Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Insect Physiol ; 133: 104284, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34256034

RESUMO

In the circadian system, the clock gene vrille (vri) is an essential component of the second feedback loop, being responsible in Drosophila for the rhythmicity of the Clock (Clk) gene transcription by its repression. Here we studied vri in a fruit fly pest, the Tephritidae Anastrepha fraterculus, aimingtoinvestigate its molecular evolution and expression patterns from whole-head extracts. We used a combination of transcriptomic, genomic and gene walking strategies to sequence and characterize Afravri in male and female head transcriptomes of A. fraterculus and detected two putative isoforms that may correspond to A and D vri isoforms of Drosophila. Both isoforms produced a full-length sequence that translates to 842 amino acids. While the protein sequence showed significant divergence to orthologous sequences from other organisms, the bZIP domain was highly conserved. Molecular evolutionary analyses showed that vri in higher Diptera flies has been evolving under positive selection. A more detailed analysis showed positive selection also in Tephritidae with 29 sites evolving under positive selection in comparison with Drosophilidae. Real time expression analysis in LD and DD conditions showed cyclic expression of Afravri mRNA with oscillation opposite to AfraClk, suggesting that VRI may also behave in Anastrepha as a transcriptional repressor of Clk, providing another indication that higher Diptera might share common interlocked transcript-translation feedback loops (TTFLs) mechanisms that differ from other insects in target genes.


Assuntos
Proteínas CLOCK/metabolismo , Evolução Molecular , Proteínas de Insetos/genética , Tephritidae/genética , Fatores de Transcrição/genética , Animais , Feminino , Proteínas de Insetos/metabolismo , Masculino , Tephritidae/metabolismo , Fatores de Transcrição/metabolismo
2.
Front Endocrinol (Lausanne) ; 11: 561256, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33329381

RESUMO

The nuclear receptor PPARγ is essential to maintain whole-body glucose homeostasis and insulin sensitivity, acting as a master regulator of adipogenesis, lipid, and glucose metabolism. Its activation through natural or synthetic ligands induces the recruitment of coactivators, leading to transcription of target genes such as cytokines and hormones. More recently, post translational modifications, such as PPARγ phosphorylation at Ser273 by CDK5 in adipose tissue, have been linked to insulin resistance trough the dysregulation of expression of a specific subset of genes. Here, we investigate how this phosphorylation may disturb the interaction between PPARγ and some coregulator proteins as a new mechanism that may leads to insulin resistance. Through cellular and in vitro assays, we show that PPARγ phosphorylation inhibition increased the activation of the receptor, therefore the increased recruitment of PGC1-α and TIF2 coactivators, whilst decreases the interaction with SMRT and NCoR corepressors. Moreover, our results show a shift in the coregulators interaction domains preferences, suggesting additional interaction interfaces formed between the phosphorylated PPARγ and some coregulator proteins. Also, we observed that the CDK5 presence disturb the PPARγ-coregulator's synergy, decreasing interaction with PGC1-α, TIF2, and NCoR, but increasing coupling of SMRT. Finally, we conclude that the insulin resistance provoked by PPARγ phosphorylation is linked to a differential coregulators recruitment, which may promote dysregulation in gene expression.


Assuntos
Resistência à Insulina/fisiologia , PPAR gama/metabolismo , Serina/metabolismo , Células 3T3 , Adipócitos/metabolismo , Animais , Células COS , Chlorocebus aethiops , Quinase 5 Dependente de Ciclina/genética , Quinase 5 Dependente de Ciclina/metabolismo , Células HEK293 , Humanos , Camundongos , PPAR gama/genética , Fosforilação/fisiologia , Serina/genética
3.
Sci Rep ; 7(1): 2194, 2017 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-28526847

RESUMO

We studied two species of closely related South American fruit flies, Anastrepha fraterculus and Anastrepha obliqua which, despite being able to interbreed, still show some ecological and reproductive differences. Because part of these differences, such as host and mate preferences, may be related to olfactory perception, we focused our investigation on the differential expression of Odorant-binding protein (OBP) gene family, which participate in initial steps of the olfactory signal transduction cascade. We investigated patterns of expression of eight OBP genes by qPCR in male and female head tissues of both species. The expression patterns of these OBPs suggest that some OBP genes are more likely involved with the location of food resources, while others seem to be associated with mate and pheromone perception. Furthermore, the expression patterns obtained at different reproductive stages indicate that OBP expression levels changed significantly after mating in males and females of both species. All eight OBP genes analyzed here showed significant levels of differential expression between A. fraterculus and A. obliqua, suggesting that they may hold important roles in their olfactory perception differences, and consequently, may potentially be involved in their differentiation.


Assuntos
Expressão Gênica , Receptores Odorantes/genética , Tephritidae/genética , Animais , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Masculino , Receptores Odorantes/metabolismo , Especificidade da Espécie , Tephritidae/metabolismo , Transcriptoma
4.
Sci Rep ; 6: 17480, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26818909

RESUMO

The West Indian fruit fly, Anastrepha obliqua, is an important agricultural pest in the New World. The use of pesticide-free methods to control invasive species such as this reinforces the search for genes potentially useful in their genetic control. Therefore, the study of chemosensory proteins involved with a range of responses to the chemical environment will help not only on the understanding of the species biology but may also help the development of environmentally friendly pest control strategies. Here we analyzed the expression patterns of three OBP genes, Obp19d_2, Obp56a and Obp99c, across different phases of A. obliqua development by qPCR. In order to do so, we tested eight and identified three reference genes for data normalization, rpl17, rpl18 and ef1a, which displayed stability for the conditions here tested. All OBPs showed differential expression on adults and some differential expression among adult stages. Obp99c had an almost exclusive expression in males and Obp56a showed high expression in virgin females. Thereby, our results provide relevant data not only for other gene expression studies in this species, as well as for the search of candidate genes that may help in the development of new pest control strategies.


Assuntos
Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Genes de Insetos , Proteínas de Insetos/genética , Receptores Odorantes/genética , Tephritidae/crescimento & desenvolvimento , Tephritidae/genética , Algoritmos , Animais , Feminino , Estudos de Associação Genética , Proteínas de Insetos/metabolismo , Estágios do Ciclo de Vida/genética , Masculino , Receptores Odorantes/metabolismo , Padrões de Referência , Reprodução/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...