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1.
Braz. j. biol ; 84: e248656, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345542

RESUMO

Abstract Several species of Cichla successfully colonized lakes and reservoirs of Brazil, since the 1960's, causing serious damage to local wildlife. In this study, 135 peacock bass were collected in a reservoir complex in order to identify if they represented a single dominant species or multiple ones, as several Cichla species have been reported in the basin. Specimens were identified by color pattern, morphometric and meristic data, and using mitochondrial markers COI, 16S rDNA and Control Region (CR). Overlapping morphological data and similar coloration patterns prevented their identification using the taxonomic keys to species identification available in the literature. However, Bayesian and maximum likelihood from sequencing data demonstrated the occurrence of a single species, Cichla kelberi. A single haplotype was observed for the 16S and CR, while three were detected for COI, with a dominant haplotype present in 98.5% of the samples. The extreme low diversity of the transplanted C. kelberi evidenced a limited number of founding maternal lineages. The success of this colonization seems to rely mainly on abiotic factors, such as increased water transparency of lentic environments that favor visual predators that along with the absence of predators, have made C. kelberi a successful invader of these reservoirs.


Resumo Muitas espécies de Cichla colonizaram com sucesso lagos e reservatórios do Brasil desde os anos 1960, causando graves prejuízos à vida selvagem nesses locais. Neste estudo, 135 tucunarés foram coletados em um complexo de reservatórios a fim de identificar se representavam uma espécie dominante ou múltiplas espécies, uma vez que diversas espécies de Cichla foram registradas na bacia. Os espécimes foram identificados com base na coloração, dados morfométricos e merísticos, e por marcadores mitocondriais COI, 16S rDNA e Região Controle (RC). A sobreposição dos dados morfométricos e o padrão similar de coloração impediram a identificação utilizando as chaves de identificação disponíveis na literatura. Entretanto, as análises bayesiana e de máxima verossimilhança de dados moleculares demonstraram a ocorrência de uma única espécie, Cichla kelberi. Um único haplótipo foi observado para o 16S e RC, enquanto três foram detectados para o COI, com um haplótipo dominante presente em 98,5% das amostras. A baixa diversidade nos exemplares introduzidos de C. kelberi evidenciou um número limitado de linhagens maternas fundadoras. O sucesso da invasão parece depender de fatores abióticos, como a maior transparência da água de ambientes lênticos que favorece predadores visuais que, atrelado à ausência de predadores, fez do C. kelberi um invasor bem-sucedido nesses reservatórios.


Assuntos
Animais , Ciclídeos/genética , Filogenia , Variação Genética/genética , Haplótipos/genética , Lagos , Teorema de Bayes
2.
Braz. j. biol ; 84: e248359, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345547

RESUMO

Abstract Bacterial leaf blight (BLB) is one of the major rice diseases in Malaysia. This disease causes substantial yield loss as high as 70%. Development of rice varieties which inherited BLB resistant traits is a crucial approach to promote and sustain rice industry in Malaysia. Hence, this study aims were to enhance BLB disease resistant characters of high yielding commercial variety MR219 through backcross breeding approach with supporting tool of marker-assisted selection (MAS). Broad spectrum BLB resistance gene, Xa7 from donor parent IRBB7 were introgressed into the susceptible MR219 (recurrent parent) using two flanking markers ID7 and ID15. At BC3F4, we managed to generate 19 introgressed lines with homozygous Xa7 gene and showed resistant characteristics as donor parent when it was challenged with Xanthomonas oryzae pv. oryzae through artificial inoculation. Recurrent parent MR219 and control variety, MR263 were found to be severely infected by the disease. The improved lines exhibited similar morphological and yield performance characters as to the elite variety, MR219. Two lines, PB-2-107 and PB-2-34 were chosen to be potential lines because of their outstanding performances compared to parent, MR219. This study demonstrates a success story of MAS application in development of improved disease resistance lines of rice against BLB disease.


Resumo A mancha bacteriana das folhas (BLB) é uma das principais doenças do arroz na Malásia. Essa doença causa perdas substanciais de rendimento de até 70%. O desenvolvimento de variedades de arroz que herdaram características de resistência ao BLB é uma abordagem crucial para promover e sustentar a indústria do arroz na Malásia. Portanto, o objetivo deste estudo foi aumentar os caracteres BLB resistentes a doenças da variedade comercial MR219 de alto rendimento por meio de uma abordagem de cruzamento retrocruzamento com ferramenta de apoio de seleção assistida por marcador (MAS). O gene de resistência a BLB de amplo espectro, Xa7 do pai doador IRBB7, foi introgressado no MR219 suscetível (pai recorrente) usando dois marcadores flanqueadores ID7 e ID15. No BC3F4, conseguimos gerar 19 linhagens introgressadas com o gene Xa7 homozigoto e apresentamos características de resistência como genitor doador quando desafiado com Xanthomonas oryzae pv. oryzae por inoculação artificial. O pai recorrente MR219 e a variedade controle, MR263, estavam gravemente infectados pela doença. As linhas melhoradas exibiram características morfológicas e de desempenho de rendimento semelhantes às da variedade elite, MR219. Duas linhas, PB-2-107 e PB-2-34, foram escolhidas como linhas potenciais por causa de seus desempenhos excelentes em comparação com a mãe, MR219. Este estudo demonstra uma história de sucesso de aplicação de MAS no desenvolvimento de linhas de arroz melhoradas com resistência a doenças contra a doença BLB.


Assuntos
Oryza , Xanthomonas , Doenças das Plantas/genética , Resistência à Doença/genética , Melhoramento Vegetal
3.
Braz. j. biol ; 84: e249664, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345558

RESUMO

Abstract The impact of antibiotics on growth, cocoon production was assessed in addition to isolation and characterization of bacteria associated with silkworm gut of infected larvae. Larval rearing was maintained at recommended conditions of temperature and humidity. Silkworm larvae showing abnormal symptoms were collected from the control group and dissected for gut collection. Bacteria were isolated from the gut content by spreading on agar plates and incubated at 37 °C for 48 hrs. Bacterial identification and phylogenetic analysis were carried out by 16S rRNA gene sequencing. The isolated bacteria were subjected to antimicrobial susceptibility test (disc diffusion methods) by using Penicillin (10 µg/mL), Tetracycline (30 µg/mL), Amoxicillin (25 µg/mL), Ampicillin (10 µg/mL), and Erythromycin (15 µg/mL). All isolated strains showed positive results for the catalase test. We isolated and identified bacterial strains (n = 06) from the gut of healthy and diseased silkworm larvae. Based on the 16S rRNA gene sequence, isolated bacteria showed close relation with Serratia, Bacillus, and Pseudomonas spp. Notably, 83.3% of strains were resistant to Penicillin, Tetracycline, Amoxicillin, Ampicillin, and Erythromycin but 16.6% showed antibiotic susceptibility to the above-mentioned commonly used antibiotics. Silkworm larvae fed on penicillin-treated leaves showed significant improvement in larval weight, larval length, and cocoon production. Significantly higher larval weight (6.88g), larval length (5.84cm), and cocoon weight (1.33g) were recorded for larvae fed on leaves treated with penicillin as compared to other antibiotics. Isolated bacterial strains showed close relation with Serratia spp., Bacillus spp. and Pseudomonas spp.


Resumo O impacto dos antibióticos no crescimento e na produção do casulo foi avaliado, além do isolamento e caracterização das bactérias associadas ao intestino de larvas infectadas do bicho-da-seda. A criação das larvas foi mantida nas condições recomendadas de temperatura e umidade. As larvas do bicho-da-seda com sintomas anormais foram coletadas do grupo controle e dissecadas para coleta do intestino. As bactérias foram isoladas do conteúdo intestinal por espalhamento em placas de ágar e incubadas a 37° C durante 48 horas. A identificação bacteriana e a análise filogenética foram realizadas pelo sequenciamento do gene 16S rRNA. As bactérias isoladas foram submetidas a teste de sensibilidade antimicrobiana (métodos de difusão em disco) com penicilina (10 µg / mL), tetraciclina (30 µg / mL), amoxicilina (25 µg / mL), ampicilina (10 µg / mL) e eritromicina (15 µg / mL). Todas as cepas isoladas apresentaram resultados positivos para o teste da catalase. Isolamos e identificamos cepas bacterianas (n = 06) do intestino de larvas de bicho-da-seda saudáveis e doentes. Com base na sequência do gene 16S rRNA, as bactérias isoladas mostraram estreita relação com Serratia, Bacillus e Pseudomonas spp. Notavelmente, 83,3% das cepas eram resistentes a penicilina, tetraciclina, amoxicilina, ampicilina e eritromicina, mas 16,6% mostraram suscetibilidade aos antibióticos comumente usados mencionados acima. As larvas do bicho-da-seda alimentadas com folhas tratadas com penicilina apresentaram melhora significativa no peso larval, comprimento larval e produção de casulo. Peso larval significativamente maior (6,88g), comprimento larval (5,84cm) e peso do casulo (1,33g) foram registrados para larvas alimentadas com folhas tratadas com penicilina, em comparação com outros antibióticos. Cepas bacterianas isoladas mostraram estreita relação com Serratia spp., Bacillus spp. e Pseudomonas spp.


Assuntos
Animais , Bombyx , Antibacterianos/farmacologia , Filogenia , Bactérias/genética , RNA Ribossômico 16S/genética , Testes de Sensibilidade Microbiana , Larva
4.
Braz. j. biol ; 84: e254253, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1350308

RESUMO

Abstract During the present study, specimens were collected from selected sites of Cholistan desert and Kalabagh Game Reserve, Punjab province, Pakistan. Each captured specimen was tagged with voucher number and morphometric measurements were taken. The average snout to vent length was 172.559±1.40 mm and average weight was 92.1±1.30 g. The DNA of Uromastyx hardwickii was amplified and sequenced using 16S rRNA primer set. The obtained DNA sequence has shown reliable and clear species identification. After trimming ambiguous bases, the obtained 16S rRNA fragment was 520 bp while 16S rRNA fragments aligned with closely matched sequence from NCBI comprised of 510 bp. Closely matched sequences of genus Uromastyx were retrieved from NCBI in blast searches. Neighbour-joining tree of genus Uromastyx was constructed based on p-distance using MEGA X. The mean intraspecific variation was 0.095±0.01 while intraspecific variation was ranging from 0-1%. Similarly, interspecific variation of Uromastyx hardwikii with Saara asmussi, Uromastyx alfredschmidti, Uromastyx geyri, Uromastyx thomasi, Uromastyx alfredschmidti was 0-12%, 0-19%, 0-19%, 0-20%, 12-19% respectively. The newly produced DNA was submitted to NCBI and accession number was obtained (MW052563.1). Results of current study provided information about the molecular and morphological identification of Genus Uromastyx. In our recommendation, comprehensive molecular based identification of Pakistan's reptiles is required to report any new or subspecies from country.


Resumo Durante o presente estudo, os espécimes foram coletados em locais selecionados do deserto do Cholistan e da Reserva de Caça de Kalabagh, província de Punjab, Paquistão. Cada espécime capturado foi etiquetado com o número do comprovante e medidas morfométricas foram realizadas. O comprimento médio do focinho à cloaca foi de 172,559 ± 1,40 mm, e o peso médio foi de 92,1 ± 1,30 g. O DNA de Uromastyx hardwickii foi amplificado e sequenciado usando o conjunto de primer 16S rRNA. A sequência de DNA obtida mostrou identificação de espécies confiável e clara. Após o corte de bases ambíguas, o fragmento de rRNA 16S obtido tinha 520 pb, enquanto os fragmentos de rRNA 16S alinhados com a sequência próxima do NCBI composta por 510 pb. Sequências semelhantes do gênero Uromastyx foram recuperadas do NCBI em pesquisas de explosão. A árvore de união de vizinhos do gênero Uromastyx foi construída com base na distância-p usando MEGA X. A variação intraespecífica média foi de 0,095 ± 0,01, enquanto a variação intraespecífica foi de 0-1%. Da mesma forma, a variação interespecífica de Uromastyx hardwikii com Saara asmussi, Uromastyx alfredschmidti, Uromastyx geyri, Uromastyx thomasi, Uromastyx alfredschmidti foi de 0-12%, 0-19%, 0-19%, 0-20%, 12-19%, respectivamente. O DNA recém-produzido foi submetido ao NCBI e o número de acesso foi obtido (MW052563.1). Os resultados do estudo atual forneceram informações sobre a identificação molecular e morfológica do Gênero Uromastyx. Em nossa recomendação, a identificação de base molecular abrangente de répteis do Paquistão é necessária para relatar qualquer nova ou subespécie do país.


Assuntos
Animais , Lagartos , Paquistão , Filogenia , Variação Genética/genética , RNA Ribossômico 16S
5.
Braz. j. biol ; 84: e250575, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1350309

RESUMO

Abstract Cancer is a fatal malignancy and its increasing worldwide prevalence demands the discovery of more sensitive and reliable molecular biomarkers. To investigate the GINS1 expression level and its prognostic value in distinct human cancers using a series of multi-layered in silico approach may help to establish it as a potential shared diagnostic and prognostic biomarker of different cancer subtypes. The GINS1 mRNA, protein expression, and promoter methylation were analyzed using UALCAN and Human Protein Atlas (HPA), while mRNA expression was further validated via GENT2. The potential prognostic values of GINS1 were evaluated through KM plotter. Then, cBioPortal was utilized to examine the GINS1-related genetic mutations and copy number variations (CNVs), while pathway enrichment analysis was performed using DAVID. Moreover, a correlational analysis between GINS1 expression and CD8+ T immune cells and a the construction of gene-drug interaction network was performed using TIMER, CDT, and Cytoscape. The GINS1 was found down-regulated in a single subtypes of human cancer while commonly up-regulated in 23 different other subtypes. The up-regulation of GINS1 was significantly correlated with the poor overall survival (OS) of Liver Hepatocellular Carcinoma (LIHC), Lung Adenocarcinoma (LUAD), and Kidney renal clear cell carcinoma (KIRC). The GINS1 was also found up-regulated in LIHC, LUAD, and KIRC patients of different clinicopathological features. Pathways enrichment analysis revealed the involvement of GINS1 in two diverse pathways, while few interesting correlations were also documented between GINS1 expression and its promoter methylation level, CD8+ T immune cells level, and CNVs. Moreover, we also predicted few drugs that could be used in the treatment of LIHC, LUAD, and KIRC by regulating the GINS1 expression. The expression profiling of GINS1 in the current study has suggested it a novel shared diagnostic and prognostic biomarker of LIHC, LUAD, and KIRC.


Resumo O câncer é uma doença maligna fatal e sua crescente prevalência mundial exige a descoberta de biomarcadores moleculares mais sensíveis e confiáveis. Investigar o nível de expressão de GINS1 e seu valor prognóstico em cânceres humanos distintos, usando uma série de abordagens in silico em várias camadas, pode ajudar a estabelecê-lo como um potencial biomarcador de diagnóstico e prognóstico compartilhado de diferentes subtipos de câncer. O mRNA de GINS1, a expressão da proteína e a metilação do promotor foram analisados ​​usando UALCAN e Human Protein Atlas (HPA), enquanto a expressão de mRNA foi posteriormente validada via GENT2. Os valores prognósticos potenciais de GINS1 foram avaliados por meio do plotter KM. Em seguida, o cBioPortal foi utilizado para examinar as mutações genéticas relacionadas ao GINS1 e as variações do número de cópias (CNVs), enquanto a análise de enriquecimento da via foi realizada usando DAVID. Além disso, uma análise correlacional entre a expressão de GINS1 e células imunes T CD8 + e a construção de uma rede de interação gene-droga foi realizada usando TIMER, CDT e Cytoscape. O GINS1 foi encontrado regulado negativamente em um único subtipo de câncer humano, enquanto comumente regulado positivamente em 23 outros subtipos diferentes. A regulação positiva de GINS1 foi significativamente correlacionada com a sobrevida global pobre (OS) de Carcinoma Hepatocelular de Fígado (LIHC), Adenocarcinoma de Pulmão (LUAD) e Carcinoma de Células Claras Renais de Rim (KIRC). O GINS1 também foi encontrado regulado positivamente em pacientes LIHC, LUAD e KIRC de diferentes características clínico-patológicas. A análise de enriquecimento de vias revelou o envolvimento de GINS1 em duas vias diversas, enquanto poucas correlações interessantes também foram documentadas entre a expressão de GINS1 e seu nível de metilação do promotor, nível de células imunes T CD8 + e CNVs. Além disso, também previmos poucos medicamentos que poderiam ser usados ​​no tratamento de LIHC, LUAD e KIRC, regulando a expressão de GINS1. O perfil de expressão de GINS1 no estudo atual sugeriu que é um novo biomarcador de diagnóstico e prognóstico compartilhado de LIHC, LUAD e KIRC.


Assuntos
Humanos , Carcinoma de Células Renais/genética , Neoplasias Renais/genética , Neoplasias Hepáticas , Prognóstico , Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica , Regulação para Cima , Proteínas de Ligação a DNA , Variações do Número de Cópias de DNA
6.
Braz. j. biol ; 84: e255605, 2024. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355882

RESUMO

Abstract Combining ability analysis provides useful information for the selection of parents, also information regarding the nature and magnitude of involved gene actions. Crops improvement involves strategies for enhancing yield potentiality and quality components. Targeting the improvement of respective characters in bitter gourd, combining ability and genetic parameters for 19 characters were estimated from a 6×6 full diallel analysis technique. The results revealed that the variances due to general combining ability (GCA) and specific combining ability (SCA) were highly significant for most of the important characters. It indicated the importance of both additive and non-additive gene actions. GCA variances were higher in magnitude than SCA variances for all the characters studied indicating the predominance of the additive gene effects in their inheritance. The parent P2 (BG 009) appeared as the best general combiner for earliness; P1 (BG 006) for number of fruits, average single fruit weight and fruit yield; P4 (BG 027) for node number of first female flower and days to seed fruit maturity; P3 (BG 011) for fruit length and thickness of the fruit flesh; P5 (BG 033) for 100-seed weight; and P6 for number of nodes per main vine. The SCA effect as well as reciprocal effect was also significant for most of the important characters in different crosses.


Resumo A análise da capacidade de combinação fornece informações úteis para a seleção dos pais, também informações sobre a natureza e a magnitude das ações dos genes envolvidos. A melhoria das safras envolve estratégias para aumentar a potencialidade da produção e os componentes de qualidade. Visando ao aprimoramento dos respectivos caracteres em cabaça-amarga, capacidade de combinação e parâmetros genéticos para 19 caracteres, foram estimados a partir de uma técnica de análise dialélica completa 6 × 6. Os resultados revelaram que as variâncias, devido à capacidade geral de combinação (GCA) e capacidade específica de combinação (SCA), foram altamente significativas para a maioria dos caracteres importantes. Indicou a importância das ações gênicas aditivas e não aditivas. As variâncias GCA foram maiores em magnitude do que as variâncias SCA para todos os caracteres estudados, indicando a predominância dos efeitos do gene aditivo em sua herança. O pai P2 (BG 009) apareceu como o melhor combinador geral para o início; P1 (BG 006) para número de frutos, peso médio de um único fruto e produção de frutos; P4 (BG 027) para número de nó da primeira flor fêmea e dias para a maturidade do fruto da semente; P3 (BG 011) para comprimento do fruto e espessura da polpa do fruto; P5 (BG 033) para peso de 100 sementes; e P6 para o número de nós por videira principal. O efeito SCA, bem como o efeito recíproco, também foi significativo para a maioria dos personagens importantes em cruzamentos diferentes.


Assuntos
Momordica charantia , Produtos Agrícolas , Flores , Melhoria de Qualidade , Frutas/genética
7.
Braz. j. biol ; 84: e254816, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355894

RESUMO

Abstract Pakistan is an agricultural country and fisheries play a very important role in the economic development of the country. Different diseases are prevalent in Pakistani fish but information related to the causative agents is not well-known. Keeping in view the significance of bacterial pathogens as the causative agents of multiple fish diseases, the present study was conducted for identification, characterization and analysis of virulence genes of Aeromonas spp. isolated from diseased fishes. A total of fifty fish samples having multiple clinical indications were collected from different fish farms of district Kasur, Punjab Pakistan. For isolation of Aeromonas spp. samples were enriched and inoculated on Aeromonas isolation medium. Isolates were identified and characterized by different biochemical tests, Analytical Profile Index (API) 20E kit and Polymerase Chain Reaction (PCR) assays. All isolates were screened for three putative virulence genes including aerolysin (aer), haemolysin (hyl) and heat labile cytotonic enterotoxin (alt). Seven isolates of Aeromonas (A.) hydrophila were retrieved and identified based on API 20E. These isolates were further confirmed as A. hydrophila on the basis of PCR assays. Three isolates were detected positive for the presence of virulence genes (alt and hyl). Whereas aerolysin (aer) gene was not present in any of A. hydrophila isolates. The present study confirmed A. hydrophila as the causative agent of epizootic ulcerative syndrome and motile Aeromonas septicemia in fish farms of district Kasur, Punjab Pakistan. Moreover, detection of two virulence genes (alt and hyl) in A. hydrophila isolates is a threat for fish consumers of study area.


Resumo O Paquistão é um país agrícola, onde a pesca desempenha um papel muito importante para o desenvolvimento econômico. Diferentes doenças são prevalentes em peixes do Paquistão, mas as informações relacionadas aos agentes causadores não são bem conhecidas. Tendo em vista a importância dos patógenos bacterianos como agentes causadores de múltiplas doenças em peixes, o presente estudo foi conduzido para identificação, caracterização e análise de genes de virulência de isolados de Aeromonas spp. de peixes doentes. Foram coletadas 50 amostras de peixes com múltiplas indicações clínicas em diferentes fazendas do distrito de Kasur, Punjab, Paquistão. Para isolar Aeromonas spp., as amostras foram enriquecidas e inoculadas em meio de isolamento. Os isolados foram identificados e caracterizados por diferentes testes bioquímicos, kit Analytical Profile Index (API) 20E, e ensaios de reação em cadeia da polimerase (PCR). Todos os isolados foram selecionados para três genes de virulência putativos, incluindo aerolisina (aer), hemolisina (hyl) e enterotoxina citotônica termolábil (alt). Sete isolados de Aeromonas hydrophila foram recuperados e identificados com base no API 20E. Esses isolados foram posteriormente confirmados como A. hydrophila de acordo com ensaios de PCR. Três isolados indicaram a presença de genes de virulência (alt e hyl), enquanto o gene aerolisina (aer) não esteve presente em nenhum dos isolados de A. hydrophila. O presente estudo confirmou A. hydrophila como o agente causador da síndrome ulcerativa epizoótica e septicemia móvel por Aeromonas em fazendas de peixes, no distrito de Kasur, Punjab, Paquistão. Além disso, a detecção de dois genes de virulência (alt e hyl) em isolados de A. hydrophila é uma ameaça para os consumidores de peixes da área de estudo.


Assuntos
Animais , Infecções por Bactérias Gram-Negativas/veterinária , Infecções por Bactérias Gram-Negativas/epidemiologia , Aeromonas/genética , Paquistão , Aeromonas hydrophila/genética , Enterotoxinas/genética , Peixes
8.
Methods Mol Biol ; 2564: 75-97, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36107338

RESUMO

Directed evolution has revolutionized the way scientists create new biomolecules not found in nature. Error-prone polymerase chain reaction (PCR) introduces random mutations and was used to evolve jellyfish and coral fluorescent proteins in bacteria. We describe a novel method for the directed evolution of a far-red fluorescent protein in E. coli. The new method used genes to produce fluorophores inside E. coli and allowed changing the native fluorophore, phycocyanobilin, for a second small-molecule fluorophore, biliverdin. The directed evolution blueshifted the fluorescence, which enhanced the quantum yield to produce a brighter fluorescent protein. Finally, the evolution selected fluorescent proteins that expressed in large quantities in E. coli. The evolved fluorescent protein was named the small ultra-red fluorescent protein (smURFP) and was biophysically as bright as the enhanced green fluorescent protein (EGFP). This chapter describes the materials and methods used to evolve a far-red fluorescent protein in bacteria. While the focus is a fluorescent protein, the protocol is adaptable for the evolution of other biomolecules in bacteria when using a proper selection strategy.


Assuntos
Antozoários , Escherichia coli , Animais , Antozoários/genética , Antozoários/metabolismo , Biliverdina/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Fluorescência , Mutação
9.
Methods Mol Biol ; 2564: 99-119, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36107339

RESUMO

Fluorescent proteins have revolutionized cell biology and cell imaging through their use as genetically encoded tags. Structural biology has been pivotal in understanding how their unique fluorescent properties manifest through the formation of the chromophore and how the spectral properties are tuned through interaction networks. This knowledge has in turn led to the construction of novel variants with new and improved properties. Here we describe the process by which fluorescent protein structures are determined, starting from recombinant protein production to structure determination by molecular replacement. We also describe how to incorporate and determine the structures of proteins containing non-natural amino acids. Recent advances in protein engineering have led to reprogramming of the genetic code to allow incorporation of new chemistry at designed residue positions, with fluorescent proteins being at the forefront of structural studies in this area. The impact of such new chemistry on protein structure is still limited; the accumulation of more protein structures will undoubtedly improve our understanding and ability to engineer proteins with new chemical functionality.


Assuntos
Aminoácidos , Código Genético , Aminoácidos/química , Corantes , Cristalização , Engenharia de Proteínas/métodos , Proteínas Recombinantes/genética
10.
Methods Mol Biol ; 2564: 185-201, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36107342

RESUMO

The protocol in this chapter describes a method to label endogenous proteins using a self-complementing split green fluorescent protein (split GFP1-10/11) in a human cell line. By directly delivering Cas9/sgRNA ribonucleoprotein (RNP) complexes through nucleofection, this protocol allows for the efficient integration of GFP11 into a specific genomic locus via CRISPR-Cas9-mediated homology-directed repair (HDR). We use the GFP11 sequence in the form of a single-stranded DNA (ssDNA) as an HDR template. Because the ssDNA with less than 200 nucleotides used here is commercially synthesized, this approach remains cloning-free. The integration of GFP11 is performed in cells stably expressing GFP1-10, thereby inducing fluorescence reconstitution. Subsequently, such a reconstituted signal is analyzed using fluorescence flow cytometry for estimating knock-in efficiencies and enriching the GFP-positive cell population. Finally, the enriched cells can be visualized using fluorescence microscopy.


Assuntos
Sistemas CRISPR-Cas , DNA de Cadeia Simples , Linhagem Celular , Proteínas de Fluorescência Verde/genética , Humanos , Nucleotídeos , Ribonucleoproteínas/genética
11.
Methods Mol Biol ; 2564: 203-211, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36107343

RESUMO

Fluorescent proteins (FPs) remarkably advanced the study of cellular biology of plants. The most common application is their use as reporter proteins to determine the subcellular localization of a protein of interest (POI) by endogenous expression of a suitable FP-POI fusion construct in plant cells. In this chapter we describe three approaches, namely, particle bombardment, protoplast transformation, and Agrobacterium infiltration, to transiently express such fusion constructs in plant cells of different species. These approaches are versatile and can be utilized for diverse fluorescent protein-based applications.


Assuntos
Agrobacterium , Plantas , Agrobacterium/genética , Agrobacterium/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células Vegetais/metabolismo , Plantas/genética , Plantas/metabolismo , Transporte Proteico
12.
Methods Mol Biol ; 2564: 213-222, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36107344

RESUMO

Fluorescent proteins within fluorescent fusions have been reported to affect cellular growth fitness via altering native protein function and intracellular localization. Here we report in detail a procedure to analyze the growth characteristics of yeast cells expressing such fusions in comparison to unmodified parental strain. This approach can serve as an initial step in fluorescent protein characterization in vivo.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomycetales , Corantes/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomycetales/metabolismo
13.
Methods Mol Biol ; 2564: 269-286, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36107348

RESUMO

The expression of plant cysteine oxidase (PCO) enzyme in Saccharomyces cerevisiae enables the Arg/Cys N-degron pathway (Cys-NDP) for selective protein degradation that, in plants, functions as direct oxygen perception mechanism. A synthetic construct based on the plant Cys-NDP substrate related to apetala 2.12 (RAP2.12), the dual luciferase oxygen reporter (DLOR), exploits the N-terminal Cys of RAP2.12, and its oxygen-dependent degradation through the Cys-NDP. The luminescent output of DLOR can be used as a proxy for intracellular oxygen dynamics in budding yeast. Replacement of the luciferase reporter of the DLOR with fluorescent proteins would furthermore facilitate the imaging of reporter dynamics in living cells. In this chapter, we describe the methods for delivering the DLOR synthetic construct to yeast and calibrating its output by means of oxygen quantification in the culture with a physical oxygen sensor. We explain the setup needed to carry out hypoxic treatments with several colonies as replicates. We also describe the method to measure oxygen concentration in the culture, the closest indication of intracellular oxygen levels, as a way that would serve to calibrate the DLOR output. Finally, we propose a strategy to replace the luminescent reporters in the DLOR with fluorescent proteins to visualize oxygen dynamics in vivo.


Assuntos
Cisteína Dioxigenase , Saccharomyces cerevisiae , Cisteína/metabolismo , Cisteína Dioxigenase/metabolismo , Luciferases/metabolismo , Oxigênio/metabolismo , Proteólise , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
14.
Methods Mol Biol ; 2564: 317-323, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36107351

RESUMO

Protein-protein interactions play a vital role in the cellular physiology of living organisms. Among several available approaches, co-immunoprecipitation (co-IP) has emerged as a reliable method to investigate such interactions. The underlying principle is to retrieve a bait protein from a protein extract using bait-specific antibodies and thereby indirectly capture the interacting partner proteins. However, bait-specific antibodies are not always available, and the genetic fusion of a peptide tag offers an alternative. An extensive range of peptide tags and the tag-specific antibodies are available nowadays. Fluorescent proteins are widely used protein tags for co-IP experiments. In this chapter, we describe a method to co-immunoprecipitate the fluorescently tagged candidate protein with its interacting partners from the crude plant cell extracts using green fluorescent protein (GFP)-trap magnetic beads.


Assuntos
Ligante de CD40 , Células Vegetais , Anticorpos , Extratos Celulares , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Imunoprecipitação , Peptídeos , Células Vegetais/metabolismo
15.
Zool Res ; 44(1): 3-19, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36171715

RESUMO

Confused geographical structure of a population and mitonuclear discordance are shaped by a combination of rapid changes in population demographics and shifts in ecology. In this study, we generated a time-calibrated phylogeny of Scutiger boulengeri, an endemic Xizang alpine toad occurring in mountain streams on the Qinghai-Xizang (Tibet) Plateau (QTP). Based on three mitochondrial DNA (mtDNA) genes, eight clades were assigned to three deeply divergent lineages. Analysis of nuclear DNA (nuDNA) genes revealed three distinct clusters without geographic structure, indicating significantly high rates of gene flow. Coalescent theory framework analysis (approximate Bayesian computation model DIYABC and Migrate-N) suggested that divergence of the main intraspecific clusters was the result of hybridization after secondary contact in the Holocene around 0.59 million years ago (Ma). The ratio of mtDNA F ST (fixation index) to nuDNA F ST was 2.3, thus failing to show male-biased dispersal. Geographic cline analysis showed that a wide hybrid zone was initially established in southwestern China, without significant reproductive isolation but with strong introgression in S. boulengeri, suggesting high hybrid fitness. Furthermore, mtDNA genes exhibited isolation by distance (IBD) while nuDNA genes exhibited significant isolation by environment (IBE). Results suggested that mitonuclear discordance may have initially been caused by geographic isolation, followed by precipitation-mediated hybridization, producing a wide hybrid zone and geographic structure confusion of nuDNA genes in S. boulengeri. This study indicated that complicated historical processes may have led to specific genetic patterns, with a specific climate factor facilitating gene flow in the system.


Assuntos
DNA Mitocondrial , Fluxo Gênico , Animais , Teorema de Bayes , DNA Mitocondrial/genética , Hibridização Genética , Masculino , Filogenia
16.
Methods Mol Biol ; 2570: 85-102, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36156776

RESUMO

Although SELEX can identify high-affinity aptamers, Doped-SELEX is often performed post-selection for the identification of better variants. Starting from a partially randomized (doped) library derived from an already identified aptamer, this method can screen rapidly several thousand substitutions in order to identify those that can improve the binding of the aptamers. It can also highlight the positions that do not tolerate substitutions, which suggest they are crucial for the interaction of the aptamer with its target. High-throughput sequencing (HTS), also named next-generation sequencing (NGS), can dramatically improve this method by studying millions of sequences. This high number of sequences ensures a statistically robust analysis of variants even for those with a low frequency in the library. It can reduce the number of selection rounds and provide a more in-depth analysis of the positions that are crucial for the aptamer affinity. In this chapter, we provide a protocol to simultaneously study and improve an aptamer using Doped-SELEX and HTS analysis, including the design of the doped library, the selection, HTS, and analysis. This protocol could be useful to improve the affinity of an aptamer and to reduce its size as well as to improve ribozyme.


Assuntos
Aptâmeros de Nucleotídeos , RNA Catalítico , Aptâmeros de Nucleotídeos/genética , Aptâmeros de Nucleotídeos/metabolismo , Biblioteca Gênica , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Técnica de Seleção de Aptâmeros/métodos
17.
Methods Mol Biol ; 2570: 155-173, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36156781

RESUMO

Fluorogenic RNA aptamers are synthetic RNAs that have been evolved by in vitro selection methods to bind and light up conditionally fluorescent organic ligands. Compared with other probes for RNA detection, they are less invasive than hybridization-based methods (FISH, molecular beacons) and are considerably smaller than fluorescent protein-recruiting systems (MS2, Pumilio variants). Fluorogenic aptamers have therefore found widespread use as genetically encodable tags for RNA detection in live cells and have also been used in combination with riboswitches to construct versatile metabolite sensors for in vitro use. Their success builds on a fundamental understanding of their three-dimensional structure to explain the mechanisms of ligand interaction and to rationally design functional aptamer devices. In this protocol, we describe a supramolecular FRET-based structure probing method for fluorogenic aptamers that exploits distance- and orientation-dependent energy transfer efficiencies between site-specifically incorporated fluorescent nucleoside analogs and non-covalently bound ligands, exemplified by 4-cyanoindol riboside (4CI) and the DMHBI+-binding RNA aptamer Chili. This method yields structural restraints that bridge the gap between traditional low-resolution secondary structure probing methods and more elaborate high-resolution methods such as X-ray crystallography and NMR spectroscopy.


Assuntos
Aptâmeros de Nucleotídeos , Riboswitch , Aptâmeros de Nucleotídeos/química , Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/química , Ligantes , Nucleosídeos , RNA/genética
18.
Methods Mol Biol ; 2570: 223-234, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36156786

RESUMO

RNA aptamers can be genetically encoded in cells to probe and manipulate cellular function. The usefulness of aptamers in mammalian cells is limited by low accumulation and degradation by ribonucleases. Expression of circular RNA aptamers using the Tornado expression system achieves high stability and an abundance of intracellular RNA aptamers. With this method, RNA aptamers with otherwise minimal activity become potent inhibitors. Here, we describe protocols to characterize circular RNA aptamers expressed using Tornado. Included are methods to assess stability, abundance, subcellular localization, and target binding by circular RNA aptamers.


Assuntos
Aptâmeros de Nucleotídeos , Animais , Aptâmeros de Nucleotídeos/química , Mamíferos/genética , RNA/química , RNA Circular , Ribonucleases/metabolismo
19.
Methods Mol Biol ; 2570: 243-269, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36156788

RESUMO

Small-molecule sensing is a major issue as they can serve both in fundamental science and as makers of various diseases, contaminations, or even environment pollution. RNA aptamers are single-stranded nucleic acids that can adopt different conformations and specifically recognize a wide range of ligands, making them good candidates to develop biosensors of small molecules. Recently, light-up RNA aptamers have been introduced and used as starting building blocks of RNA-based fluorogenic biosensors. They are typically made of three domains: a reporter domain (a light-up aptamer), connected to a sensor domain (another aptamer) via a communication module. The latter is instrumental as being in charge of information transmission between the sensor and the reporting domains. Here we present an ultrahigh-throughput screening procedure to develop RNA-based fluorogenic biosensors by selecting optimized communication modules through an exhaustive functional exploration of every possible sequence permutation using droplet-based microfluidics and next-generation sequencing.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Aptâmeros de Nucleotídeos/genética , Técnicas Biossensoriais/métodos , Ligantes , Microfluídica/métodos , RNA/genética
20.
Methods Mol Biol ; 2578: 121-141, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36152284

RESUMO

This chapter describes an epitope-directed approach to generate antipeptide monoclonal antibodies to multiple nonoverlapping protein sites using a cocktail of fusion peptides as immunogen. It provides a step-by-step protocol on how antigenic peptides on a target protein can be identified by in silico prediction and discusses considerations for final peptide selection. Each antigenic peptide (10-20 amino acids long) is displayed as three-copy inserts on the surface exposed loop of a thioredoxin scaffold protein. The corresponding DNA coding sequence specifying the tripeptide insert flanked by Gly-Ser-Gly-Ser-Gly linkers is cloned in-frame into the Rsr II site of the thioredoxin gene in the pET-32a vector. The presence of a C-terminal polyhistidine tag (His6-tag) allows the soluble fusion proteins to be purified by one-step native immobilized metal affinity chromatography (IMAC) to greater than 95% purity. Multiple thioredoxin fusion proteins are mixed in equimolar concentrations and used as an immunogen cocktail for animal immunization. The use of short antigenic peptides of known sequence facilitates direct epitope mapping requiring only small mutagenesis scan peptide libraries in the multipin peptide format.


Assuntos
Anticorpos Monoclonais , Biblioteca de Peptídeos , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/genética , Antígenos , Mapeamento de Epitopos/métodos , Epitopos , Peptídeos/genética , Tiorredoxinas/genética
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