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1.
Microb Ecol ; 87(1): 76, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38801423

RESUMO

Modern crop production relies on the application of chemical pesticides and fertilizers causing environmental and economic challenges. In response, less environmentally impactful alternatives have emerged such as the use of beneficial microorganisms. These microorganisms, particularly plant growth-promoting bacteria (PGPB), have demonstrated their ability to enhance plant growth, protect against various stresses, and reduce the need for chemical inputs. Among the PGPB, Bacillus species have garnered attention due to their adaptability and commercial potential. Recent reports have highlighted Bacillus strains as biocontrol agents against phytopathogenic bacteria while concurrently promoting plant growth. We also examined Bacillus plant growth-promoting abilities in Arabidopsis thaliana seedlings. In this study, we assessed the potential of various Bacillus strains to control diverse phytopathogenic bacteria and inhibit quorum sensing using Chromobacterium violaceum as a model system. In conclusion, our results suggest that bacteria of the genus Bacillus hold significant potential for biotechnological applications. This includes developments aimed at reducing agrochemical use, promoting sustainable agriculture, and enhancing crop yield and protection.


Assuntos
Arabidopsis , Bacillus , Doenças das Plantas , Bacillus/fisiologia , Arabidopsis/microbiologia , Arabidopsis/crescimento & desenvolvimento , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , Percepção de Quorum , Chromobacterium/fisiologia , Chromobacterium/crescimento & desenvolvimento , Agentes de Controle Biológico/farmacologia , Desenvolvimento Vegetal , Plântula/microbiologia , Plântula/crescimento & desenvolvimento , Microbiologia do Solo
2.
Microb Ecol ; 87(1): 93, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39008123

RESUMO

Huanglongbing, also known as citrus greening, is currently the most devastating citrus disease with limited success in prevention and mitigation. A promising strategy for Huanglongbing control is the use of antimicrobials fused to a carrier protein (phloem protein of 16 kDa or PP16) that targets vascular tissues. This study investigated the effects of genetically modified citrus trees expressing Citrus sinensis PP16 (CsPP16) fused to human lysozyme and ß-defensin-2 on the soil microbiome diversity using 16S amplicon analysis. The results indicated that there were no significant alterations in alpha diversity, beta diversity, phylogenetic diversity, differential abundance, or functional prediction between the antimicrobial phloem-overexpressing plants and the control group, suggesting minimal impact on microbial community structure. However, microbiota diversity analysis revealed distinct bacterial assemblages between the rhizosphere soil and root environments. This study helps to understand the ecological implications of crops expressing phloem-targeted antimicrobials for vascular disease management, with minimal impact on soil microbiota.


Assuntos
Bactérias , Citrus , Microbiota , Floema , Doenças das Plantas , Rizosfera , Microbiologia do Solo , Floema/microbiologia , Floema/metabolismo , Bactérias/genética , Bactérias/classificação , Bactérias/metabolismo , Bactérias/isolamento & purificação , Doenças das Plantas/microbiologia , Citrus/microbiologia , Plantas Geneticamente Modificadas/microbiologia , Plantas Geneticamente Modificadas/genética , Filogenia , Metagenômica , Muramidase/metabolismo , Muramidase/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , beta-Defensinas/genética , RNA Ribossômico 16S/genética , Anti-Infecciosos/farmacologia , Anti-Infecciosos/metabolismo , Citrus sinensis/microbiologia , Raízes de Plantas/microbiologia
3.
Int J Mol Sci ; 25(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38474088

RESUMO

Members of the phloem protein 16 (PP16) gene family are induced by elicitors in rice and the corresponding proteins from cucurbits, which display RNA binding and intercellular transport activities, are accumulated in phloem sap. These proteins facilitate the movement of protein complexes through the phloem translocation flow and may be involved in the response to water deficit, among other functions. However, there is scant information regarding their function in other plants, including the identification of paralog genes in non-vascular plants and chlorophytes. In the present work, an evolutionary and structural analysis of the PP16 family in green plants (Viridiplantae) was carried out. Data mining in different databases indicated that PP16 likely originated from a larger gene present in an ancestral lineage that gave rise to chlorophytes and multicellular plants. This gene encodes a protein related to synaptotagmin, which is involved in vesicular transport in animal systems, although other members of this family play a role in lipid turnover in endomembranes and organelles. These proteins contain a membrane-binding C2 domain shared with PP16 proteins in vascular plants. In silico analysis of the predicted structure of the PP16 protein family identified several ß-sheets, one α-helix, and intrinsically disordered regions. PP16 may have been originally involved in vesicular trafficking and/or membrane maintenance but specialized in long-distance signaling during the emergence of the plant vascular system.


Assuntos
Proteínas de Plantas , Viridiplantae , Proteínas de Plantas/genética , Floema/metabolismo , Plantas/metabolismo , Transporte Biológico , Viridiplantae/metabolismo
4.
Curr Issues Mol Biol ; 45(9): 7538-7556, 2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37754259

RESUMO

Ouabain, an organic compound with the ability to strengthen the contraction of the heart muscle, was originally derived from plants. It has been observed that certain mammalian species, including humans, naturally produce ouabain, leading to its classification as a new type of hormone. When ouabain binds to Na+/K+-ATPase, it elicits various physiological effects, although these effects are not well characterized. Previous studies have demonstrated that ouabain, within the concentration range found naturally in the body (10 nmol/L), affects the polarity of epithelial cells and their intercellular contacts, such as tight junctions, adherens junctions, and gap junctional communication. This is achieved by activating signaling pathways involving cSrc and Erk1/2. To further investigate the effects of ouabain within the hormonally relevant concentration range (10 nmol/L), mRNA-seq, a high-throughput sequencing technique, was employed to identify differentially expressed transcripts. The discovery that the transcript encoding MYO9A was among the genes affected prompted an exploration of whether RhoA and its downstream effector ROCK were involved in the signaling pathways through which ouabain influences cell-to-cell contacts in epithelial cells. Supporting this hypothesis, this study reveals the following: (1) Ouabain increases the activation of RhoA. (2) Treatment with inhibitors of RhoA activation (Y27) and ROCK (C3) eliminates the enhancing effect of ouabain on the tight junction seal and intercellular communication via gap junctions. These findings further support the notion that ouabain acts as a hormone to emphasize the epithelial phenotype.

5.
Protein Expr Purif ; 200: 106167, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36057422

RESUMO

The ß1-subunit of the Na+/K+-ATPase is a cell membrane protein, beyond its classic functions, it is also a cell adhesion molecule. ß1-subunits on the lateral membrane of dog kidney epithelial cells trans-interact with ß1-subunits from another neighboring cells. The ß-ß interaction is essential for the formation and stabilization of intercellular junctions. Previous studies on site-directed mutagenesis and in silico revealed that the interaction interface involves residues 198-207 and 221-229. However, it is necessary to report the interaction interface at the structural level experimentally. Here, we describe the successful cloning, overexpression in E. coli, and purification of the extracellular domain of the ß1-subunit from inclusion bodies. Experimental characterization by size exclusion chromatography and DLS indicated similar hydrodynamic properties of the protein refolded. Structural analysis by circular dichroism and Raman spectroscopy revealed the secondary structures in the folded protein of type ß-sheet, α-helix, random coil, and turn. We also performed ß1-ß1 interaction assays with the recombinant protein, showing dimers' formation (6xHisß1-ß1). Given our results, the recombinant extracellular domain of the ß1-subunit is highly similar to the native protein, therefore the current work in our laboratory aims to characterize at the atomic level the interaction interface between EDß1.


Assuntos
Escherichia coli , ATPase Trocadora de Sódio-Potássio , Animais , Moléculas de Adesão Celular/metabolismo , Membrana Celular/metabolismo , Cães , Células Epiteliais , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , ATPase Trocadora de Sódio-Potássio/química , ATPase Trocadora de Sódio-Potássio/genética , ATPase Trocadora de Sódio-Potássio/metabolismo
6.
Int J Mol Sci ; 23(5)2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35269578

RESUMO

Citrus tristeza virus (CTV) is an important threat to the global citrus industry, causing severe economic losses worldwide. The disease management strategies are focused on vector control, tree culling, and the use of resistant varieties and rootstocks. Sweet orange (Citrus sinensis) trees showing either severe or mild CTV symptoms have been observed in orchards in Veracruz, Mexico, and were probably caused by different virus strains. To understand these symptomatic differences, transcriptomic analyses were conducted using asymptomatic trees. CTV was confirmed to be associated with infected plants, and mild and severe strains were successfully identified by a polymorphism in the coat protein (CP) encoding gene. RNA-Seq analysis revealed more than 900 significantly differentially expressed genes in response to mild and severe strains, with some overlapping genes. Importantly, multiple sequence reads corresponding to Citrus exocortis viroid and Hop stunt viroid were found in severe symptomatic and asymptomatic trees, but not in plants with mild symptoms. The differential gene expression profiling obtained in this work provides an overview of molecular behavior in naturally CTV-infected trees. This work may contribute to our understanding of citrus-virus interaction in more natural settings, which can help develop strategies for integrated crop management.


Assuntos
Citrus sinensis/virologia , Closterovirus/patogenicidade , Perfilação da Expressão Gênica/métodos , Proteínas de Plantas/genética , Vírus de Plantas/patogenicidade , Proteínas Virais/genética , Citrus sinensis/genética , Closterovirus/genética , Resistência à Doença , Regulação da Expressão Gênica de Plantas , Regulação Viral da Expressão Gênica , México , Doenças das Plantas/genética , Doenças das Plantas/virologia , Vírus de Plantas/genética , RNA-Seq , Virulência
7.
EMBO Rep ; 20(4)2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30833341

RESUMO

Post-translational modifications of histone H3 N-terminal tails are key epigenetic regulators of virulence gene expression and sexual commitment in the human malaria parasite Plasmodium falciparum Here, we identify proteolytic clipping of the N-terminal tail of nucleosome-associated histone H3 at amino acid position 21 as a new chromatin modification. A cathepsin C-like proteolytic clipping activity is observed in nuclear parasite extracts. Notably, an ectopically expressed version of clipped histone H3, PfH3p-HA, is targeted to the nucleus and integrates into mononucleosomes. Furthermore, chromatin immunoprecipitation and next-generation sequencing analysis identified PfH3p-HA as being highly enriched in the upstream region of six genes that play a key role in DNA replication and repair: In these genes, PfH3p-HA demarcates a specific 1.5 kb chromatin island adjacent to the open reading frame. Our results indicate that, in P. falciparum, the process of histone clipping may precede chromatin integration hinting at preferential targeting of pre-assembled PfH3p-containing nucleosomes to specific genomic regions. The discovery of a protease-directed mode of chromatin organization in P. falciparum opens up new avenues to develop new anti-malarials.


Assuntos
Replicação do DNA , Histonas/metabolismo , Malária Falciparum/parasitologia , Nucleossomos/metabolismo , Plasmodium falciparum/fisiologia , Regiões 5' não Traduzidas , Sequência de Aminoácidos , Imunoprecipitação da Cromatina , Expressão Ectópica do Gene , Eritrócitos/parasitologia , Regulação da Expressão Gênica , Histonas/química , Histonas/genética , Humanos , Inibidores de Proteases/farmacologia , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Proteólise/efeitos dos fármacos
8.
Plant Dis ; 105(5): 1490-1494, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33780269

RESUMO

Xylella fastidiosa is a xylem-inhabiting phytopathogenic bacterium that affects diverse agriculturally relevant crops. In Mexico, X. fastidiosa has been reported in the states of Baja California, Coahuila, and Querétaro. In order to determine the genetic diversity of this bacterium in Mexico, 408 grapevine samples were collected from the main producing states in México. For X. fastidiosa identification, real-time PCR and three-loci end-point PCR were employed. The genotyping of the subspecies was carried out using multilocus sequence typing and analysis, based on seven housekeeping genes: leuA, petC, malF, cysG, holC, nuoL, and gltT. The resulting sequences were compared with those present in extant databases. The presence of X. fastidiosa subsp. fastidiosa in the states of Baja California (sequence type 1), Coahuila (sequence type 1), and Querétaro was confirmed. The isolates from northern Mexico bear high similarity to grapevine isolates from the United States. However, the isolates from Querétaro showed significant differences with currently known sequences, showing that there is genetic variability among the X. fastidiosa subsp. fastidiosa populations from grapevines in northern and central Mexico.


Assuntos
Variação Genética , Doenças das Plantas , Fazendas , México , Estados Unidos , Xylella
9.
Int J Mol Sci ; 22(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34201937

RESUMO

The AVRPPHB SUSCEPTIBLE1 (PBS1) and RESISTANCE TO PSEUDOMONAS SYRINGAE 5 (RPS5) proteins are involved in signal transduction to evoke innate plant immune response. In Arabidopsis, PBS1 is cleaved by the AvrPphB (Pseudomonas phaseolicola Avirulence protein B) protease, activating RPS5 and turning in a hypersensitive response (HR). We searched for PBS1 orthologs to trace their origin and evolution. PBS1 orthologs were found in embryophytes and in other plant taxa but with lower similarity. PBS1 phylogenetic analysis indicates high divergence, suggesting that the decoy function described for Arabidopsis PBS1 might be associated with a small fraction of orthologs. Ancestral reconstruction analysis suggests an elevated diversity in the amino acid sequence within the described motifs. All the orthologs contain the conserved PBS1 kinase subdomains, whereas the cleavage motif is present in several embryophyte orthologs but absent in most other taxa. The putative resistance recognition motifs in PBS1 orthologs are highly diverse. PBS1 cleavage site motif is exposed in some 3D structure predictions, whereas it is not in others, suggesting different modes of regulation and functions in PBS1 orthologs. Our findings suggest that PBS1 originated in the lineage that gave rise to embryophytes, with the angiosperm sequences forming a separate clade from pteridophyte proteins.


Assuntos
Evolução Biológica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas/genética , Plantas/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Sequência de Aminoácidos , Sequência Conservada , Regulação da Expressão Gênica de Plantas , Modelos Moleculares , Filogenia , Fenômenos Fisiológicos Vegetais , Conformação Proteica , Proteínas Serina-Treonina Quinases/química , Transdução de Sinais , Relação Estrutura-Atividade
10.
Ann Hepatol ; 19(5): 507-515, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32592870

RESUMO

INTRODUCTION AND AIM: Occult hepatitis B virus infection (OBI) is characterized by the presence of replication-competent hepatitis B virus (HBV) DNA in the liver and/or serum of patients with undetectable levels of the HBV surface antigen (HBsAg). Due to the shared infection routes HIV positive patients are at higher risk of developing OBI, thus, the aim of this study was to determine the frequency of OBI in Mexican HIV-infected patients and to identify mutations in the HBV S gene that could be associated to the development of OBI. MATERIALS AND METHODS: Plasma samples from 50 HIV-infected patients with undetectable levels of the HBsAg were obtained and analyzed. The Core, PreS and S genes were amplified by nested PCR and sequenced by the Sanger method. To analyze HBV diversity in the OBI-positive patients, ten sequences of 762bp from the HBV S gene were selected, cloned, and subsequently sequenced for mutational analyses. RESULTS: OBI infection was found with a frequency of 36% (18/50). All the HBV sequences corresponded to the H genotype. The most common mutations were: C19Y, Q129H, E164D, and I195M, with a frequency of 44%, 36%, 39% and 48% respectively. CONCLUSIONS: In this study, we report the presence of OBI in a cohort of Mexican HIV-infected patients with an overall prevalence of 36%. Mutational analyses revealed that four non-silent mutations were frequent in different regions of the HBsAg gene, suggesting that they might be associated to the development of OBI in this population, nevertheless, further studies are required to determine their role in the pathogenesis of OBI.


Assuntos
Coinfecção , Infecções por HIV/virologia , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite B/virologia , Mutação , Adulto , Idoso , Análise Mutacional de DNA , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/etnologia , Hepatite B/sangue , Hepatite B/diagnóstico , Hepatite B/etnologia , Antígenos de Superfície da Hepatite B/sangue , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Epidemiologia Molecular , Taxa de Mutação , Fatores de Risco , Carga Viral
11.
Rev Argent Microbiol ; 49(1): 93-104, 2017.
Artigo em Espanhol | MEDLINE | ID: mdl-28298253

RESUMO

An ectomycorrhiza is a mutualistic symbiosis of paramount importance in forestry and tree production. One of the selection criteria of ectomycorrhizal fungi that has currently gained importance is their edibility due to the economic, ecological and cultural relevance of edible ectomycorrhizal mushrooms as a non-timber forest product. The effect of the inoculation with three edible ectomycorrhizal mushrooms: Laccaria laccata, Laccaria bicolor y Hebeloma leucosarx, which are widely sold in Mexico, on the growth and nutrient contents of Pinus greggii grown in an experimental substrate and a commercial substrate enriched with a slow-release fertilizer, was evaluated. Two years after sowing, differences in terms of shoot and root biomass and macro and micronutrient contents between inoculated and non-inoculated plants, were recorded independently of the fungal species and the substrate. Despite the fact that plants grown in the commercial substrate had higher growth and nutrient contents, their ectomycorrhizal colonization percentages were smaller than those of the plants grown in the experimental substrate. The differences in the nutrient transfer to the inoculated plant shoots among the evaluated fungal species were recorded. Ca mobilization by L. laccata, Na by L. bicolor and Mn by H. leucosarx were observed in the plants growing in the experimental substrate. It has been demonstrated that the selection of substrates constitutes an important factor in the production of ectomycorrhizal plants and that the three evaluated species of edible ectomycorrhizal mushrooms have an enormous potential in the controlled mycorrhization of P. greggii.


Assuntos
Micorrizas , Pinus , Agaricales , México , Nutrientes , Pinus/crescimento & desenvolvimento , Pinus/microbiologia , Raízes de Plantas , Plântula
12.
J Environ Sci Health B ; 50(2): 99-108, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25587779

RESUMO

The concentrations of hydrocarbons and organochlorine pesticides (OCPs), nutrients and tolerant microorganisms in an agricultural soil from a locality in Tepeaca, Puebla, Mexico, were determined to define its feasibility for bioremediation. The OCPs detected were heptachlor, aldrin, trans-chlordane, endosulfán I, endosulfán II, 1,1,1-bis-(4-chlorophenyl)-2,2-trichloroethane (4,4'-DDT), 1,1-bis-(4-chlorophenyl)-2,2-dichloroethene (4,4'-DDE) and endrin aldehyde, with values of 0.69-30.81 ng g(-1). The concentration of hydrocarbons in the soil of Middle Hydrocarbons Fraction (MHF), C10 to C28, was 4608-27,748 mg kg(-1) and 1117-19,610 mg kg(-1) for Heavy Hydrocarbons Fraction (HHF), C28 to C35, due to an oil spill from the rupture of a pipeline. The soil was deficient in nitrogen (0.03-0.07%) and phosphorus (0 ppm), and therefore it was advisable to fertilize to bio-stimulate the native microorganisms of soil. In the soil samples, hydrocarbonoclast fungi 3.72 × 10(2) to 44.6 × 10(2) CFU g(-1) d.s. and hydrocarbonoclast bacteria (0.17 × 10(5) to 8.60 × 10(5) CFU g(-1) d.s.) were detected, with a tolerance of 30,000 mg kg(-1) of diesel. Moreover, pesticideclast fungi (5.13 × 10(2) to 42.2 × 10(2) CFU g(-1) d.s.) and pesticideclast bacteria (0.15 × 10(5) to 9.68 × 10(5) CFU g(-1) d.s.) were determined with tolerance to 20 mg kg(-1) of OCPs. Fungi and bacteria tolerant to both pollutants were also quantified. Therefore, native microorganisms had potential to be stimulated to degrade hydrocarbons and pesticides or both pollutants. The concentration of pollutants and the microbial activity analyzed indicated that bioremediation of the soil contaminated with hydrocarbons and pesticides using bio-stimulation of native microorganisms was feasible.


Assuntos
Biodegradação Ambiental , Hidrocarbonetos Clorados/análise , Resíduos de Praguicidas/análise , Praguicidas/análise , Microbiologia do Solo , Poluentes do Solo/análise , Monitoramento Ambiental , Poluição Ambiental
13.
Theor Appl Genet ; 127(1): 231-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24121568

RESUMO

KEY MESSAGE: Identified SSR markers ( Xcfd49 and Xbarc183 ) linked with stem rust resistance for efficient use in marker-assisted selection and stacking of resistance genes in wheat breeding programs. More than 80 % of the worldwide wheat (Triticum aestivum L.) area is currently sown with varieties susceptible to the Ug99 race group of stem rust fungus. However, wheat lines Niini, Tinkio, Coni, Pfunye, Blouk, and Ripper have demonstrated Ug99 resistance at the seedling and adult plant stages. We mapped stem rust resistance in populations derived from crosses of a susceptible parent with each of the resistant lines. The segregation of resistance in each population indicated the presence of a single gene. The resistance gene in Niini mapped to short arm of chromosome 6D and was flanked by SSR markers Xcfd49 at distances of 3.9 cM proximal and Xbarc183 8.4 cM distal, respectively. The chromosome location of this resistance was validated in three other populations: PBW343/Coni, PBW343/Tinkio, and Cacuke/Pfunye. Resistance initially postulated to be conferred by the SrTmp gene in Blouk and Ripper was also linked to Xcfd49 and Xbarc183 on 6DS, but it was mapped proximal to Xbarc183 at a similar position to previously mapped genes Sr42 and SrCad. Based on the variation in diagnostic marker alleles, it is possible that Niini and Pfunye may carry different resistance genes/alleles. Further studies are needed to determine the allelic relationships between various genes located on chromosome arm 6DS. Our results provide valuable molecular marker and genetic information for developing Ug99 resistant wheat varieties in diverse germplasm and using these markers to tag the resistance genes in wheat breeding.


Assuntos
Basidiomycota , Cromossomos de Plantas , Resistência à Doença/genética , Doenças das Plantas/microbiologia , Triticum/genética , Mapeamento Cromossômico , Fenótipo , Triticum/microbiologia
14.
Plants (Basel) ; 12(15)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37570993

RESUMO

Long-distance signaling molecules in plants, including different RNA species, play a crucial role in the development and environmental responses. Among these mobile signals, the Translationally Controlled Tumor Protein (TCTP) mRNA is one of the most abundant. TCTP regulates cell-cycle progression and programmed cell death and is involved in responses to abiotic and biotic stress as well as plant regeneration, among other functions. Considering that the ability to induce plant regeneration is linked to a possible role of TCTP in vegetative propagation and asexual reproduction, we analyzed TCTP overexpression in a solanaceous plant model that can reproduce asexually by regeneration from stolons and tubers. Therefore, in this study, the effect of transient expression of Solanum tuberosum TCTP (StTCTP) on tuber development and vegetative propagation was described. StTCTP mRNA was shown to be transported long-distance. Additionally, transient overexpression of StTCTP resulted in sprouts with a greater diameter compared to control plants. Furthermore, the early stages of tuberization were induced compared to control plants, in which only mature tubers were observed. These results suggest a role of TCTP in vegetative propagation and asexual reproduction.

15.
Insects ; 14(10)2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37887819

RESUMO

Insects are under constant selective pressure, which has resulted in adaptations to novel niches such as crops. This is the case of the pest Melanaphis sacchari, the sugarcane aphid, native to Africa and currently spreading worldwide. The aphid undergoes successful parthenogenesis, causing important damage to a variety of crops and leading to important economic losses for farmers. A natural M. sacchari population grown in sorghum was studied to identify its microbiome through the sequencing of its 16S rDNA metagenome. A high proportion of Proteobacteria, followed by Firmicutes, Bacteroidetes, and Actinobacteria, was observed. We also detected Wolbachia, which correlates with the asexual reproduction of its host. M. sacchari was challenged in a bioassay with the antibiotics oxytetracycline and streptomycin, resulting in a dose-dependent decay of its survival rate. The possibility of controlling this pest by altering its microbiota is proposed.

16.
PLoS One ; 18(1): e0279681, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36701313

RESUMO

The pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has affected millions of people worldwide. Public health strategies to reduce viral transmission are based on widespread diagnostic testing to detect and isolate contagious patients. Several reverse transcription (RT)-PCR tests, along with other SARS-CoV-2 diagnostic assays, are available to attempt to cover the global demand. Loop-mediated isothermal amplification (LAMP) based methods have been established as rapid, accurate, point of care diagnostic tests for viral infections; hence, they represent an excellent alternative for SARS-CoV-2 detection. The aim of this study was to develop and describe molecular detection systems for SARS-CoV-2 based on RT-LAMP. Recombinant DNA polymerase from Bacillus stearothermophilus and thermostable engineered reverse transcriptase from Moloney Murine Leukemia Virus were expressed using a prokaryotic system and purified by fast protein liquid chromatography. These enzymes were used to set up fluorometric real time and colorimetric end-point RT-LAMP assays. Several reaction conditions were optimized such as reaction temperature, Tris-HCl concentration, and pH of the diagnostic tests. The key enzymes for RT-LAMP were purified and their enzymatic activity was determined. Standardized reaction conditions for both RT-LAMP assays were 65°C and a Tris-HCl-free buffer at pH 8.8. Colorimetric end-point RT-LAMP assay was successfully used for viral detection from clinical saliva samples with 100% sensitivity and 100% specificity compared to the results obtained by RT-qPCR based diagnostic protocols with Ct values until 30. The developed RT-LAMP diagnostic tests based on purified recombinant enzymes allowed a sensitive and specific detection of the nucleocapsid gene of SARS-CoV-2.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Camundongos , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Sensibilidade e Especificidade , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase em Tempo Real , Testes Diagnósticos de Rotina , RNA Viral/genética , Teste para COVID-19
17.
Life Sci Alliance ; 6(12)2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37813486

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) has the worst prognosis among all human cancers as it is highly resistant to chemotherapy. K-Ras mutations usually trigger the development and progression of PDAC. We hypothesized that compounds stabilizing the KRas4B/PDE6δ complex could serve as PDAC treatments. Using in silico approaches, we identified the small molecules C14 and P8 that reduced K-Ras activation in primary PDAC cells. Importantly, C14 and P8 significantly prevented tumor growth in patient-derived xenotransplants. Combined treatment with C14 and P8 strongly increased cytotoxicity in PDAC cell lines and primary cultures and showed strong synergistic antineoplastic effects in preclinical murine PDAC models that were superior to conventional therapeutics without causing side effects. Mechanistically, C14 and P8 reduced tumor growth by inhibiting AKT and ERK signaling downstream of K-RAS leading to apoptosis, specifically in PDAC cells. Thus, combined treatment with C14 and P8 may be a superior pharmaceutical strategy to improve the outcome of PDAC.


Assuntos
Antineoplásicos , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Camundongos , Animais , Linhagem Celular Tumoral , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Antineoplásicos/farmacologia , Neoplasias Pancreáticas
18.
Plant J ; 67(1): 130-44, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21435051

RESUMO

Phloem-transported signals play an important role in regulating plant development and in orchestrating responses to environmental stimuli. Among such signals, phloem-mobile RNAs have been shown to play an important role as long-distance signaling agents. At maturity, angiosperm sieve elements are enucleate, and thus transcripts in the phloem translocation stream probably originate from the nucleate companion cells. In the present study, a pumpkin (Cucurbita maxima) phloem transcriptome was used to test for the presence of common motifs within the promoters of this unique set of genes, which may function to coordinate expression in cells of the vascular system. A bioinformatics analysis of the upstream sequences from 150 Arabidopsis genes homologous to members of the pumpkin phloem transcriptome identified degenerate sequences containing CT/GA- and GT/CA-rich motifs that were common to many of these promoters. Parallel studies performed on genes shown previously to be expressed in phloem tissues identified similar motifs. An expanded analysis, based on homologs of the pumpkin phloem transcriptome from cucumber (Cucumis sativus), identified similar sets of common motifs within the promoters of these genes. Promoter analysis offered support for the hypothesis that these motifs regulate expression within the vascular system. Our findings are discussed in terms of a role for these motifs in coordinating gene expression within the companion cell/sieve element system. These motifs could provide a useful bioinformatics tool for genome-wide screens on plants for which phloem tissues cannot readily be obtained.


Assuntos
Arabidopsis/genética , Cucurbita/genética , Floema/genética , Regiões Promotoras Genéticas/genética , Região 5'-Flanqueadora/genética , Biologia Computacional , Cucumis sativus/genética , DNA de Plantas/genética , Bases de Dados de Ácidos Nucleicos , Genes de Plantas/genética , Oryza/genética , Folhas de Planta/genética , Plantas Geneticamente Modificadas/genética , Populus/genética , RNA Mensageiro/genética , RNA de Plantas/genética , Sequências Repetitivas de Ácido Nucleico , Homologia de Sequência do Ácido Nucleico , Transcriptoma
19.
Front Plant Sci ; 13: 818107, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35283930

RESUMO

CmNACP1 mRNA has been shown to move long distance through the phloem in Cucurbita maxima (pumpkin) and through a graft junction. Whereas the phloem transport of several different mRNAs has been documented in other systems as well, its function remains, for most of these RNAs, largely unknown. To gain insight into the possible role of these RNAs, we searched for the closest homologs of CmNACP1 in Arabidopsis, a model plant much more amenable for analysis. A phylogenetic approach using the predicted NAC domain indicated that ANAC059, ANAC092, ANAC079, ANAC100, ANAC046, and ANAC087 form a single clade with CmNACP1. In the present work, we analyzed the possible function of the ANAC087 gene in more detail. The promoter region of this gene directed expression in the vasculature, and also in trichomes, stem, apexes, and developing flowers which supports the notion that ANAC087 and CmNACP1 are orthologs. Overexpression of the ANAC087 gene induced increased branching in inflorescence stem, and also development of ectopic or aerial rosettes in T1 and T2 plants. Furthermore, overexpression of ANAC087 leads to accelerated leaf senescence in 44 days post-germination (dpg). Interestingly, a similar phenotype was observed in plants expressing the ANAC087 gene upstream region, also showing an increase in ANAC087 transcript levels. Finally, the results shown in this work indicate a role for ANAC087 in leaf senescence and also in rosette development.

20.
J Virol Methods ; 302: 114466, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35065084

RESUMO

In the present study, a droplet digital PCR assay was developed for detection of Tomato brown rugose fruit virus, a new Tobamovirus of tomato and other solanaceous plants, which expands the diagnostic strategies for this pathogen. Candidate reference DNA material was also obtained to be employed as positive control in tomato and pepper samples. Recombinant plasmids encode for ToBRFV coat protein (CP-ToBRFV) gene and Solanum lycopersicum GAPDH fragments, and CP-ToBRFV and Capsicum annuum GAPDH. To our knowledge, this is the first report of ToBRFV detection in tomato and pepper seeds using ddPCR.


Assuntos
Solanum lycopersicum , Tobamovirus , Frutas , Doenças das Plantas , Reação em Cadeia da Polimerase , Sementes , Tobamovirus/genética
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