7, whereas such promoting effects of nitrate are significantly impaired in the hbi-q and cat2 cat3 mutants, which accumulate high levels of H2O2. These results demonstrate that HBI-mediated ROS homeostasis regulates nitrate signal transduction through modulating the nucleocytoplasmic shuttling of NLP7. Overall, our findings reveal that nitrate treatment reduces the accumulation of H2O2, and H2O2 inhibits nitrate signaling, thereby forming a feedback regulatory loop to regulate plant growth and development.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/fisiología , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Homeostasis , Nitratos/metabolismo , Especies Reactivas de Oxígeno , Transducción de Señal , Proteínas de Arabidopsis/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo
14.
Glob Chang Biol ; 30(1): e17114, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38273577

RESUMEN

Human activity and climate change affect biodiversity and cause species range shifts, contractions, and expansions. Globally, human activities and climate change have emerged as persistent threats to biodiversity, leading to approximately 68% of the ~522 primate species being threatened with extinction. Here, we used habitat suitability models and integrated data on human population density, gross domestic product (GDP), road construction, the normalized difference vegetation index (NDVI), the location of protected areas (PAs), and climate change to predict potential changes in the distributional range and richness of 26 China's primate species. Our results indicate that both PAs and NDVI have a positive impact on primate distributions. With increasing anthropogenic pressure, species' ranges were restricted to areas of high vegetation cover and in PAs surrounded by buffer zones of 2.7-4.5 km and a core area of PAs at least 0.1-0.5 km from the closest edge of the PA. Areas with a GDP below the Chinese national average of 100,000 yuan were found to be ecologically vulnerable, and this had a negative impact on primate distributions. Changes in temperature and precipitation were also significant contributors to a reduction in the range of primate species. Under the expected influence of climate change over the next 30-50 years, we found that highly suitable habitat for primates will continue to decrease and species will be restricted to smaller and more peripheral parts of their current range. Areas of high primate diversity are expected to lose from 3 to 7 species. We recommend that immediate action be taken, including expanding China's National Park Program, the Ecological Conservation Redline Program, and the Natural Forest Protection Program, along with a stronger national policy promoting alternative/sustainable livelihoods for people in the local communities adjacent to primate ranges, to offset the detrimental effects of anthropogenic activities and climate change on primate survivorship.


Asunto(s)
Cambio Climático , Conservación de los Recursos Naturales , Animales , Humanos , Primates , Biodiversidad , Ecosistema , Actividades Humanas , China
15.
Artículo en Inglés | MEDLINE | ID: mdl-38728178

RESUMEN

A Gram-negative, facultative anaerobic, non-motile and rod-shaped bacterium, designated 10c7w1T, was isolated from a human gastrointestinal tract. Colonies on agar plates were small, circular, smooth and beige. The optimal growth conditions were determined to be 37 °C, pH 7.0-7.5 and 0 % (w/v) NaCl. Comparative analysis of complete 16S rRNA gene sequences revealed that strain 10c7w1T showed the highest sequence similarity of 95.8 % to Ottowia beijingensis MCCC 1A01410T, followed by Ottowia thiooxydans (95.2 %) JCM 11629T. The average amino acid identity values between 10c7w1T and O. beijingensis MCCC 1A01410T and O. thiooxydans JCM 11629T were above 60 % (71.4 and 69.5 %). The average nucleotide identity values between strain 10c7w1T and O. beijingensis MCCC 1A01410T and O. thiooxydans JCM 11629T were 76.9 and 72.5 %, respectively. The dominant fatty acids (≥10 %) were straight chain ones, with summed feature 3 (C16 : 1 ω7c/C16 : 1 ω6c), summed feature 8 (C18 : 1 ω7c/C18 : 1 ω6c) and C16 : 00 being the most abundant. Q-8 was the only respiratory quinone. The major polar lipids of strain 10c7w1T were phosphatidylethanolamine, diphosphatidylglycerol and unknown lipids. The DNA G+C content of strain 10c7w1T was 63.6 mol%. On the basis of phylogenetic, phenotypic and chemotaxonomic data, strain 10c7w1T is considered to represent a novel species within the genus Ottowia, for which the name Ottowia cancrivicina sp. nov. is proposed. The type strain is 10c7w1T (=MCCC 1H01399T=KCTC 92200T).


Asunto(s)
Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano , Ácidos Grasos , Filogenia , ARN Ribosómico 16S , Análisis de Secuencia de ADN , Estómago , ARN Ribosómico 16S/genética , Ácidos Grasos/química , Humanos , ADN Bacteriano/genética , Estómago/microbiología , Hibridación de Ácido Nucleico , Ubiquinona , Fosfolípidos/química
16.
J Immunol ; 209(3): 465-475, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35725270

RESUMEN

Type 1 diabetes (T1D) is an autoimmune disease characterized by T and B cell responses to proteins expressed by insulin-producing pancreatic ß cells, inflammatory lesions within islets (insulitis), and ß cell loss. We previously showed that Ag-specific tolerance targeting single ß cell protein epitopes is effective in preventing T1D induced by transfer of monospecific diabetogenic CD4 and CD8 transgenic T cells to NOD.scid mice. However, tolerance induction to individual diabetogenic proteins, for example, GAD65 (glutamic acid decarboxylase 65) or insulin, has failed to ameliorate T1D both in wild-type NOD mice and in the clinic. Initiation and progression of T1D is likely due to activation of T cells specific for multiple diabetogenic epitopes. To test this hypothesis, recombinant insulin, GAD65, and chromogranin A proteins were encapsulated within poly(d,l-lactic-co-glycolic acid) (PLGA) nanoparticles (COUR CNPs) to assess regulatory T cell induction, inhibition of Ag-specific T cell responses, and blockade of T1D induction/progression in NOD mice. Whereas treatment of NOD mice with CNPs containing a single protein inhibited the corresponding Ag-specific T cell response, inhibition of overt T1D development only occurred when all three diabetogenic proteins were included within the CNPs (CNP-T1D). Blockade of T1D following CNP-T1D tolerization was characterized by regulatory T cell induction and a significant decrease in both peri-insulitis and immune cell infiltration into pancreatic islets. As we have recently published that CNP treatment is both safe and induced Ag-specific tolerance in a phase 1/2a celiac disease clinical trial, Ag-specific tolerance induced by nanoparticles encapsulating multiple diabetogenic proteins is a promising approach to T1D treatment.


Asunto(s)
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Nanopartículas , Animales , Diabetes Mellitus Experimental/patología , Epítopos , Insulina , Ratones , Ratones Endogámicos NOD , Ratones SCID , Proteínas
17.
J Med Genet ; 60(9): 859-865, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36690427

RESUMEN

BACKGROUND: Hereditary maculopathy is a group of clinically and genetically heterogeneous disorders. With distinctive clinical features, subtypes of macular atrophy may correlate with their genetic defects. METHODS: Seven patients from six families with adolescent/adult-onset maculopathy were examined in this clinical case series. A detailed medical history and eye examination were performed. Genomic DNA sequencing was performed using whole exome sequencing or direct sequencing of retinol dehydrogenase 12 (RDH12) coding exons. RESULTS: Seven patients, including one male and six female patients, with pseudocoloboma-like maculopathy had biallelic missense RDH12 mutations. The most common mutant allele found in six of the seven patients was p.Ala269Gly. The average disease onset was at age 19.3 years, and visual acuity ranged from count fingers to 1.0. Most of the patients had mild myopic refraction. Common findings on fundus examination and spectral-domain optical coherence tomography include discrete margins of pseudocoloboma-like macular lesions with variable degrees of chorioretinal atrophy, excavation of retinal tissue and pigmentary changes mainly in the macular area. The electroretinograms were relatively normal to subnormal in all participants. CONCLUSIONS: Progressive macular degeneration with a relatively normal peripheral retina and subsequent development of a pseudocoloboma-like appearance were the main clinical features in patients with compound heterozygous RDH12 missense mutations. Genetic testing may be crucial for early diagnosis and may play a key role in the development of future treatment strategies.


Asunto(s)
Degeneración Macular , Enfermedades de la Retina , Adulto , Adolescente , Humanos , Masculino , Femenino , Adulto Joven , Mutación Missense/genética , Mutación , Análisis Mutacional de ADN , Degeneración Macular/diagnóstico , Degeneración Macular/genética , Enfermedades de la Retina/diagnóstico , Enfermedades de la Retina/genética , Atrofia , Oxidorreductasas de Alcohol/genética
18.
Proc Natl Acad Sci U S A ; 118(6)2021 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-33542102

RESUMEN

Here we report complex supramolecular tessellations achieved by the directed self-assembly of amphiphilic platinum(II) complexes. Despite the twofold symmetry, these geometrically simple molecules exhibit complicated structural hierarchy in a columnar manner. A possible key to such an order increase is the topological transition into circular trimers, which are noncovalently interlocked by metal···metal and π-π interactions, thereby allowing for cofacial stacking in a prismatic assembly. Another key to success is to use the immiscibility of the tailored hydrophobic and hydrophilic sidechains. Their phase separation leads to the formation of columnar crystalline nanostructures homogeneously oriented on the substrate, featuring an unusual geometry analogous to a rhombitrihexagonal Archimedean tiling. Furthermore, symmetry lowering of regular motifs by design results in an orthorhombic lattice obtained by the coassembly of two different platinum(II) amphiphiles. These findings illustrate the potentials of supramolecular engineering in creating complex self-assembled architectures of soft materials.

19.
Plant Dis ; 2024 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-39003505

RESUMEN

Turfgrasses are susceptible to a wide variety of ectotrophic root-infecting (ERI) fungi that cause root rot (Tredway et al., 2023). Among the root rot diseases, fairway patch, caused by Phialocephala bamuru P.T.W. Wong & C. Dong sp. nov., was recently identified and characterized in Australia infecting bermudagrass (Cynodon dactylon) and kikuyu (Pennisetum clandestinum) grass (Wong et al., 2015). Symptoms begin as small, 5-10 cm diameter patches of yellowed turf that may coalesce into larger areas of diseased grass. A characteristic sign of fairway patch is roots colonized by dark brown to black, ectotrophic mycelium. In June 2020, many tan colored, irregular-shaped patches ranging from 10-30 cm in diameter developed on a hard fescue (Festuca brevipila) cultivar 'Beacon' turfgrass field in North Brunswick, New Jersey, USA. The centers of these patches later died and became sunken or filled in partially by recovering hard fescue. The patches grew into tan irregular-shaped rings with diameters up to 3 m by Aug 2023. Symptoms were indicative of a root disease. Five 'Beacon' hard fescue soil cores at the interface of the symptomatic and non-symptomatic area were sampled in Aug 2023. Root and crown samples were observed under a dissecting microscope and dark ectotrophic hyphae were observed on both. Roots with visible ectotrophic mycelium were removed, rinsed in sterile water three times, cut into 5 mm pieces, and plated onto 10% potato dextrose agar amended with streptomycin and gentamicin at 100 mg/L (PDA+). The plates were incubated at 25°C in the dark for 5 days. The most abundant colonies being characteristic long, septate hyphae that were hyaline at the edge and dark brown to black in the center and resembled the fungus described in Wong et al., 2015. These colonies were subcultured onto PDA+ medium and selected for molecular identification. Other less abundant colonies could be identified using morphology after subcultured and had no record being pathogenic to turfgrass. To confirm the isolate's identity, its internal transcribed spacer (ITS) region was amplified in PCR using the ITS1F/ITS4 primers (Bellemain et al., 2010). The amplicon was then sequenced with both ITS1 and ITS4 primers by Sanger sequencing. Sequences were assembled (GenBank #PP000819). The consensus sequence was then BLASTn analyzed with default settings, and the result showed 99.64% sequence identity with P. bamuru (GenBank #MG195534.1). Koch's postulate was conducted in an environmentally controlled growth chamber. Six healthy 'Beacon' hard fescue plugs were sampled from the field. Three of the six plugs (treatment) were each inoculated with P. bamuru by placing 20 g of P. bamuru colonized millets beneath and around the plug before filling the pots with sand. The other three plugs (control) received the same treatment except the P. bamuru colonized millets were autoclaved. The pots were incubated in the growth chamber with a 16 h light period and 25/20°C day/night temperatures. Symptoms resembling those observed in the field appeared on the treatment pots after 21 days of incubation while the control pots remained healthy. The roots from the treatment pots were examined under the dissecting microscope to confirm the colonization of P. bamuru on the roots, and P. bamuru was reisolated and confirmed using the aforementioned morphological traits and molecular assays (GenBank #PP000820). This is the first report of a turfgrass root rot disease caused by P. bamuru in the United States. Further epidemiological, disease ecological, and pathogen biological studies are required to clarify the importance of this disease in the United States and establish proper disease containment or control measures.

20.
Int J Mol Sci ; 25(16)2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39201534

RESUMEN

The purpose of this study was to investigate whether and how albiflorin, a natural monoterpene glycoside, affects the release of glutamate, one of the most important neurotransmitters involved in neurotoxicity, from cerebrocortical nerve terminals (synaptosomes) in rats. The results showed that albiflorin reduced 4-aminopyridine (4-AP)-elicited glutamate release from synaptosomes, which was abrogated in the absence of extracellular Ca2+ or in the presence of the vesicular glutamate transporter inhibitor or a P/Q-type Ca2+ channel inhibitor, indicating a mechanism of action involving Ca2+-dependent depression of vesicular exocytotic glutamate release. Albiflorin failed to alter the increase in the fluorescence intensity of 3,3-diethylthiacarbocyanine iodide (DiSC3(5)), a membrane-potential-sensitive dye. In addition, the suppression of protein kinase A (PKA) abolished the effect of albiflorin on glutamate release. Albiflorin also reduced the phosphorylation of PKA and synaptosomal-associated protein of 25 kDa (SNAP-25) and synapsin I at PKA-specific residues, which correlated with decreased available synaptic vesicles. The results of transmission electron microscopy (TEM) also observed that albiflorin reduces the release competence of synaptic vesicles evoked by 4-AP in synaptosomes. In conclusion, by studying synaptosomally released glutamate, we suggested that albiflorin reduces vesicular exocytotic glutamate release by decreasing extracellular Ca2+ entry via P/Q-type Ca2+ channels and reducing PKA-mediated synapsin I and SNAP-25 phosphorylation.


Asunto(s)
Corteza Cerebral , Proteínas Quinasas Dependientes de AMP Cíclico , Ácido Glutámico , Sinaptosomas , Animales , Ácido Glutámico/metabolismo , Sinaptosomas/metabolismo , Sinaptosomas/efectos de los fármacos , Ratas , Corteza Cerebral/metabolismo , Corteza Cerebral/efectos de los fármacos , Masculino , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Canales de Calcio Tipo Q/metabolismo , Ratas Sprague-Dawley , Canales de Calcio Tipo P/metabolismo , Hidrocarburos Aromáticos con Puentes/farmacología , Calcio/metabolismo , Fosforilación/efectos de los fármacos , Sinapsinas/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA