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1.
Arch Virol ; 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34608523

RESUMO

Internal ribosome entry site (IRES)-dependent translation is a mechanism distinct from 5' cap-dependent translation. IRES elements are located mainly in the 5' untranslated regions (UTRs) of viral and eukaryotic mRNAs. However, IRESs are also found in the coding regions of some viral and eukaryotic genomes to initiate the translation of some functional truncated isoforms. Here, five putative IRES elements of human rhinovirus 16 (HRV16) were identified in the coding region of the nonstructural proteins P2 and P3 through fusion with green fluorescent protein (GFP) expression vectors and bicistronic vectors with a hairpin structure. These five putative IRESs were located at nucleotide positions 4286-4585, 5002-5126, 6245-6394, 6619-6718, and 6629-6778 in the HRV16 genome. The functionality of the five IRESs was confirmed by their ability to initiate GFP expression in vitro. This suggests that an alternative mechanism might be used to increase the efficiency of replication of HRV16.

2.
BMC Plant Biol ; 21(1): 376, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34399701

RESUMO

BACKGROUND: Glycolytic pathway is common in all plant organs, especially in oxygen-deficient tissues. Phosphofructokinase (PFK) is a rate-limiting enzyme in the glycolytic pathway and catalyses the phosphorylation of fructose-6-phosphate to fructose-1,6-bisphosphate. Cassava (M. esculenta) root is a huge storage organ with low amount of oxygen. However, less is known about the functions of PFK from M. esculenta (MePFK). We conducted a systematic analysis of MePFK genes to explore the function of the MePFK gene family under hypoxic stress. RESULTS: We identified 13 MePFK genes and characterised their sequence structure. The phylogenetic tree divided the 13 genes into two groups: nine were MePFKs and four were pyrophosphate-fructose-6-phosphate phosphotransferase (MePFPs). We confirmed by green fluorescent protein fusion protein expression that MePFK03 and MePFPA1 were localised in the chloroplast and cytoplasm, respectively. The expression profiles of the 13 MePFKs detected by quantitative reverse transcription polymerase chain reaction revealed that MePFK02, MePFK03, MePFPA1, MePFPB1 displayed higher expression in leaves, root and flower. The expression of MePFK03, MePFPA1 and MePFPB1 in tuber root increased gradually with plant growth. We confirmed that hypoxia occurred in the cassava root, and the concentration of oxygen was sharply decreasing from the outside to the inside root. The expression of MePFK03, MePFPA1 and MePFPB1 decreased with the decrease in the oxygen concentration in cassava root. Waterlogging stress treatment showed that the transcript level of PPi-dependent MePFP and MeSuSy were up-regulated remarkably and PPi-dependent glycolysis bypass was promoted. CONCLUSION: A systematic survey of phylogenetic relation, molecular characterisation, chromosomal and subcellular localisation and cis-element prediction of MePFKs were performed in cassava. The expression profiles of MePFKs in different development stages, organs and under waterlogging stress showed that MePFPA1 plays an important role during the growth and development of cassava. Combined with the transcriptional level of MeSuSy, we found that pyrophosphate (PPi)-dependent glycolysis bypass was promoted when cassava was under waterlogging stress. The results would provide insights for further studying the function of MePFKs under hypoxic stress.


Assuntos
Genoma de Planta , Manihot/enzimologia , Manihot/genética , Fosfofrutoquinases/genética , Fosfofrutoquinases/metabolismo , Cloroplastos/enzimologia , Mapeamento Cromossômico , Cromossomos de Plantas , Sequência Conservada , Citoplasma/enzimologia , Éxons , Flores/enzimologia , Íntrons , Família Multigênica , Oxigênio/metabolismo , Filogenia , Folhas de Planta/enzimologia , Raízes de Plantas/enzimologia , Regiões Promotoras Genéticas , Estresse Fisiológico/genética , Transcriptoma
3.
Sci Total Environ ; 765: 144435, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33418329

RESUMO

The quagga mussel (Dreissena rostriformis bugensis) is a filter-feeding invasive species that has re-engineered many freshwater ecosystems worldwide. High clearance rates (CRs) and dense populations underpin their ecological impacts. CRs, however, are highly variable, as are environmental factors that regulate them. Despite their widespread distribution in Europe and North America, knowledge of how multiple environmental factors regulate CRs of quagga mussels remains limited. We investigated quagga mussel CRs under varying conditions including water temperature, food availability, habitat depth, flow velocity, and duration of incubation in chambers with both static and flowing water. We found that CR was positively related to water temperature and initial food concentration in static chambers. When coupled with limited food concentration, cold water (7.5 °C), due to a deep-water upwelling event, produced very low CR (~ 10× lower) compared to warmer water (12-24 °C) (0.47 vs. 3.12-5.84 L g-1 DW h-1). Mussels from deeper water (20 m) had CRs that were ~ 3.5× higher than from shallower depths (2-10 m) and CRs were inversely affected by total mussel dry weight. Flow rates from 1 to 22 cm s-1 generated a unimodal pattern of CR with an optimal flow velocity of 6-12 cm s-1 (~ 2× higher than suboptimal CRs). Enhanced flow velocity (22 cm s-1), reflective of storm conditions in shallow waters, significantly increased the closing/reopening activity of mussel valves relative to lower velocities (1-12 cm s-1). Incubation time had a strong negative effect (~ 2-4× reduction) on CRs likely reflecting refiltration in static chambers versus food saturation of mussels in flowing chambers, respectively. Our findings highlight how multiple factors can influence quagga mussel CRs by factors of 2-10. Given widespread habitat heterogeneity in large aquatic ecosystems, whole-lake estimates of mussel impacts should include multiple regulatory factors that affect mussel filtration.


Assuntos
Bivalves , Dreissena , Animais , Ecossistema , Europa (Continente) , Lagos , América do Norte
4.
Hortic Res ; 8(1): 14, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33419990

RESUMO

Passion fruit (Passiflora edulis Sims) is an economically valuable fruit that is cultivated in tropical and subtropical regions of the world. Here, we report an ~1341.7 Mb chromosome-scale genome assembly of passion fruit, with 98.91% (~1327.18 Mb) of the assembly assigned to nine pseudochromosomes. The genome includes 23,171 protein-coding genes, and most of the assembled sequences are repetitive sequences, with long-terminal repeats (LTRs) being the most abundant. Phylogenetic analysis revealed that passion fruit diverged after Brassicaceae and before Euphorbiaceae. Ks analysis showed that two whole-genome duplication events occurred in passion fruit at 65 MYA and 12 MYA, which may have contributed to its large genome size. An integrated analysis of genomic, transcriptomic, and metabolomic data showed that 'alpha-linolenic acid metabolism', 'metabolic pathways', and 'secondary metabolic pathways' were the main pathways involved in the synthesis of important volatile organic compounds (VOCs) in passion fruit, and this analysis identified some candidate genes, including GDP-fucose Transporter 1-like, Tetratricopeptide repeat protein 33, protein NETWORKED 4B isoform X1, and Golgin Subfamily A member 6-like protein 22. In addition, we identified 13 important gene families in fatty acid pathways and eight important gene families in terpene pathways. Gene family analysis showed that the ACX, ADH, ALDH, and HPL gene families, especially ACX13/14/15/20, ADH13/26/33, ALDH1/4/21, and HPL4/6, were the key genes for ester synthesis, while the TPS gene family, especially PeTPS2/3/4/24, was the key gene family for terpene synthesis. This work provides insights into genome evolution and flavor trait biology and offers valuable resources for the improved cultivation of passion fruit.

5.
FASEB J ; 35(2): e20995, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32910509

RESUMO

Virus entry into cells is the initial stage of infection and involves multiple steps, and interfering viral entry represents potential antiviral approaches. Ion channels are pore-forming membrane proteins controlling cellular ion homeostasis and regulating many physiological processes, but their roles during viral infection have rarely been explored. Here, the functional Kv1.3 ion channel was found to be expressed in human hepatic cells and tissues. The Kv1.3 was then revealed to restrict HCV entry via inhibiting endosome acidification-mediated viral membrane fusion. The Kv1.3 was also demonstrated to inhibit DENV and ZIKV with an endosome acidification-dependent entry, but have no effect on SeV with a neutral pH penetration. A Kv1.3 antagonist PAP-1 treatment accelerated animal death in ZIKV-infected Ifnar1-/- mice. Moreover, Kv1.3-deletion was found to promote weight loss and reduce survival rate in ZIKV-infected Kv1.3-/- mice. Altogether, the Kv1.3 ion channel behaves as a host factor restricting viral entry. These findings broaden understanding about ion channel biology.


Assuntos
Vírus da Dengue/fisiologia , Dengue/metabolismo , Hepacivirus/fisiologia , Hepatite C/metabolismo , Canal de Potássio Kv1.3/metabolismo , Infecções por Respirovirus/metabolismo , Vírus Sendai/fisiologia , Internalização do Vírus , Infecção por Zika virus/metabolismo , Zika virus/fisiologia , Animais , Chlorocebus aethiops , Dengue/virologia , Endossomos/metabolismo , Ficusina/farmacologia , Células HEK293 , Hepatite C/virologia , Humanos , Concentração de Íons de Hidrogênio , Canal de Potássio Kv1.3/antagonistas & inibidores , Canal de Potássio Kv1.3/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infecções por Respirovirus/virologia , Transfecção , Células Vero , Internalização do Vírus/efeitos dos fármacos , Infecção por Zika virus/virologia
6.
Antiviral Res ; 182: 104922, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32858116

RESUMO

Arboviruses, especially Dengue virus (DENV) and Zika virus (ZIKV), have been a severe threat to human health in the last few years due to uncontrollable transmission. There are no approved vaccines or clinical drugs available for use to prevent and treat their infections. Transient receptor potential mucolipin 2 and 3 (TRPML2 and TRPML3) were reported to modulate viral entry, but the antiviral function of these modulators was unknown. Here, we reported that ML-SA1, a TRPML agonist, inhibited DENV2 and ZIKV in vitro in a dose-dependent manner. Time-of-drug-addition experiments showed that ML-SA1 mainly restricted viral entry. Moreover, the selective TRPML3 activator SN-2 was found to share a similar antiviral effect against DENV2 and ZIKV, but the specific TRPML1 agonist MK6-83 was not effective. Although ML-SA1 was further revealed to induce autophagy, its antiviral role was independent of autophagy induction. Finally, ML-SA1 was found to inhibit DENV2 and ZIKV by promoting lysosome acidification and protease activity to cause viral degradation. Together, our study identifies two TRPML agonists, ML-SA1 and SN-2, as potent inhibitors of DENV2 and ZIKV, which may lead to the discovery of new candidates against viruses.

7.
Front Genet ; 11: 238, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32292416

RESUMO

Rheumatoid arthritis (RA) is a common autoimmune disorder influenced by both genetic and environmental factors. To investigate possible contributions of DNA methylation to the etiology of RA with minimum confounding genetic heterogeneity, we investigated genome-wide DNA methylation in disease-discordant monozygotic twin pairs. This study hypothesized that methylomic biomarkers might facilitate accurate RA detection. A comprehensive series of biomarker detection algorithms were utilized to find the best methylomic biomarkers for detecting RA patients using the methylomic data of the peripheral blood samples. The best model achieved 100.00% in accuracy (Acc) with 81 methylomic biomarkers and a 10-fold cross-validation (10FCV) strategy. Some of the methylomic biomarkers were experimentally confirmed to be associated with the onset or development of RA. It is also interesting to observe that many of the detected biomarkers were from chromosome Y, supporting the knowledge that RA has a significant gender discrepancy.

8.
Viruses ; 12(3)2020 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-32182730

RESUMO

Interferon-inducible transmembrane proteins (IFITM1/2/3) have been reported to suppress the entry of a wide range of viruses. However, their antiviral functional residues and specific mechanisms are still unclear. Here, we firstly resolved the topology of IFITM1 on the plasma membrane where N-terminus points into the cytoplasm and C-terminus resides extracellularly. Further, KRRK basic residues of IFITM1 locating at 62-67 of the conserved intracellular loop (CIL) were found to play a key role in the restriction on the Zika virus (ZIKV) and dengue virus (DENV). Similarly, KRRK basic residues of IFITM2/3 also contributed to suppressing ZIKV replication. Finally, IFITM1 was revealed to be capable of restricting the release of ZIKV particles from endosome to cytosol so as to impede the entry of ZIKV into host cells, which was tightly related with the inhibition of IFITM1 on the acidification of organelles. Overall, our study provided topology, antiviral functional residues and the mechanism of interferon-inducible transmembrane proteins.


Assuntos
Antígenos de Diferenciação/metabolismo , Antígenos de Diferenciação/farmacologia , Antivirais/metabolismo , Antivirais/farmacologia , Zika virus/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Membrana Celular/metabolismo , Chlorocebus aethiops , Endossomos/metabolismo , Células HEK293 , Humanos , Interferons/metabolismo , Proteínas de Membrana/metabolismo , Alinhamento de Sequência , Células Vero , Replicação Viral/efeitos dos fármacos , Infecção por Zika virus
9.
Sci Total Environ ; 711: 134679, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31810685

RESUMO

Filter feeding activities link suspension feeders with their environment and underpin their impact on aquatic ecosystems. Despite their ecological and economic impacts, the functional response and size-selective capture of suspended particulates have not been well documented for the golden mussel Limnoperna fortunei. Here we demonstrated that golden mussels had a type I functional response, with an attack rate a = 0.085 and negligible handling time (h). Clearance rate ranged between 72.6 ± 27.0 and 305.5 ± 105.9 mL ind.-1h-1 (Mean ± S.E.), depending on food concentrations, which exhibited an inverse relationship with clearance rate. Presence of golden mussels suppressed chlorophyll a concentration in experimental mesocosms, the extent of which was dependent on mussel abundance. Concentration of suspended particles in experimental mesocosms experienced a sharp initial decline across all size categories (≤1->50 µm), though with increased final concentration of large particles (>25 µm), indicating packaging and egestion by golden mussels of fine particles (down to ≤1 µm). Capture efficiency of quantitatively-dominant suspended matter (≤1-50 µm) by golden mussels was inversely related to particle size. Animal abundance, particle size, and their interaction (abundance × particle size) determined the extent to which matter was removed from the water column. Presently L. fortunei occurs primarily in the southern end of the central route of South to North Water Diversion Project (China), but the species is spreading north; we anticipate that impacts associated with filtering of L. fortunei will correspond with local population abundance along this gradient.


Assuntos
Mytilidae , Animais , China , Clorofila A , Ecossistema , Água Doce
10.
Environ Pollut ; 252(Pt B): 1659-1670, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31284208

RESUMO

The Yangtze River, which is the largest in Euro-Asian, receives tremendous anthropogenic nitrogen input and is typically characterized by severe eutrophication and hypoxia. Two major processes, denitrification and anaerobic ammonium oxidation (anammox), play vital roles for removing nitrogen global in nitrogen cycling. In the current study, sediment samples were collected from both latitudinal and longitudinal transects along the coastal Yangtze River and the East China Sea (ECS). We investigated community composition and distributions of nosZ gene-encoded denitrifiers by high throughput sequencing, and also quantified the relative abundances of both denitrifying and anammox bacteria by q-PCR analysis. Denitrifying communities showed distinct spatial distribution patterns that were impacted by physical (water current and river runoffs) and chemical (nutrient availability and organic content) processes. Both denitrifying and anammox bacteria contributed to the nitrogen removal in Yangtze Estuary and the adjacent ECS, and these two processes shifted from coastal to open ocean with reverse trends: the abundance of nosZ gene decreased from coastal to open ocean while anammox exhibited an increasing trend based on quantifications of hzsB and 16S rRNA genes. Further correspondence correlation analysis revealed that salinity and nutrients were the main factors in structuring composition and distribution of denitrifying and anammox bacteria. This study improved our understanding of dynamic processes in nitrogen removal from estuarine to open ocean. We hypothesize that denitrification is the major nitrogen removal pathway in estuaries, but in open oceans, low nutrient and organic matter concentrations restrict denitrification, thus increasing the importance of anammox as a nitrogen removal process.


Assuntos
Amônia/metabolismo , Estuários , Ciclo do Nitrogênio , Nitrogênio/metabolismo , Rios/microbiologia , Água do Mar/microbiologia , China , Desnitrificação , Genes Bacterianos , Ciclo do Nitrogênio/genética , Oceanos e Mares , Oxirredução , Rios/química , Salinidade , Água do Mar/química
11.
Genome ; 62(8): 563-569, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31158327

RESUMO

Heat shock transcription factors (Hsfs) are important regulators of biotic and abiotic stress responses in plants. Currently, the Hsf gene family is not well understood in cassava, an important tropical crop. In the present study, 32 MeHsf genes were identified from the cassava genome database, which were divided into three types based on functional domain and motif distribution analyses. Analysis of the differential expression of the genes belonging to the Hsf family in cassava was carried out based on published cassava transcriptome data from tissues/organs (leaf blade, leaf midvein, lateral buds, organized embryogenic structures, friable embryogenic callus, fibrous roots, storage roots, stem, petiole, shoot apical meristem, and root apical meristem) under abiotic stress (cold, drought) or biotic stress (mealybugs. cassava brown streak disease, cassava bacterial blight). The results show the expression diversity of cassava Hsfs genes in various tissues/organs. The transcript levels of MeHsfB3a, MeHsfA6a, MeHsfA2a, and MeHsfA9b were upregulated by abiotic and biotic stresses, such as cold, drought, cassava bacterial blight, cassava brown streak disease, and mealybugs, indicating their potential roles in mediating the response of cassava plants to environment stresses. Further interaction network and co-expression analyses suggests that Hsf genes may interact with Hsp70 family members to resist environmental stresses in cassava. These results provide valuable information for future studies of the functional characterization of the MeHsf gene family.


Assuntos
Resposta ao Choque Frio , Proteínas de Choque Térmico/genética , Manihot/genética , Proteínas de Plantas/genética , Transcriptoma , Secas , Regulação da Expressão Gênica de Plantas , Proteínas de Choque Térmico/metabolismo , Manihot/microbiologia , Manihot/parasitologia , Proteínas de Plantas/metabolismo
12.
Sci Rep ; 9(1): 3834, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30846860

RESUMO

Stylosanthes guianensis (Aubl.) Sw. is an economically important pasture and forage legume in tropical regions of the world. Genetic improvement of the crop can be enhanced through marker-assisted breeding. However, neither single nucleotide polymorphism (SNP) markers nor SNP-based genetic linkage map has been previously reported. In this study, a high-quality genetic linkage map of 2572 SNP markers for S. guianensis is generated using amplified-fragment single nucleotide polymorphism and methylation (AFSM) approach. The genetic map has 10 linkage groups (LGs), which spanned 2226.6 cM, with an average genetic distance of 0.87 cM between adjacent markers. Genetic mapping of quantitative trait loci (QTLs) for important agronomic traits such as yield-related and nutritional or quality-related traits was performed using F2 progeny of a cross between a male-sterile female parent TPRC1979 and male parent TPRCR273 with contrasting phenotypes for morphological and physiological traits. A total of 30 QTLs for 8 yield-related traits and 18 QTLs for 4 nutritional or quality-related traits are mapped on the linkage map. Both the high-quality genetic linkage map and the QTL mapping for important agronomic traits described here will provide valuable genetic resources for marker-assisted selection for S. guianensis.


Assuntos
Mapeamento Cromossômico , Produtos Agrícolas/genética , Fabaceae/genética , Locos de Características Quantitativas/genética , Mapeamento Cromossômico/métodos , Produção Agrícola , DNA de Plantas/genética , Fabaceae/crescimento & desenvolvimento , Polimorfismo de Nucleotídeo Único/genética , Análise de Sequência de DNA
13.
J Biol Chem ; 294(1): 182-194, 2019 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-30404919

RESUMO

Viral infections still threaten human health all over the world, and many people die from viral diseases every year. However, there are no effective vaccines or drugs for preventing or managing most viral diseases. Thus, the discovery and development of broad-spectrum antiviral agents remain urgent. Here, we expressed and purified a venom peptide, Ev37, from the scorpion Euscorpiops validus in a prokaryotic system. We found that rEv37 can inhibit dengue virus type 2 (DENV-2), hepatitis C virus (HCV), Zika virus (ZIKV), and herpes simplex virus type 1 (HSV-1) infections in a dose-dependent manner at noncytotoxic concentrations, but that it has no effect on Sendai virus (SeV) and adenovirus (AdV) infections in vitro Furthermore, rEv37 alkalized acidic organelles to prevent low pH-dependent fusion of the viral membrane-endosomal membrane, which mainly blocks the release of the viral genome from the endosome to the cytoplasm and then restricts viral late entry. Taken together, our results indicate that the scorpion venom peptide Ev37 is a broad-spectrum antiviral agent with a specific molecular mechanism against viruses undergoing low pH-dependent fusion activation during entry into host cells. We conclude that Ev37 is a potential candidate for development as an antiviral drug.


Assuntos
Citoplasma/metabolismo , Vírus da Dengue/fisiologia , Endossomos/metabolismo , Venenos de Escorpião/farmacologia , Escorpiões/química , Internalização do Vírus/efeitos dos fármacos , Adenoviridae/fisiologia , Animais , Chlorocebus aethiops , Citoplasma/virologia , Endossomos/virologia , Células HEK293 , Humanos , Fusão de Membrana/efeitos dos fármacos , Venenos de Escorpião/química , Vírus Sendai/fisiologia , Células Vero
14.
Sci Total Environ ; 646: 1367-1375, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30235622

RESUMO

Biofouling by the invasive mussel species Limnoperna fortunei has caused severe negative consequences in various freshwater ecosystems, but there is still a lack of effective antifouling strategies for this species, particularly in drinking water treatment systems where many existing strategies cannot be used. Chemical oxidants have been proposed to potentially control fouling mussels by influencing 3,4­dihydroxyphenylalanine oxidation involved in byssus adhesion. To test this potential control strategy, L. fortunei adults were exposed to four oxidants: sodium hypochlorite (NaClO), potassium permanganate (KMnO4), hydrogen peroxide (H2O2) and chloramine T (CAT) at concentrations of 0.5, 1.0, 3.0 and 5.0 mg L-1 for one week. The results showed that low concentrations of KMnO4 stimulated foot protein secretion, which was beneficial to byssus production (number and length). NaClO and H2O2, but not KMnO4 and CAT, significantly inhibited byssus production and reduced breaking force, causing an increased byssus shedding rate. However, only NaClO dissolved byssus and altered the failure location from the byssal thread to adhesive plaque, even when exposed at low concentrations, showing its great impacts on byssus adhesion. Further analysis of polyphenoloxidase activities and gene expression profiles of LfBP-1, LfFP-2 and LfBP-3 revealed that chemical oxidants affected byssus adhesion by altering Dopa oxidation and foot protein gene expressions. This study, therefore, suggests that a low concentration of NaClO can be used as an alternative and environmentally friendly chemical for controlling L. fortunei biofouling by weakening byssus adhesion.


Assuntos
Incrustação Biológica/prevenção & controle , Bivalves/fisiologia , Oxidantes/química , Animais , Água Doce , Peróxido de Hidrogênio , Navios
15.
Virol Sin ; 33(6): 545-556, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30569290

RESUMO

Dengue virus (DENV) and Zika virus (ZIKV) have spread throughout many countries in the developing world and infect millions of people every year, causing severe harm to human health and the economy. Unfortunately, there are few effective vaccines and therapies available against these viruses. Therefore, the discovery of new antiviral agents is critical. Herein, a scorpion venom peptide (Smp76) characterized from Scorpio maurus palmatus was successfully expressed and purified in Escherichia coli BL21(DE3). The recombinant Smp76 (rSmp76) was found to effectively inhibit DENV and ZIKV infections in a dose-dependent manner in both cultured cell lines and primary mouse macrophages. Interestingly, rSmp76 did not inactivate the viral particles directly but suppressed the established viral infection, similar to the effect of interferon (IFN)-ß. Mechanistically, rSmp76 was revealed to upregulate the expression of IFN-ß by activating interferon regulatory transcription factor 3 (IRF3) phosphorylation, enhancing the type-I IFN response and inhibiting viral infection. This mechanism is significantly different from traditional virucidal antimicrobial peptides (AMPs). Overall, the scorpion venom peptide Smp76 is a potential new antiviral agent with a unique mechanism involving type-I IFN responses, demonstrating that natural AMPs can enhance immunity by functioning as immunomodulators.


Assuntos
Antivirais/farmacologia , Interferon Tipo I/imunologia , Peptídeos/farmacologia , Venenos de Escorpião/farmacologia , Animais , Linhagem Celular , Vírus da Dengue/efeitos dos fármacos , Escherichia coli/genética , Regulação da Expressão Gênica , Humanos , Fator Regulador 3 de Interferon/imunologia , Interferon beta/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/virologia , Camundongos , Proteínas Recombinantes/farmacologia , Zika virus/efeitos dos fármacos
16.
Int J Mol Sci ; 19(9)2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30235813

RESUMO

ADP-glucose pyrophosphorylase (AGPase) is an important enzyme in the starch synthesis pathway. Its enzyme activity can determine the efficiency of starch biosynthesis. Cassava (Manihot esculenta Crantz) is the main staple crop worldwide and has a high starch content in its storage root. However, the inner regulatory mechanism of AGPase gene family is unclear. MePHD1; a plant homeodomain transcription factor; was isolated through a yeast one-hybrid screening using the promoter of ADP-glucose pyrophosphorylase small subunit1a (MeAGPS1a) as bait, and cassava storage root cDNA library as prey. This factor could bind to the MeAGPS1a promoter in vitro and in vivo, and its predicted binding region ranged from -400 bp to -201 bp, at the translation initiation site. The transcript level of MePHD1 could be induced by five plant hormones, and a temperature of 42 °C. This was down-regulated during the maturation process of the storage root. MePHD1 protein could repress the promoter activity of MeAGPS1a gene by a dual-luciferase assay; which indicated that MePHD1 is a negative regulator for the transcript level of MeAGPS1a gene.


Assuntos
Glucose-1-Fosfato Adenililtransferase/metabolismo , Proteínas de Homeodomínio/metabolismo , Manihot/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Regulação para Baixo , Regulação da Expressão Gênica de Plantas , Glucose-1-Fosfato Adenililtransferase/genética , Manihot/metabolismo , Proteínas de Plantas/genética , Regiões Promotoras Genéticas , Ligação Proteica
17.
Plant Cell Rep ; 37(12): 1611-1624, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30099610

RESUMO

KEY MESSAGE: The dynamic alterations of the physiological and molecular processes in reproductive stage soybean indicated the dramatic impact caused by drought. Drought is a major abiotic stress that limits soybean (Glycine max) production. Most prior studies were focused on either model species or crops that are at their vegetative stages. It is known that the reproductive stage of soybean is more susceptible to drought. Therefore, an understanding on the responsive mechanisms during this stage will not only be important for basic plant physiology, but the knowledge can also be used for crop improvement via either genetic engineering or molecular breeding. In this study, physiological measurements and RNA-Seq analysis were used to dissect the metabolic alterations and molecular responses in the leaves of soybean grown at drought condition. Photosynthesis rate, stomata conductance, transpiration, and water potential were reduced. The activities of SOD and CAT were increased, while the activity of POD stayed unchanged. A total of 2771 annotated genes with at least twofold changes were found to be differentially expressed in the drought-stressed plants in which 1798 genes were upregulated and 973 were downregulated. Via KEGG analysis, these genes were assigned to multiple molecular pathways, including ABA biogenesis, compatible compound accumulation, secondary metabolite synthesis, fatty acid desaturation, plant transcription factors, etc. The large number of differentially expressed genes and the diverse pathways indicated that soybean employs complicated mechanisms to cope with drought. Some of the identified genes and pathways can be used as targets for genetic engineering or molecular breeding to improve drought resistance in soybean.


Assuntos
Secas , Soja/genética , Soja/fisiologia , Estresse Fisiológico/genética , Transcriptoma/genética , Antioxidantes/metabolismo , Vias Biossintéticas/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Temperatura Alta , Folhas de Planta/genética , Folhas de Planta/fisiologia , Reprodução/genética
18.
Front Plant Sci ; 9: 503, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29725343

RESUMO

Cassava (Manihot esculenta Crantz) is a major tuberous crop produced worldwide. In this study, we sequenced 158 diverse cassava varieties and identified 349,827 single-nucleotide polymorphisms (SNPs) and indels. In each chromosome, the number of SNPs and the physical length of the respective chromosome were in agreement. Population structure analysis indicated that this panel can be divided into three subgroups. Genetic diversity analysis indicated that the average nucleotide diversity of the panel was 1.21 × 10-4 for all sampled landraces. This average nucleotide diversity was 1.97 × 10-4, 1.01 × 10-4, and 1.89 × 10-4 for subgroups 1, 2, and 3, respectively. Genome-wide linkage disequilibrium (LD) analysis demonstrated that the average LD was about ∼8 kb. We evaluated 158 cassava varieties under 11 different environments. Finally, we identified 36 loci that were related to 11 agronomic traits by genome-wide association analyses. Four loci were associated with two traits, and 62 candidate genes were identified in the peak SNP sites. We found that 40 of these genes showed different expression profiles in different tissues. Of the candidate genes related to storage roots, Manes.13G023300, Manes.16G000800, Manes.02G154700, Manes.02G192500, and Manes.09G099100 had higher expression levels in storage roots than in leaf and stem; on the other hand, of the candidate genes related to leaves, Manes.05G164500, Manes.05G164600, Manes.04G057300, Manes.01G202000, and Manes.03G186500 had higher expression levels in leaves than in storage roots and stem. This study provides basis for research on genetics and the genetic improvement of cassava.

19.
Front Physiol ; 9: 418, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29713291

RESUMO

Biofouling mediated by byssus adhesion in invasive bivalves has become a global environmental problem in aquatic ecosystems, resulting in negative ecological and economic consequences. Previous studies suggested that mechanisms responsible for byssus adhesion largely vary among bivalves, but it is poorly understood in freshwater species. Understanding of byssus structure and protein composition is the prerequisite for revealing these mechanisms. Here, we used multiple methods, including scanning electron microscope, liquid chromatography-tandem mass spectrometry, transcriptome sequencing, real-time quantitative PCR, inductively coupled plasma mass spectrometry, to investigate structure, and protein composition of byssus in the highly invasive freshwater mussel Limnoperna fortunei. The results indicated that the structure characteristics of adhesive plaque, proximal and distal threads were conducive to byssus adhesion, contributing to the high biofouling capacity of this species. The 3,4-dihydroxyphenyl-α-alanine (Dopa) is a major post-transnationally modification in L. fortunei byssus. We identified 16 representative foot proteins with typical repetitive motifs and conserved domains by integrating transcriptomic and proteomic approaches. In these proteins, Lfbp-1, Lffp-2, and Lfbp-3 were specially located in foot tissue and highly expressed in the rapid byssus formation period, suggesting the involvement of these foot proteins in byssus production and adhesion. Multiple metal irons, including Ca2+, Mg2+, Zn2+, Al3+, and Fe3+, were abundant in both foot tissue and byssal thread. The heavy metals in these irons may be directly accumulated by L. fortunei from surrounding environments. Nevertheless, some metal ions (e.g., Ca2+) corresponded well with amino acid preferences of L. fortunei foot proteins, suggesting functional roles of these metal ions by interacting with foot proteins in byssus adhesion. Overall, this study provides structural and molecular bases of adhesive mechanisms of byssus in L. fortunei, and findings here are expected to develop strategies against biofouling by freshwater organisms.

20.
Genes (Basel) ; 9(4)2018 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-29671773

RESUMO

Calcium (Ca2+) plays a crucial role in plant development and responses to environmental stimuli. Currently, calmodulins (CaMs), calmodulin-like proteins (CMLs), and calcineurin B-like proteins (CBLs), such as Ca2+ sensors, are not well understood in cassava (Manihotesculenta Crantz), an important tropical crop. In the present study, 8 CaMs, 48 CMLs, and 9 CBLs were genome-wide identified in cassava, which were divided into two, four, and four groups, respectively, based on evolutionary relationship, protein motif, and gene structure analyses. Transcriptomic analysis revealed the expression diversity of cassava CaMs-CMLs-CBLs in distinct tissues and in response to drought stress in different genotypes. Generally, cassava CaMs-CMLs-CBLs showed different expression profiles between cultivated varieties (Arg7 and SC124) and wild ancestor (W14) after drought treatment. In addition, numerous CaMs-CMLs-CBLs were significantly upregulated at 6 h, 12 h, and 48 h after harvest, suggesting their possible role during storage roots (SR) deterioration. Further interaction network and co-expression analyses suggested that a CBL-mediated interaction network was widely involved in SR deterioration. Taken together, this study provides new insights into CaMs-CMLs-CBLs-mediated drought adaption and SR deterioration at the transcription level in cassava, and identifies some candidates for the genetic improvement of cassava.

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