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The southeastward extrusion of Indochina along the Ailao Shan-Red River shear zone (ARSZ) is one of two of the most prominent consequences of the India-Asia collision. This plate-scale extrusion has greatly changed Southeast Asian topography and drainage patterns and effected regional climate and biotic evolution. However, little is known about how Indochina was extruded toward the southeast over time. Here, we sampled 42 plant and animal clades (together encompassing 1,721 species) that are distributed across the ARSZ and are not expected to disperse across long distances. We first assess the possible role of climate on driving the phylogenetic separations observed across the ARSZ. We then investigate the temporal dynamics of the extrusion of Indochina through a multitaxon analysis. We show that the lineage divergences across the ARSZ were most likely associated with the Indochinese extrusion rather than climatic events. The lineage divergences began at ~53 Ma and increased sharply ~35 Ma, with two peaks at ~19 Ma and ~7 Ma, and one valley at ~13 Ma. Our results suggest a two-phase model for the extrusion of Indochina, and in each phase, the extrusion was subject to periods of acceleration and decrease, in agreement with the changes of the India-Asia convergence rate and angle from the early Eocene to the late Miocene. This study highlights that a multitaxon analysis can illuminate the timing of subtle historical events that may be difficult for geological data to pinpoint and can be used to explore other tectonic events.
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Filogenia , Animais , Índia , Clima , Plantas/classificação , Rios , Sudeste Asiático , Evolução BiológicaRESUMO
BACKGROUND: Expansion and contraction of inverted repeats can cause considerable variation of plastid genomes (plastomes) in angiosperms. However, little is known about whether structural variations of plastomes are associated with adaptation to or occupancy of new environments. Moreover, adaptive evolution of angiosperm plastid genes remains poorly understood. Here, we sequenced the complete plastomes for four species of xerophytic Ceratocephala and hydrophytic Myosurus, as well as Ficaria verna. By an integration of phylogenomic, comparative genomic, and selection pressure analyses, we investigated evolutionary patterns of plastomes in Ranunculeae and their relationships with adaptation to dry and aquatic habitats. RESULTS: Owing to the significant contraction of the boundary of IRA/LSC towards the IRA, plastome sizes and IR lengths of Myosurus and Ceratocephala are smaller within Ranunculeae. Compared to other Ranunculeae, the Myosurus plastome lost clpP and rps16, one copy of rpl2 and rpl23, and one intron of rpoC1 and rpl16, and the Ceratocephala plastome added an infA gene and lost one copy of rpl2 and two introns of clpP. A total of 11 plastid genes (14%) showed positive selection, two genes common to Myosurus and Ceratocephala, seven in Ceratocephala only, and two in Myosurus only. Four genes showed strong signals of episodic positive selection. The rps7 gene of Ceratocephala and the rpl32 and ycf4 genes of Myosurus showed an increase in the rate of variation close to 3.3 Ma. CONCLUSIONS: The plastomic structure variations as well as the positive selection of two plastid genes might be related to the colonization of new environments by the common ancestor of Ceratocephala and Myosurus. The seven and two genes under positive selection might be related to the adaptation to dry and aquatic habitats in Ceratocephala and Myosurus, respectively. Moreover, intensified aridity and frequent sea-level fluctuations, as well as global cooling, might have favored an increased rate of change in some genes at about 3.3 Ma, associated with adaptation to dry and aquatic environments, respectively. These findings suggest that changing environments might have influenced structural variations of plastomes and fixed new mutations arising on some plastid genes owing to adaptation to specific habitats.
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Genomas de Plastídeos , Ranunculaceae , Evolução Molecular , Sequência de Bases , Ranunculaceae/genética , Filogenia , Genomas de Plastídeos/genéticaRESUMO
Plants are simultaneously attacked by different pests that rely on sugars uptake from plants. An understanding of the role of plant sugar allocation in these multipartite interactions is limited. Here, we characterized the expression patterns of sucrose transporter genes and evaluated the impact of targeted transporter gene mutants and brown planthopper (BPH) phloem-feeding and oviposition on root sugar allocation and BPH-reduced rice susceptibility to Meloidogyne graminicola. We found that the sugar transporter genes OsSUT1 and OsSUT2 are induced at BPH oviposition sites. OsSUT2 mutants showed a higher resistance to gravid BPH than to nymph BPH, and this was correlated with callose deposition, as reflected in a different effect on M. graminicola infection. BPH phloem-feeding caused inhibition of callose deposition that was counteracted by BPH oviposition. Meanwhile, this pivotal role of sugar allocation in BPH-reduced rice susceptibility to M. graminicola was validated on rice cultivar RHT harbouring BPH resistance genes Bph3 and Bph17. In conclusion, we demonstrated that rice susceptibility to M. graminicola is regulated by BPH phloem-feeding and oviposition on rice through differences in plant sugar allocation.
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Hemípteros , Oryza , Tylenchoidea , Animais , Feminino , Hemípteros/fisiologia , Açúcares/metabolismo , Oryza/metabolismoRESUMO
The root-knot nematode Meloidogyne graminicola secretes effectors into rice tissues to modulate host immunity. Here, we characterised MgCRT1, a calreticulin protein of M. graminicola, and identified its target in the plant. In situ hybridisation showed MgCRT1 mRNA accumulating in the subventral oesophageal gland in J2 nematodes. Immunolocalization indicated MgCRT1 localises in the giant cells during parasitism. Host-induced gene silencing of MgCRT1 reduced the infection ability of M. graminicola, while over-expressing MgCRT1 enhanced rice susceptibility to M. graminicola. A yeast two-hybrid approach identified the calmodulin-like protein OsCML31 as an interactor of MgCRT1. OsCML31 interacts with the high mobility group protein OsHMGB1 which is a conserved DNA binding protein. Knockout of OsCML31 or overexpression of OsHMGB1 in rice results in enhanced susceptibility to M. graminicola. In contrast, overexpression of OsCML31 or knockout of OsHMGB1 in rice decreases susceptibility to M. graminicola. The GST-pulldown and luciferase complementation imaging assay showed that MgCRT1 decreases the interaction of OsCML31 and OsHMGB1 in a competitive manner. In conclusion, when M. graminicola infects rice and secretes MgCRT1 into rice, MgCRT1 interacts with OsCML31 and decreases the association of OsCML31 with OsHMGB1, resulting in the release of OsHMGB1 to enhance rice susceptibility.
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Oryza , Tylenchoidea , Animais , Doenças das Plantas , Calmodulina/metabolismo , Oryza/metabolismo , Calreticulina/genéticaRESUMO
The integration of morphological and molecular data is essential to understand the affinities of fossil taxa and spatio-temporal evolutionary processes of organisms. However, homoplastic morphological characters can mislead the placement of fossil taxa and impact downstream analyses. Here, we provide an example of how to mitigate effectively the effect of morphological homoplasy on the placement of fossil taxa and biogeographic inferences of Cissampelideae. We assembled three data types, morphological data only, morphological data with a molecular scaffold and combined morphological and molecular data. By removing high-level homoplastic morphological data or reweighting the morphological characters, we conducted 15 parsimony, 12 undated Bayesian and four dated Bayesian analyses. Our results show that the 14 selected Cissampelideae fossil taxa are placed poorly when based only on morphological data, but the addition of molecular scaffold and combination of morphological and molecular data greatly improve the resolution of fossil nodes. We raise the monotypic Stephania subg. Botryodiscia to generic status and discover that three fossils previously assigned to Stephania should be members of Diploclisia. The Bayesian tip-dated tree recovered by removing homoplastic morphological characters with a Rescaled Consistency Index <0.25 has the highest stratigraphic fit and consequently generates more reasonable biogeographic reconstruction for Cissampelideae. Cissampelideae began to diversify in Asia in the latest Cretaceous and subsequently dispersed to South America around the Cretaceous-Palaeogene boundary. Two dispersal events from Asia to Africa occurred in the Early Eocene and the Late Eocene-Late Oligocene, respectively. These findings provide guidelines and practical methods for mitigating the effects of homoplastic morphological characters on fossil placements and Bayesian tip-dating, as well as insights into the past tropical floristic exchanges among different continents.
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Menispermaceae , Filogenia , Menispermaceae/anatomia & histologia , Menispermaceae/genética , Teorema de Bayes , Filogeografia , Fósseis , Fatores de TempoRESUMO
OBJECTIVE: The present work concentrated on validating whether sinomenine alleviates bleomycin (BLM)-induced pulmonary fibrosis, inflammation, and oxidative stress. METHODS: A rat model of pulmonary fibrosis was constructed through intratracheal injection with 5 mg/kg BLM, and the effects of 30 mg/kg sinomenine on pulmonary inflammation, fibrosis, apoptosis, and 4-hydroxynonenal density were evaluated by hematoxylin and eosin staining, Masson's trichrome staining, TUNEL staining, and immunohistochemistry. Hydroxyproline content and concentrations of inflammatory cytokines and oxidative stress markers were detected using corresponding kits. MRC-5 cells were treated with 10 ng/ml PDGF, and the effects of 1 mM sinomenine on cell proliferation were assessed by EdU assays. The mRNA expression of inflammatory cytokines and the protein levels of collagens, fibrosis markers, and key markers involved in the TLR4/NLRP3/TGFß signaling were tested with RT-qPCR and immunoblotting analysis. RESULTS: Sinomenine attenuated pulmonary fibrosis and inflammation while reducing hydroxyproline content and the protein expression of collagens and fibrosis markers in BLM-induced pulmonary fibrosis rats. Sinomenine reduced apoptosis in lung samples of BLM-challenged rats by increasing Bcl-2 and reducing Bax and cleaved caspase-3 protein expression. In addition, sinomenine alleviated inflammatory response and oxidative stress in rats with pulmonary fibrosis induced by BLM. Moreover, sinomenine inhibited the TLR4/NLRP3/TGFß signaling pathway in lung tissues of BLM-stimulated rats. Furthermore, TLR4 inhibitor, TAK-242, attenuated PDGF-induced fibroblast proliferation and collagen synthesis in MRC-5 cells. CONCLUSION: Sinomenine attenuates BLM-caused pulmonary fibrosis, inflammation, and oxidative stress by inhibiting the TLR4/NLRP3/TGFß signaling, indicating that sinomenine might become a therapeutic candidate to treat pulmonary fibrosis.
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Bleomicina , Morfinanos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Estresse Oxidativo , Fibrose Pulmonar , Transdução de Sinais , Receptor 4 Toll-Like , Fator de Crescimento Transformador beta , Animais , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/metabolismo , Morfinanos/farmacologia , Morfinanos/uso terapêutico , Bleomicina/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Receptor 4 Toll-Like/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Masculino , Transdução de Sinais/efeitos dos fármacos , Ratos Sprague-Dawley , Linhagem Celular , Ratos , Humanos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/metabolismoRESUMO
Myocardial ischemia/reperfusion (I/R) decreases cardiac function and efficiency. Accumulating evidence suggests that long noncoding RNAs (lncRNAs) have been linked to the cellular processes of myocardial I/R injury. The present investigation elucidated the function of lncRNA colon cancer-associated transcript 2 (CCAT2) in myocardial I/R injury and the related mechanisms.AC16 cardiomyocytes were exposed to hypoxia (16 hours) /reoxygenation (6 hours) (H/R) to mimic myocardial I/R models in vitro. CCAT2 and microRNA (miR) -539-3p expressions in AC16 cardiomyocytes were measured using real-time quantitative polymerase chain reaction. B-cell-specific Moloney murine leukemia virus insertion region 1 (BMI1) protein levels in AC16 cardiomyocytes were determined by western blotting. Cell viability, lactate dehydrogenase (LDH) leakage, reactive oxygen species (ROS) levels, mitochondrial membrane potential, and apoptosis were detected using Counting Kit-8, LDH Assay Kit, dihydroethidium assay, 5,5',6,6'-tetrachloro1,1',3,3'-tetramethylbenzimidazolylcarbocyanine iodide staining, flow cytometry, and western blotting, respectively. The interactions between the molecules were confirmed using the dual-luciferase gene reporter. The wingless/integrated/beta-catenin (Wnt/ß-catenin) pathway under the H/R condition was detected by western blotting.CCAT2 and BMI1 mRNA expressions were reduced in H/R-exposed AC16 cardiomyocytes. CCAT2 overexpression exerted protective effects against H/R-induced cardiomyocyte injury, as demonstrated by increased cell viability and mitochondrial membrane potential and decreased LDH leakage, ROS levels, and apoptosis. In addition, CCAT2 positively regulated BMI1 expression by binding to miR-539-3p. CCAT2 knockdown or miR-539-3p overexpression restrained the protective effects of BMI1 against H/R-induced cardiomyocyte injury. In addition, miR-539-3p overexpression reversed the protective effects of CCAT2. Furthermore, CCAT2 activated the Wnt/ß-catenin pathway under the H/R condition via the miR-539-3p/BMI1 axis.Overall, this investigation showed the protective effects of the CCAT2/miR-539-3p/BMI1/Wnt/ß-catenin regulatory axis against cardiomyocyte injury induced by H/R.
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Neoplasias do Colo , Doença da Artéria Coronariana , MicroRNAs , Isquemia Miocárdica , Traumatismo por Reperfusão Miocárdica , RNA Longo não Codificante , Animais , Humanos , Camundongos , Apoptose/fisiologia , beta Catenina/metabolismo , Neoplasias do Colo/metabolismo , Doença da Artéria Coronariana/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Isquemia Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Complexo Repressor Polycomb 1/genética , Espécies Reativas de Oxigênio/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismoRESUMO
Applying chemical enhanced oil recovery (EOR) to shale and tight formations is expected to accelerate China's Shale Revolution as it did in conventional reservoirs. However, its screening and modeling are more complex. EOR operations are faced with choices of chemicals including traditional surfactant solutions, surfactant solutions in the form of micro-emulsions (nano-emulsions), and nano-fluids, which have similar effects to surfactant solutions. This study presents a systematic comparative analysis composed of laboratory screening and numerical modeling. It was conducted on three scales: tests of chemical morphology and properties, analysis of micro-oil-displacing performance, and simulation of macro-oil-increasing effect. The results showed that although all surfactant solutions had the effects of reducing interfacial tension, altering wettability, and enhancing imbibition, the nano-emulsion with the lowest hydrodynamic radius is the optimal selection. This is attributed to the fact that the properties of the nano-emulsion match well with the characteristics of these shale and tight reservoirs. The nano-emulsion is capable of integrating into the tight matrix, interacting with the oil and rock, and supplying the energy for oil to flow out. This study provides a comprehensive understanding of the role that surfactant solutions could play in the EOR of unconventional reservoirs.
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BACKGROUND: Ferroptosis plays an essential role in lipopolysaccharide (LPS)-induced acute lung injury (ALI). Meteorin-like/Meteorin-ß (Metrnß) is a protein secreted by skeletal muscle and adipose tissue and plays a role in cardiovascular diseases. However, its role in acute lung injury has not been elucidated. METHODS: In this study, we used an adenovirus (Ad) delivery system to overexpress or knockdown Metrnß in lung tissue to examine the role of Metrnß in LPS-induced acute lung injury. RESULTS: We found that ferroptosis was increased during LPS-induced ALI. The expression of Metrnß was reduced in ALI lung tissue. Overexpression of Metrnß in lung tissue alleviated LPS-induced lung injury, inflammation, and ferroptosis. Moreover, Metrnß knockout in lung tissue accelerated LPS-induced ALI, inflammation, and ferroptosis. We also cultured MLE-12 cells and transfected the cells with Ad-Metrnß or Metrnß siRNA. Metrnß overexpression ameliorated LPS-induced MLE cell death, inflammation and ferroptosis, while Metrnß knockdown aggregated cell survival and decreased inflammation and ferroptosis. Moreover, we found that Metrnß enhanced ferroptosis-related Gpx4 expression and reduced ferroportin and ferritin levels. Furthermore, we found that Metrnß positively regulated SIRT1 transcription thus inhibited P53, increased SLC7A11 expression. When we used the ferroptosis inhibitor ferrostatin-1, the deteriorating effects of Metrnß knockout were abolished in ALI mice. Moreover, SIRT1 knockout also abolished the protective effects of Metrnß overexpression in vivo. CONCLUSIONS: Taken together, Metrnß could protect LPS-induced ALI by activating SIRT1-P53- SLC7A11 mediated ferroptosis inhibition.
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Lesão Pulmonar Aguda , Ferroptose , Animais , Camundongos , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/metabolismo , Inflamação/genética , Inflamação/metabolismo , Lipopolissacarídeos , Sirtuína 1/genética , Sirtuína 1/metabolismo , Proteína Supressora de Tumor p53RESUMO
Angiosperms, a trigger for the Cretaceous Terrestrial Revolution (KTR), underwent a rapid expansion and occupied all the environments during the Mid-Upper Cretaceous. Yet, Cretaceous biogeographic patterns and processes underlying the distribution of angiosperm diversity in the Northern Hemisphere are still poorly known. Here, we elucidated the biogeographic diversification of the angiosperm family Papaveraceae, an ancient Northern Hemisphere clade characterized by poor dispersal ability and high level of regional endemism. Based on both plastome and multi-locus datasets, we reconstructed a robust time-calibrated phylogeny that includes all currently recognized 45 genera of this family. Within the time-calibrated phylogenetic framework, we conducted 72 biogeographic analyses by testing the sensitivity of uncertainties of area delimitation, maxarea constraints, and the parameters of the model, i.e., j (describing jump-dispersal events) and w (modifying dispersal multiplier matrices), to ancestral range estimations. We also inferred ancestral habitat and ecological niches. Phylogenetic analyses strongly support Papaveraceae as monophyletic. Pteridophylloideae is strongly supported as sister to Hypecoideae-Fumarioideae. Our results indicate that the j parameter and number of predefined areas strongly affect ancestral range estimates, generating questionable ancestral ranges, whereas maxarea constraint and w parameter have no effect and improve model fit. After accounting for these uncertainties, our results indicate that Papaveraceae differentiated in Asian wet forests during the Lower Cretaceous and subsequently occupied the Asian and western North American arid and open areas. Three dispersals from Asia to western North America via the Bering land bridge occurred in the Mid-Upper Cretaceous, largely in agreement with the KTR. Habitat shift and ecological niche divergence resulted in the subsequent disjunctions between Asia and western North America. These findings suggest that the interplay of range expansion and niche divergence-driven vicariance might have shaped Cretaceous biogeographic patterns of angiosperms with Papaveraceae-like ecological requirements and dispersal abilities in the Northern Hemisphere, hence contributing to the knowledge on the geographic expansion of angiosperms during the KTR.
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Magnoliopsida , Papaver , Papaveraceae , Filogenia , FilogeografiaRESUMO
Rapid diversification of a group is often associated with exploiting an ecological opportunity and/or the evolution of a key innovation. However, how the interplay of such abiotic and biotic factors correlates with organismal diversification has been rarely documented in empirical studies, especially for organisms inhabiting drylands. Fumarioideae is the largest subfamily in Papaveraceae and is mainly distributed in temperate regions of the Northern Hemisphere. Here, we used one nuclear (ITS) and six plastid (rbcL, atpB, matK, rps16, trnL-F, and trnG) DNA sequences to investigate the spatio-temporal patterns of diversification and potential related factors of this subfamily. We first present the most comprehensive phylogenetic analysis of Fumarioideae to date. The results of our integrated molecular dating and biogeographic analyses indicate that the most recent common ancestor of Fumarioideae started to diversify in Asia during the Upper Cretaceous, and then dispersed multiple times out of Asia in the Cenozoic. In particular, we discover two independent dispersal events from Eurasia to East Africa in the late Miocene, suggesting that the Arabian Peninsula might be an important exchange corridor between Eurasia and East Africa in the late Miocene. Within the Fumarioideae, increased speciation rates were detected in two groups, Corydalis and Fumariinae. Corydalis first experienced a burst of diversification in its crown group at â¼ 42 Ma, and further accelerated diversification from the mid-Miocene onwards. During these two periods, Corydalis had evolved diverse life history types, which could have facilitated the colonization of diverse habitats originating from extensive orogenesis in the Northern Hemisphere as well as Asian interior desertification. Fumariinae underwent a burst of diversification at â¼ 15 Ma, which temporally coincides with the increasing aridification in central Eurasia, but is markedly posterior to the shifts in habitat (from moist to arid) and in life history (from perennial to annual) and to range expansion from Asia to Europe, suggesting that Fumariinae species may have been pre-adapted to invade European arid habitats by the acquisition of annual life history. Our study provides an empirical case that documents the importance of pre-adaptation on organismal diversification in drylands and highlights the significant roles of the synergy of abiotic and biotic factors in promoting plant diversification.
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Papaveraceae , Filogenia , Ásia , Ecossistema , Sequência de Bases , FilogeografiaRESUMO
The deciduous broad-leaved forests (DBLFs) cover large temperate and subtropical high-altitude regions in the Northern Hemisphere. They are home to rich biodiversity, especially to numerous endemic and relict species. However, we know little about how this vegetation in the Northern Hemisphere has developed through time. Here, we used Actaea (Ranunculaceae), an herbaceous genus almost exclusively growing in the understory of the Northern Hemisphere DBLFs, to shed light on the historical assembly of this biome in the Northern Hemisphere. We present a complete species-level phylogenetic analysis of Actaea based on five plastid and nuclear loci. Using the phylogenetic framework, we estimated divergence times, ancestral ranges, and diversification rates. Phylogenetic analyses strongly support Actaea as monophyletic. Sections Podocarpae and Oligocarpae compose a clade, sister to all other Actaea. The sister relationship between sections Chloranthae and Souliea is strongly supported. Section Dichanthera is not monophyletic unless section Cimicifuga is included. Actaea originated in East Asia, likely the Qinghai-Tibet Plateau, in the late Paleocene (c. 57 Ma), and subsequently dispersed into North America in the middle Eocene (c. 43 Ma) via the Thulean bridge. Actaea reached Europe twice, Japan twice, and Taiwan once, and all these five colonization events occurred in the late Miocene-early Pliocene, a period when sea level dropped. Actaea began to diversify at c. 43 Ma. The section-level diversification took place at c. 27-37 Ma and the species-level diversification experienced accelerations twice, which occurred at c. 15 Ma and c. 5 Ma, respectively. Our findings suggest that the Northern Hemisphere DBLFs might have risen in the middle Eocene and further diversified in the late Eocene-Oligocene, middle Miocene and early Pliocene, in association with climatic deterioration during these four periods.
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Actaea , Ranunculaceae , Filogenia , Filogeografia , FlorestasRESUMO
BACKGROUND AND AIMS: Modern tropical rainforests house the highest biodiversity of Earth's terrestrial biomes and are distributed in three low-latitude areas. However, the biogeographical patterns and processes underlying the distribution of biodiversity among these three areas are still poorly known. Here, we used Tiliacoreae, a tribe of pantropical lianas with a high level of regional endemism, to provide new insights into the biogeographical relationships of tropical rainforests among different continents. METHODS: Based on seven plastid and two nuclear DNA regions, we reconstructed a phylogeny for Tiliacoreae with the most comprehensive sampling ever. Within the phylogenetic framework, we then estimated divergence times and investigated the spatiotemporal evolution of the tribe. KEY RESULTS: The monophyletic Tiliacoreae contain three major clades, which correspond to Neotropical, Afrotropical and Indo-Malesian/Australasian areas, respectively. Both Albertisia and Anisocycla are not monophyletic. The most recent common ancestor of Tiliacoreae occurred in Indo-Malesia, the Afrotropics and Neotropics in the early Eocene, then rapidly diverged into three major clades between 48 and 46 Ma. Three dispersals from Indo-Malesia to Australasia were inferred, one in the middle Eocene and two in the late Oligocene-late Miocene, and two dispersals from the Afrotropics to Indo-Malesia occurred in the late Eocene-Oligocene. CONCLUSIONS: The three main clades of Anisocycla correspond to three distinct genera [i.e. Anisocycla sensu stricto and two new genera (Georgesia and Macrophragma)]. Epinetrum is a member of Albertisia. Our findings highlight that sea-level fluctuations and climate changes in the Cenozoic have played important roles in shaping the current distribution and endemism of Tiliacoreae, hence contributing to the knowledge on the historical biogeography of tropical rainforests on a global scale.
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Menispermaceae , Floresta Úmida , Filogenia , Filogeografia , Menispermaceae/genética , Plastídeos/genéticaRESUMO
As a common flavonols, kaempferol (Kae) has a broad market as health food and medicine for its anti-inflammatory, anti-oxidation, and anti-cancer properties. In this study, a novel convenient and simple fluorescent sensor based on carbon dots (CDs) for the detection of Kae was developed. The fluorescent CDs, with excellent photo-luminescence (PL) and up-conversion luminescence (UCPL) properties, were successfully prepared by low-temperature oil bath reaction based on ascorbic acid as carbon source at 90 °C in one pot. Under the optimal conditions, the fluorescence (FL) intensity of CDs was gradually quenched by the increasing addition of Kae with a linear relationship between F0/F and Kae concentration in a wide range from 5 µM to 100 µM with a detection limit of 0.38 µM. And this designed sensor was favourably applied for the detection of Kae in actual sample (xin-da-kang tablets). Moreover, the proposed CDs has great application prospects as a drug-sensor for detecting Kae due to its simple operation, economical and green materials, low equipment requirement, and rapid detection.
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Pontos Quânticos , Temperatura , Quempferóis , Carbono , Corantes FluorescentesRESUMO
As a possible alternative to lead halide perovskites, inorganic mixed-valence Au-based halide perovskites have drawn much attention. In the current research, we have conducted comprehensive theoretical calculations to reveal the structural feature, thermodynamic and dynamic stability, mechanical behavior, optoelectronic properties, and photovoltaic performance of Au-based halide perovskites A2AuIAuIIIX6 (A = Rb, Cs; X = Cl, Br, I). The structural parameters of these compounds are carefully analyzed. Our calculations indicate that the thermodynamic, dynamic, and mechanical stability of monoclinic Rb2AuIAuIIIX6 and tetragonal Cs2AuIAuIIIX6 are ensured, and they are all ductile. The electronic band structure analysis shows that Rb2AuIAuIIII6 illustrates a direct-gap feature, while Rb2AuIAuIIIX6 (X = Cl, Br) and Cs2AuIAuIIIX6 (X = Cl, Br, I) are indirect-gap materials. The effect of A-site cation substitution on the optical band gaps of the Au-based halide perovskites is elucidated. Our results further suggest that Rb2AuIAuIIIX6 (X = Br, I) and Cs2AuIAuIIIX6 (X = Cl, Br, I) are more suitable for single-junction solar cells due to their suitable band gaps within 1.1-1.5 eV. Furthermore, four compounds A2AuIAuIIIX6 (A = Rb, Cs; X = Br, I) not only have high absorption coefficients in the visible region but also show excellent photovoltaic performance, especially for A2AuIAuIIII6 (A = Rb, Cs), whose efficiency can reach over 29% with a film thickness of 0.5 µm. Our study suggests that inorganic Au-based halide perovskites are potential alternatives for optoelectronic devices in solar cells.
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Chalcogenide perovskites have recently attracted enormous attention since they show promising optoelectronic properties and high stability for photovoltaic applications. Herein, the relative stability and photoactive properties of chalcogenide perovskites AZrX3 (A = Ca, Sr, Ba; X = S, Se) including the needle-like (α phase) and distorted perovskite (ß phase) structures are first revealed. The results show that the difference in the relative stability is large between the α and ß phases for both AZrS3 and AZrSe3. The fundamental direct-gap transition is only allowed for the ß phase, which is further confirmed by its optical properties. It is indicated that the suitable direct-gap energy of the α phase is not desirable for thin-film solar cells. Therefore, the stability, and mechanical, electronic, and optical properties of the distorted chalcogenide perovskites AZrS3-xSex (x = 0, 1, 2, 3) are mainly explored for the first time. The predicted direct band gaps of nine compounds AZrS3-xSex (x = 1-3) are in the ideal range of 1.3-1.7 eV. Most compounds have small effective masses, low exciton binding energies, and high optical absorption coefficients in the visible region. Moreover, the mechanical, thermodynamic, and dynamic stabilities are identified for these compounds. Our findings suggest that CaZrSe3, SrZrSe3, and BaZrSe3 are proposed to be the most promising candidates for photovoltaic applications owing to their promising properties.
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The use of bacteriophages (phages) for antibacterial therapy is under increasing consideration to treat antimicrobial-resistant infections. Phages have evolved multiple mechanisms to target their bacterial hosts, such as high-affinity, environmentally hardy receptor-binding proteins. However, traditional phage therapy suffers from multiple challenges stemming from the use of an exponentially replicating, evolving entity whose biology is not fully characterized (e.g., potential gene transduction). To address this problem, we conjugate the phages to gold nanorods, creating a reagent that can be destroyed upon use (termed "phanorods"). Chimeric phages were engineered to attach specifically to several Gram-negative organisms, including the human pathogens Escherichia coli, Pseudomonas aeruginosa, and Vibrio cholerae, and the plant pathogen Xanthomonas campestris The bioconjugated phanorods could selectively target and kill specific bacterial cells using photothermal ablation. Following excitation by near-infrared light, gold nanorods release energy through nonradiative decay pathways, locally generating heat that efficiently kills targeted bacterial cells. Specificity was highlighted in the context of a P. aeruginosa biofilm, in which phanorod irradiation killed bacterial cells while causing minimal damage to epithelial cells. Local temperature and viscosity measurements revealed highly localized and selective ablation of the bacteria. Irradiation of the phanorods also destroyed the phages, preventing replication and reducing potential risks of traditional phage therapy while enabling control over dosing. The phanorod strategy integrates the highly evolved targeting strategies of phages with the photothermal properties of gold nanorods, creating a well-controlled platform for systematic killing of bacterial cells.
Assuntos
Antibacterianos/administração & dosagem , Bacteriófagos/fisiologia , Ouro/química , Hipertermia Induzida , Nanotubos/química , Terapia por Fagos/métodos , Infecções por Pseudomonas/terapia , Animais , Cães , Farmacorresistência Bacteriana Múltipla , Humanos , Raios Infravermelhos , Células Madin Darby de Rim Canino , Nanopartículas Metálicas/química , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/fisiologiaRESUMO
Root-knot nematodes of the genus Meloidogyne parasitize the roots of thousands of plants and can cause severe damage and yield loss. Here, we report a new root-knot nematode, Meloidogyne limonae n. sp., parasitizing "lemon" (Citrus limon) in Hainan Province, South China. Lemon trees infected by the root-knot nematode showed poor-quality lemons, chlorosis of foliage, weak growth, and numerous root galls with white females and egg masses protruding outside. Phylogenetic trees of sequences within the ribosomal and mitochondria DNA demonstrated that this species differs clearly from other previously described root-knot nematodes. Morphologically, the new species is characterized by an oval-shaped perineal pattern and the lateral field marked by a ridge of cuticle on one or both sides, the dorsal arch is low with fine to coarse, smooth cuticle striae, vulva slit centrally located at the unstriated area; spicules of males are arcuate, curved ventrally; gubernaculum is distinct and curved; labial disc of second-stage juveniles is prominent and dumbbell-shaped; stylet knobs oval and sloping backwardly; pharyngeal glands not filling the body cavity, overlapping intestine ventrally; conical tail gradually tapering. Phylogenetic trees based on ITS1-5.8S-ITS2, D2-D3 of the 28S rDNA, and the COI and COII-16S rRNA genes of the mtDNA showed that Meloidogyne limonae n. sp. belongs to an undescribed root-knot nematode lineage that is separated from other species with the resemblance in morphology, such as M. floridensis M. hispanica, M. acronea, and M. paranaenis.
RESUMO
The cereal cyst nematodes Heterodera avenae and Heterodera filipjevi are recognized as cyst nematodes that infect cereal crops and cause severe economic losses worldwide. Rapid, visual detection of cyst nematodes is essential for more effective control of this pest. In this study, recombinase polymerase amplification (RPA) combined with clustered regularly interspaced short palindromic repeats (CRISPR)/Cas12a (formerly known as cpf1) was developed for the rapid detection of H. avenae and H. filipjevi from infested field samples. The RPA reaction was performed at a wide range of temperatures from 35 to 42°C within 15 min. There was no cross-reactivity between H. avenae, H. filipjevi, and the common closely related plant-parasitic nematodes, indicating the high specificity of this assay. The detection limit of RPA-Cas12a was as low as 10-4 single second-stage juvenile (J2), 10-5 single cyst, and 0.001 ng of genomic DNA, which is 10 times greater than that of RPA-lateral flow dipstick (LFD) detection. The RPA-Cas12a assay was able to detect 10-1 single J2 of H. avenae and H. filipjevi in 10 g of soil. In addition, the RPA-LFD assay and RPA-Cas12a assays could both quickly detect H. avenae and H. filipjevi from naturally infested soil, and the entire detection process could be completed within 1 h. These results indicated that the RPA-Cas12a assay developed herein is a simple, rapid, specific, sensitive, and visual method that can be easily adapted for the quick detection of H. avenae and H. filipjevi in infested fields.
Assuntos
Recombinases , Tylenchoidea , Animais , Sistemas CRISPR-Cas , Grão Comestível/parasitologia , SoloRESUMO
The distribution range of root-knot nematode Meloidogyne graminicola is rapidly expanding, posing a severe threat to rice production. In this study, the sequences of cytochrome oxidase subunit I (COI) genes of rice M. graminicola populations from all reported provinces in China were amplified and sequenced by PCR. The distribution pattern and phylogenetic tree showed that all 54 M. graminicola populations in China have distinct geographical distribution characteristics; specifically, cluster 1 (southern China), cluster 2 (central south and southwest China), and cluster 3 (central and eastern China). The high haplotype diversity (Hd = 0.646) and low nucleotide diversity (π = 0.00682), combined with the negative value of Tajima's D (-1.252) and Fu's Fs (-3.06764), suggested that all nematode populations were expanding. The existence of high genetic differentiation (Fst = 0.5933) and low gene flow (Nm = 0.3333) indicated that there was a block of gene exchange between most populations. Mutation accumulation with population expansion might be directly responsible for the high genetic differentiation; therefore, the tested nematode population showed high within-group genetic variation (96.30%). The haplotype Hap8 was located at the bottom of the network topology, with the widest distribution and the highest frequency (59.26%), indicating that it was the ancestral haplotype. The populations in cluster 3 were newly invasive according to the lowest frequency of occurrence of Hap8, the highest number of endemic haplotypes, and the highest total haplotype frequency (60%). In contrast, cluster 1 having the highest genetic diversity (Hd = 0.772, π = 0.01127) indicated that it was the most primitive. Interestingly, the highest gene flow (Nm > 1), lowest genetic differentiation (Fst ≤ 0.33), and closest genetic distance (0.000) only occurred between the Guangdong/Hainan population and others, which suggested that there might be channels for gene exchange between them and that long-distance dispersal occurred. This suggestion is further confirmed by the weak correlation between genetic distance and geographical distance. Based on these data, a hypothesis can be drawn that M. graminicola populations in China were spreading from south to north, specifically from Guangdong and Hainan Provinces to other regions. Natural selection (including anthropogenic) and genetic drift were the main drivers of their evolution. Coincidentally, this hypothesis was consistent with the gradual warming trend and the chronological order of reporting these populations. The main factors influencing current M. graminicola population expansion and distribution patterns might be geography, climate, long-distance seedling transport, interregional operations of agricultural machinery, and rotation mode. It reminds human beings of the necessity to be vigilant about preventing nematode disease according to local conditions all year round.