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1.
Nature ; 546(7656): 124-128, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28569818

RESUMO

Materials can be transformed from one crystalline phase to another by using an electric field to control ion transfer, in a process that can be harnessed in applications such as batteries, smart windows and fuel cells. Increasing the number of transferrable ion species and of accessible crystalline phases could in principle greatly enrich material functionality. However, studies have so far focused mainly on the evolution and control of single ionic species (for example, oxygen, hydrogen or lithium ions). Here we describe the reversible and non-volatile electric-field control of dual-ion (oxygen and hydrogen) phase transformations, with associated electrochromic and magnetoelectric effects. We show that controlling the insertion and extraction of oxygen and hydrogen ions independently of each other can direct reversible phase transformations among three different material phases: the perovskite SrCoO3-δ (ref. 12), the brownmillerite SrCoO2.5 (ref. 13), and a hitherto-unexplored phase, HSrCoO2.5. By analysing the distinct optical absorption properties of these phases, we demonstrate selective manipulation of spectral transparency in the visible-light and infrared regions, revealing a dual-band electrochromic effect that could see application in smart windows. Moreover, the starkly different magnetic and electric properties of the three phases-HSrCoO2.5 is a weakly ferromagnetic insulator, SrCoO3-δ is a ferromagnetic metal, and SrCoO2.5 is an antiferromagnetic insulator-enable an unusual form of magnetoelectric coupling, allowing electric-field control of three different magnetic ground states. These findings open up opportunities for the electric-field control of multistate phase transformations with rich functionalities.

2.
BMC Biol ; 20(1): 110, 2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35549721

RESUMO

BACKGROUND: Mosquitoes locate a human host by integrating various sensory cues including odor, thermo, and vision. However, their innate light preference and its genetic basis that may predict the spatial distribution of mosquitoes, a prerequisite to encounter a potential host and initiate host-seeking behaviors, remains elusive. RESULTS: Here, we first studied mosquito visual features and surprisingly uncovered that both diurnal (Aedes aegypti and Aedes albopictus) and nocturnal (Culex quinquefasciatus) mosquitoes significantly avoided stronger light when given choices. With consistent results from multiple assays, we found that such negative phototaxis maintained throughout development to adult stages. Notably, female mosquitoes significantly preferred to bite hosts in a shaded versus illuminated area. Furthermore, silencing Opsin1, a G protein-coupled receptor that is most enriched in compound eyes, abolished light-evoked avoidance behavior of Aedes albopictus and attenuated photonegative behavior in Aedes aegypti. Finally, we found that field-collected Aedes albopictus also prefers darker area in an Opsin1-dependent manner. CONCLUSIONS: This study reveals that mosquitoes consistently prefer darker environment and identifies the first example of a visual molecule that modulates mosquito photobehavior.


Assuntos
Aedes , Culex , Aedes/fisiologia , Animais , Aprendizagem da Esquiva , Culex/fisiologia , Comportamento Alimentar , Feminino , Humanos
3.
J Sci Food Agric ; 103(1): 380-388, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35894931

RESUMO

BACKGROUND: Studies have found that the addition of plant essential oils to feed had a positive effect on intestinal microflora and immunity in mice. However, the effect of different ways of ingestion of orange essential oil on mice has seldom been reported. In the present study, we investigated the effects of ingestion of orange essential oil by gavage, sniffing and feeding on intestinal microflora and immunity in mice. RESULTS: The results obtained showed that a low concentration of essential oil feeding significantly increased the spleen index of mice (P < 0.05). The effect of different ways of ingestion on the thymus index, immunoglobulin G and immunoglobulin M of mice was not significant (P > 0.05). High and medium concentrations of essential oil feeding increased the level of interleukin-2 in mice (P < 0.05). H+ K+ -ATPase activity was significantly increased in mice fed with gavage and different concentrations of essential oil feed compared to the control group (P < 0.05). The analysis of the results of the microflora in the cecum and colon of mice indicated that the medium concentration of essential oil feeding group and the sniffing group significantly changed the structure of the flora and increased the diversity of the intestinal microflora. All three essential oil ingestion methods increased the abundance of Bacteroidetes and Lactobacillus in the intestine of mice. CONCLUSION: Compared with gavage and feeding, sniffing had a significant effect on immunoglobulins in mice. All the three ingestion methods could affect the intestinal microflora of mice and increase the abundance of Lactobacillus. © 2022 Society of Chemical Industry.


Assuntos
Microbioma Gastrointestinal , Óleos Voláteis , Óleos Voláteis/farmacologia , Lactobacillus , Intestinos , Ceco
4.
Appl Microbiol Biotechnol ; 106(13-16): 5123-5136, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35771244

RESUMO

The plasma membrane H+-ATPase (PMA1) is a major cytosolic pH regulator and a potential candidate for antifungal drug discovery due to its fungal specificity and criticality. In this study, the function of Penicillum digitatum PMA1 was characterized through RNA interference (RNAi) and overexpression technology. The results showed that silencing the PMA1 gene reduces cell growth and pathogenicity, and increases susceptibility of P. digitatum to proton pump inhibitors (PPIs). Under scanning electron microscopy (SEM) and transmission electron microscopy (TEM) examination, cell morphology was significantly altered in the PMA1- silenced mutant (si57). When compared with wild type (WT) and the overexpressed mutant (oe9), the cell walls of the si57 mutant were thicker and their cell membrane damage manifested particularly at sites of polarized growth. Consistent with the morphological change on the cell wall, chitin and glucan content of the cell wall of si57 were significantly lower and accompanied with increased activities of chitinase and glucanase. The lower ergosterol content in the si57 mutant then increased cell membrane permeability, ultimately leading to leakage of cytoplasmic contents such as ions, reduced sugars and soluble proteins. Furthermore, significantly decreased activity of cell wall degrading enzymes of si57 during citrus fruit infections indicates a reduced pathogenicity in this mutant. We conclude that PMA1 in P. digitatum plays an important role in maintaining pathogenesis and PMA1 could be a candidate novel fungicidal drug discovery for citrus green mold. KEY POINTS: Silencing PMA1 gene decreased the growth and pathogenicity of P. digitatum. Silencing PMA1 gene damaged cell wall and cell membrane integrity of P. digitatum. PMA1 appears to be a suitable fungicidal target against citrus green mold.


Assuntos
Citrus , Penicillium , Antifúngicos/metabolismo , Antifúngicos/farmacologia , Membrana Celular/metabolismo , Penicillium/metabolismo , Doenças das Plantas/microbiologia , ATPases Translocadoras de Prótons/genética , ATPases Translocadoras de Prótons/metabolismo , Virulência
5.
Sensors (Basel) ; 22(10)2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35632359

RESUMO

The accurate identification of overlapping Agaricus bisporus in a factory environment is one of the challenges faced by automated picking. In order to better segment the complex adhesion between Agaricus bisporus, this paper proposes a segmentation recognition algorithm for overlapping Agaricus bisporus. This algorithm calculates the global gradient threshold and divides the image according to the image edge gradient feature to obtain the binary image. Then, the binary image is filtered and morphologically processed, and the contour of the overlapping Agaricus bisporus area is obtained by edge detection in the Canny operator, the convex hull and concave area are extracted for polygon simplification, and the vertices are extracted using Harris corner detection to determine the segmentation point. After dividing the contour fragments by the dividing point, the branch definition algorithm is used to merge and group all the contours of the same Agaricus bisporus. Finally, the least squares ellipse fitting algorithm and the minimum distance circle fitting algorithm are used to reconstruct the outline of Agaricus bisporus, and the demand information of Agaricus bisporus picking is obtained. The experimental results show that this method can effectively overcome the influence of uneven illumination during image acquisition and be more adaptive to complex planting environments. The recognition rate of Agaricus bisporus in overlapping situations is more than 96%, and the average coordinate deviation rate of the algorithm is less than 1.59%.


Assuntos
Agaricus , Algoritmos , Análise dos Mínimos Quadrados
6.
J Food Sci Technol ; 59(11): 4487-4498, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36193467

RESUMO

Nootkatone is an important functional sesquiterpene, which can be obtained by the biotransformation of valencene. It is increasingly important because of its pleasant citrus aroma and physiological effects. Yarrowia lipolytica is beneficial for biotechnology applications and has ability to transform valencene to nootkatone. High-speed counter-current chromatography (HSCCC) was used to isolate and purify the product of nootkatone in this study. The suitable two-phase solvent system was selected and the optimum separation conditions were determined. The partition coefficients of nootkatone and the separation factor between nootkatone and valencene were considered as the indexes. The results showed that there were numerous products during the transformation of valencene by Yarrowia lipolytica, and the content of nootkatone was 13.75%. The obtained nootkatone was separated by HSCCC with a solvent system n-hexane/methanol/water (5/4/1, v/v). The final purity of nootkatone was 91.61 ± 0.20% and the elution time was 290-310 min. The structure of nootkatone was identified by gas chromatography-mass spectrometry (GC-MS), infrared spectrum and nuclear magnetic resonance hydrogen spectroscopy (1H NMR). This was the first report on the separation of nootkatone from the fermentation broth by HSCCC. This study proved that HSCCC could be used as an effective method to separate and purify the nootkatone from valencene transformed by Yarrowia lipolytica with n-hexane/methanol/water (5/4/1, v/v).

7.
Pestic Biochem Physiol ; 179: 104957, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34802536

RESUMO

The antifungal activity of postharvest kiwifruit against the pathogen Botryosphaeria dothidea was evaluated for 33 essential oil monomers. The possible mechanism for the known active compounds were further assessed in this study. The results show all the EO components exhibit inhibitory effects on the pathogen to different degrees except for Farnesol. Carbon chain length and C2-C3 double bonds had a great effect on the antifungal activities of aldehydes. Of all of these, carvacrol had the strongest antifungal activity with EC50 of 12.58 µL/L and EC90 of 22.08 µL/L. Carvacrol also exhibits significant inhibitory effects on the pathogen, both in vivo and in vitro. Carvacrol evidently alters the hyphal morphology of B. dothidea and severely damages cell membrane and inhibits the formation of lipid components on the membrane. As cell membrane permeability increases, intracellular homeostasis including ion and biomacromolecules were destroyed by carvacrol. Furthermore, carvacrol appears to significantly inhibit mitochondrial activity and respiration rates, resulting in cell death of B. dothidea. Our results provide evidence that carvacrol could be a very useful compound for controlling postharvest rot soft in kiwifruit.


Assuntos
Ascomicetos , Óleos Voláteis , Frutas , Doenças das Plantas
8.
Pestic Biochem Physiol ; 167: 104534, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32527431

RESUMO

The physiological and iTRAQ-based proteomic analyses were used to reveal the inhibitory roles of pinocembrin on mitochondria of P. italicum and its cell death mechanism. The results show that pinocembrin damages both mitochondrial structure and function. 167 and 807 differentially expressed proteins (DEPs) were detected in P. italicum mycelia after treatment with pinocembrin for 8 h and 24 h respectively, and the DEPs were significantly enriched in the oxidative phosphorylation (OXPHOS) pathway, especially for mitochondrial respiratory chain (MRC) complexes I and V. Furthermore, the expression levels of proteins related to programmed cell death (PCD) were significantly up-regulated in mycelia with Pinocembrin incubation for 24 h. Combined with the results of physio-chemical analysis, the data revealed that pinocembrin targeted MRC complexes I and V, to induce ATP depletion, enhance ROS accumulation, stimulate mitochondrial permeability transition pore (MPTP) opening, accelerate the loss of mitochondrial membrane potential (MMP) and promote cytochrome c release from mitochondria to the cytoplasm, which, as a result, effectively triggered three classical types of PCD pathways in mycelia of P. italicum.


Assuntos
Flavanonas , Penicillium , Potencial da Membrana Mitocondrial , Mitocôndrias , Proteômica
9.
Phys Rev Lett ; 120(26): 267601, 2018 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-30004731

RESUMO

Owing to the broken translational symmetry at dislocations, a strain gradient naturally exists around the dislocation cores and can significantly influence the electrical and mechanical properties. We use aberration corrected scanning transmission electron microscopy to directly measure the flexoelectric polarization (∼28 µC cm^{-2}) at dislocation cores in SrTiO_{3}. The polarization charges can interact with the nonstoichiometric dislocation cores and thus impact the electrical activities. Our findings can help us to understand the properties of dislocations in perovskite, providing new insights into the design of new devices via defect engineering such as bicrystal fabrication and thin film growth.

10.
J Am Chem Soc ; 139(44): 15592-15595, 2017 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-29058888

RESUMO

Directional growth of ultralong nanowires (NWs) is significant for practical application of large-scale optoelectronic integration. Here, we demonstrate the controlled growth of in-plane directional perovskite CsPbBr3 NWs, induced by graphoepitaxial effect on annealed M-plane sapphire substrates. The wires have a diameter of several hundred nanometers, with lengths up to several millimeters. Microstructure characterization shows that CsPbBr3 NWs are high-quality single crystals, with smooth surfaces and well-defined cross section. The NWs have very strong band-edge photoluminescence (PL) with a long PL lifetime of ∼25 ns and can realize high-quality optical waveguides. Photodetectors constructed on these individual NWs exhibit excellent photoresponse with an ultrahigh responsivity of 4400 A/W and a very fast response speed of 252 µs. This work presents an important step toward scalable growth of high-quality perovskite NWs, which will provide promising opportunities in constructing integrated nanophotonic and optoelectronic systems.

11.
J Ind Microbiol Biotechnol ; 43(10): 1481-95, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27538968

RESUMO

This study focused on the differences in protein expression at various periods during limonene biotransformation by Penicillium digitatum DSM 62840. A total of 3644 protein-species were quantified by iTRAQ during limonene biotransformation (0 and 12 h). A total of 643 proteins were differentially expressed, 316 proteins were significantly up-regulated and 327 proteins were markedly down-regulated. GO, COG, and pathway enrichment analysis showed that the differentially expressed proteins possessed catalytic and binding functions and were involved in a variety of cellular and metabolic process. Furthermore, the enzymes involved in limonene transformation might be related to cytochrome P-450. This study provided a powerful platform for further exploration of biotransformation, and the identified proteins provided insight into the mechanism of limonene transformation.


Assuntos
Cicloexenos/metabolismo , Proteínas Fúngicas/metabolismo , Penicillium/metabolismo , Terpenos/metabolismo , Biotransformação , Cromatografia Líquida , Cicloexenos/química , Limoneno , Proteômica , Espectrometria de Massas em Tandem , Terpenos/química
12.
J Sci Food Agric ; 96(6): 2136-41, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26140351

RESUMO

BACKGROUND: Botrytis cinerea and Rhizopus stolonifer, two main postharvest pathogens, cause great loss of strawberry fruits. Here, the effects of poplar buds extracts, a main plant source for Chinese propolis, on disease control were investigated in vitro and in vivo. RESULTS: The HPLC profile of poplar buds ethanol extract (PBEE) was almost identical to that of propolis ethanol extract (PEE), with the active flavonoids identified as pinocembrin, chrysin and galangin. PBEE exhibited similar inhibitory activities on spore germination of both pathogens compared with PEE, and PBEE also strongly inhibited the mycelial growth of the pathogens. In vivo, PBEE could effectively reduce decay of strawberry fruits stored at 13 °C. Although the weight loss was slightly increased, the contents of total soluble solid, titritable acid, vitamin C and total anthocyanins were significantly higher in PBEE treated fruits than those of the control. CONCLUSION: PBEE had the similar antifungal activity with propolis and had great potential as an alternative to propolis to control strawberry fruits diseases.


Assuntos
Flores/química , Fragaria/microbiologia , Frutas/química , Extratos Vegetais/farmacologia , Populus/química , Própole/química , Botrytis/efeitos dos fármacos , Relação Dose-Resposta a Droga , Conservantes de Alimentos/química , Conservantes de Alimentos/farmacologia , Extratos Vegetais/química , Rhizopus/efeitos dos fármacos , Esporos Fúngicos/efeitos dos fármacos
13.
Lipids Health Dis ; 13: 47, 2014 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-24621278

RESUMO

BACKGROUND: Studies investigating the association between the apolipoprotein E (APOE) gene polymorphism and the risk of intracerebral hemorrhage (ICH) have reported conflicting results. We here performed a meta-analysis based on the evidence currently available from the literature to make a more precise estimation of this relationship. METHODS: Published literature from the National Library of Medline and Embase databases were retrieved. Odds ratio (OR) and 95% confidence interval (CI) were calculated in fixed- or random-effects models when appropriate. Subgroup analyses were performed by race. RESULTS: This meta-analysis included 11 case-control studies, which included 1,238 ICH cases and 3,575 controls. The combined results based on all studies showed that ICH cases had a significantly higher frequency of APOE ϵ4 allele (OR= 1.42, 95% CI= 1.21,1.67, P<0.001). In the subgroup analysis by race, we also found that ICH cases had a significantly higher frequency of APOE ϵ4 allele in Asians (OR= 1.52, 95% CI= 1.20,1.93, P<0.001) and in Caucasians (OR= 1.34, 95% CI= 1.07,1.66, P=0.009). There was no significant relationship between APOE ϵ2 allele and the risk of ICH. CONCLUSION: Our meta-analysis suggested that APOE ϵ4 allele was associated with a higher risk of ICH.


Assuntos
Apolipoproteínas E/genética , Hemorragia Cerebral/genética , Estudos de Casos e Controles , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Polimorfismo Genético , Isoformas de Proteínas/genética , Fatores de Risco
14.
J Fungi (Basel) ; 10(6)2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38921355

RESUMO

Penicillium italicum, a major postharvest pathogen, causes blue mold rot in citrus fruits through the deployment of various virulence factors. Recent studies highlight the role of the epigenetic reader, SntB, in modulating the pathogenicity of phytopathogenic fungi. Our research revealed that the deletion of the SntB gene in P. italicum led to significant phenotypic alterations, including delayed mycelial growth, reduced spore production, and decreased utilization of sucrose. Additionally, the mutant strain exhibited increased sensitivity to pH fluctuations and elevated iron and calcium ion stress, culminating in reduced virulence on Gannan Novel oranges. Ultrastructural analyses disclosed notable disruptions in cell membrane integrity, disorganization within the cellular matrix, and signs of autophagy. Transcriptomic data further indicated a pronounced upregulation of hydrolytic enzymes, oxidoreductases, and transport proteins, suggesting a heightened energy demand. The observed phenomena were consistent with a carbon starvation response potentially triggering apoptotic pathways, including iron-dependent cell death. These findings collectively underscored the pivotal role of SntB in maintaining the pathogenic traits of P. italicum, proposing that targeting PiSntB could offer a new avenue for controlling citrus fungal infections and subsequent fruit decay.

15.
Chemosphere ; 353: 141533, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38403126

RESUMO

Ion precipitation flotation technology was demonstrated to be an efficient method for the separation of valuable metals from low-concentration solution. However, the selective separation of three metals from mixing solution is a great challenge, and highly selective reagents are the key to polymetallic separation. In this work, stepwise separation of Co and Zn from the simulated zinc hydrometallurgy wastewater containing ternary Co-Zn-Mn metals by ion precipitation flotation process was proposed. It's demonstrated that organic reagents of 1-nitroso-2-naphthol (NN) and sodium dimethyldithiocarbamate (SDDC) had excellent selectivity for the capture of Co and Zn to form respective precipitate from wastewaters via the chelation reactions. After precipitation, dodecylpyridinium chloride (DPC) and tetradecyltrimethylammonium bromide (TTAB) were chosen as surfactants for the separation of Co and Zn sediments from the solution via the flotation process. The effects of solution pH, molar ratio, reaction temperature, and reaction time on the selective precipitation efficiencies of Co and Zn as well as the effects of surfactant dosage and flotation gas velocity on the flotation separation efficiencies were systematically investigated. It's demonstrated that the comprehensive recovery rates of Co, Mn, and Zn reach 98%, 90%, and 99%, respectively. After separation, oxidation calcination of the foam products was conducted to prepare high-purity Co3O4 and ZnO nanoparticles in which the organic matters were burnt out with gas emissions. The stepwise chelation capture mechanisms of Co and Zn by highly selective precipitation reagents were minutely discussed. It's demonstrated that the proposed selective stepwise precipitation and flotation method is suitable for recovery of critical metal ions from low-concentration polymetallic wastewaters.


Assuntos
Águas Residuárias , Zinco , Metais , Indicadores e Reagentes , Tensoativos , Íons
16.
PLoS One ; 19(3): e0299298, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38547075

RESUMO

We here describe the external morphology and complete mitochondrial genome characteristics of Mecidea indica Dallas, 1851, and clarify the evolutionary rate and divergence time. The M. indica mitochondrial genome length is 15,670 bp, and it exhibits a typical high A+T-skew (76.31%). The sequence shows strong synteny with the original gene arrangement of Drosophila yakuba Burla, 1954 without rearrangement. The M. indica mitochondrial genome characteristics were analyzed, and phylogenetic trees of Pentatomidae were reconstructed using Bayesian methods based on different datasets of the mitochondrial genome datasets. Phylogenetic analysis shows that M. indica belongs to Pentaotominae and form a sister-group with Anaxilaus musgravei Gross, 1976, and Asopinae is highly supported as monophyletic. Molecular clock analysis estimates a divergence time of Pentatomidae of 122.75 Mya (95% HPD: 98.76-145.43 Mya), within the Mesozoic Cretaceous; the divergence time of M. indica and A. musgravii was no later than 50.50 Mya (95% HPD: 37.20-64.80 Mya). In addition, the divergence time of Asopinae was 62.32 Mya (95% HPD: 47.08-78.23 Mya), which was in the Paleogene of the Cenozoic era. This study is of great significance for reconstructing the phylogeny of Pentatomidae and providing insights into its evolutionary history.


Assuntos
Genoma Mitocondrial , Heterópteros , Animais , Filogenia , Teorema de Bayes , Heterópteros/genética , Evolução Biológica
17.
Sci Total Environ ; 930: 172755, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38670372

RESUMO

With the advancement of technology, wastewater treatment has become a significant challenge limiting the clean and sustainable development of chemical and metallurgical industries. Foam extraction, based on interfacial separation and mineral flotation, has garnered considerable attention as a wastewater treatment technology due to its unique physicochemical properties. Although considerable excellent accomplishments were reported, there still lacks a comprehensive summary of process features and contaminant removal mechanisms via foam extraction. According to the latest research progresses, the principles and characteristics of foam extraction technology, the classification and application of flotation reagents are systematically summarized in this work. Then comprehensively commented on the application fields and prospects of iterative flotation technology such as ion flotation, adsorption flotation and floating-extraction. The shortcomings and limitations of the current foam extraction technologies were discussed, and the feasible process intensification techniques were highlighted. This review aims to enchance the understanding of the foam extraction mechanism, and provides guidance for the selection appropriate reagents and foam extraction technologies in wastewater treatment.

18.
Nat Commun ; 14(1): 2864, 2023 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-37208365

RESUMO

Faithful chromosome segregation of 8 duplicated haploid genomes into 8 daughter gametes is essential for male gametogenesis and mosquito transmission of Plasmodium. Plasmodium undergoes endomitosis in this multinucleated cell division, which is highly reliant on proper spindle-kinetochore attachment. However, the mechanisms underlying the spindle-kinetochore attachment remain elusive. End-binding proteins (EBs) are conserved microtubule (MT) plus-end binding proteins and play an important role in regulating MT plus-end dynamics. Here, we report that the Plasmodium EB1 is an orthologue distinct from the canonical eukaryotic EB1. Both in vitro and in vivo assays reveal that the Plasmodium EB1 losses MT plus-end tracking but possesses MT-lattice affinity. This MT-binding feature of Plasmodium EB1 is contributed by both CH domain and linker region. EB1-deficient parasites produce male gametocytes that develop to the anucleated male gametes, leading to defective mosquito transmission. EB1 is localized at the nucleoplasm of male gametocytes. During the gametogenesis, EB1 decorates the full-length of spindle MTs and regulates spindle structure. The kinetochores attach to spindle MTs laterally throughout endomitosis and this attachment is EB1-dependent. Consequently, impaired spindle-kinetochore attachment is observed in EB1-deficient parasites. These results indicate that a parasite-specific EB1 with MT-lattice binding affinity fulfills the spindle-kinetochore lateral attachment in male gametogenesis.


Assuntos
Proteínas Associadas aos Microtúbulos , Plasmodium , Segregação de Cromossomos , Cinetocoros/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Mitose , Plasmodium/genética , Fuso Acromático/metabolismo
19.
Zookeys ; 1185: 143-161, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38074901

RESUMO

The hedgehog genus Mesechinus (Erinaceidae, Eulipotyphla) is currently comprised of four species, M.dauuricus, M.hughi, M.miodon, and M.wangi. Except for M.wangi, which is found in southwestern China, the other three species are mainly distributed in northern China and adjacent Mongolia and Russia. From 2018 to 2023, we collected seven Mesechinus specimens from Anhui and Zhejiang provinces, eastern China. Here, we evaluate the taxonomic and phylogenetic status of these specimens by integrating molecular, morphometric, and karyotypic approaches. Our results indicate that the Anhui and Zhejiang specimens are distinct from the four previously recognized species and are a new species. We formally described it here as Mesechinusorientalissp. nov. It is the only Mesechinus species occurring in eastern China and is geographically distant from all known congeners. Morphologically, the new species is most similar to M.hughi, but it is distinguishable from that species by the combination of its smaller size, shorter spines, and several cranial characteristics. Mesechinusorientalis sp. nov. is a sister to the lineage composed of M.hughi and M.wangi from which it diverged approximately 1.10 Ma.

20.
Biochem Biophys Res Commun ; 422(2): 233-7, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22575447

RESUMO

Light state transition in oxygenic organisms was defined as the ability to equalize the excitation of the two photosystems for maximal photosynthetic efficiency. In cyanobacteria, extensive researches on state transition have continuously provided new knowledge in the past decades but the molecular mechanism and physiological significance are still ambiguous. In this work, kinetics and dynamics of the transition from state 1 to state 2 in cyanobacterium Spirulina platensis cells were studied at different intensity of orange light from 10 to 120 µmol m(-2) s(-1). It was revealed that the state transition worked constantly independent of light intensity while the rates varied. The synchronous fluorescence kinetics for phycobilisome (PBS) and photosystem components indicated that the state transition was entirely regulated by "mobile PBS", and continuously changed fluorescence amplitudes suggested a series of intermediate states were involved between state 1 and state 2. The dynamic property of PBS movement during the state transition was revealed by (1,0) distribution of photo-linkable PBSs, indicating a collective movement of all PBSs. The results suggest that state transition in cyanobacteria possesses not only physiological but also photochemical significance.


Assuntos
Luz , Fotossíntese , Ficobilissomas/fisiologia , Spirulina/fisiologia , Fluorescência , Cinética , Ficobilissomas/efeitos da radiação , Spirulina/efeitos da radiação , Spirulina/ultraestrutura
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