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1.
BMC Biol ; 18(1): 84, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32620168

RESUMO

BACKGROUND: Heliconius butterflies are widely distributed across the Neotropics and have evolved a stunning array of wing color patterns that mediate Müllerian mimicry and mating behavior. Their rapid radiation has been strongly influenced by hybridization, which has created new species and allowed sharing of color patterning alleles between mimetic species pairs. While these processes have frequently been observed in widespread species with contiguous distributions, many Heliconius species inhabit patchy or rare habitats that may strongly influence the origin and spread of species and color patterns. Here, we assess the effects of historical population fragmentation and unique biology on the origins, genetic health, and color pattern evolution of two rare and sparsely distributed Brazilian butterflies, Heliconius hermathena and Heliconius nattereri. RESULTS: We assembled genomes and re-sequenced whole genomes of eight H. nattereri and 71 H. hermathena individuals. These species harbor little genetic diversity, skewed site frequency spectra, and high deleterious mutation loads consistent with recent population bottlenecks. Heliconius hermathena consists of discrete, strongly isolated populations that likely arose from a single population that dispersed after the last glacial maximum. Despite having a unique color pattern combination that suggested a hybrid origin, we found no genome-wide evidence that H. hermathena is a hybrid species. However, H. hermathena mimicry evolved via introgression, from co-mimetic Heliconius erato, of a small genomic region upstream of the color patterning gene cortex. CONCLUSIONS: Heliconius hermathena and H. nattereri population fragmentation, potentially driven by historical climate change and recent deforestation, has significantly reduced the genetic health of these rare species. Our results contribute to a growing body of evidence that introgression of color patterning alleles between co-mimetic species appears to be a general feature of Heliconius evolution.


Assuntos
Evolução Biológica , Borboletas/genética , Ecossistema , Genoma , Hibridização Genética , Animais , Brasil , Feminino , Masculino , Sequenciamento Completo do Genoma
2.
Front Plant Sci ; 9: 1376, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30283484

RESUMO

The goal of this research was to generate networks of co-expressed genes to explore the genomic responses of Rhizophora mangle L. populations to contrasting environments and to use gene network analysis to investigate their capacity for adaptation in the face of historical and future perturbations and climatic changes. RNA sequencing data were generated for R. mangle samples collected under field conditions from contrasting climate zones in the equatorial and subtropical regions of Brazil. A gene co-expression network was constructed using Pearson's correlation coefficient, showing correlations among 78,364 transcriptionally coordinated genes. Each region exhibited two distinct network profiles; genes correlated with the oxidative stress response showed higher relative expression levels in subtropical samples than in equatorial samples, whereas genes correlated with the hyperosmotic salinity response, heat response and UV response had higher expression levels in the equatorial samples than in the subtropical samples. In total, 992 clusters had enriched ontology terms, which suggests that R. mangle is under higher stress in the equatorial region than in the subtropical region. Increased heat may thus pose a substantial risk to species diversity at the center of its distribution range in the Americas. This study, which was performed using trees in natural field conditions, allowed us to associate the specific responses of genes previously described in controlled environments with their responses to the local habitat where the species occurs. The study reveals the effects of contrasting environments on gene expression in R. mangle, shedding light on the different abiotic variables that may contribute to the genetic divergence previously described for the species through the use of simple sequence repeats (SSRs). These effects may result from two fundamental processes in evolution, namely, phenotypic plasticity and natural selection.

3.
Artigo em Inglês | MEDLINE | ID: mdl-26944308

RESUMO

Peptidase inhibitors (PIs) are essential proteins involved in plant resistance to herbivorous insects, yet many insect species are able to escape the negative effects of these molecules. We compared the effects of acute and chronic ingestion of soybean peptidase inhibitors (SPIs) on Spodoptera frugiperda and Diatraea saccharalis, two Lepidoptera species with different sensitivities to SPI ingestion. We analyzed the trypsin and chymotrypsin gene expression profiles in both species. Acute exposure of S. frugiperda to the inhibitors activated seven genes (SfChy5, SfChy9, SfChy19, SfChy22, SfTry6, SfTry8, and SfTry10), whereas chronic exposure activated 16 genes (SfChy2, SfChy4, SfChy5, SfChy8, SfChy9, SfChy11, SfChy12, SfChy15, SfChy17, SfChy21, SfChy22, SfTry6, SfTry8, SfTry9, SfTry10, and SfTry12). By contrast, the challenge of D. saccharalis with SPIs did not differentially induce the expression of trypsin- or chymotrypsin-encoding genes, with the exception of DsChy7. Bayesian phylogenetic analysis of S. frugiperda trypsin protein sequences revealed two gene clades: one composed of genes responsive to the SPIs and a second composed of the unresponsive genes. D. saccharalis trypsin proteins were clustered nearest to the S. frugiperda unresponsive genes. Overall, our findings support a hypothesized mechanism of resistance of Noctuidae moths to SPIs, involving gene number expansion of trypsin and chymotrypsin families and regulation of gene expression, which could also explain the variable susceptibility between S. frugiperda and D. saccharalis to these plant inhibitors.


Assuntos
Quimotripsina/genética , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glycine max/química , Inibidores de Proteases/farmacologia , Spodoptera/efeitos dos fármacos , Spodoptera/genética , Tripsina/genética , Animais , Modelos Moleculares , Conformação Proteica , Especificidade da Espécie , Spodoptera/enzimologia , Tripsina/química
4.
Sci Rep ; 5: 12051, 2015 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-26159228

RESUMO

A previously described DNA sequence generator algorithm (DNA-SGA) using error-correcting codes has been employed as a computational tool to address the evolutionary pathway of the genetic code. The code-generated sequence alignment demonstrated that a residue mutation revealed by the code can be found in the same position in sequences of distantly related taxa. Furthermore, the code-generated sequences do not promote amino acid changes in the deviant genomes through codon reassignment. A Bayesian evolutionary analysis of both code-generated and homologous sequences of the Arabidopsis thaliana malate dehydrogenase gene indicates an approximately 1 MYA divergence time from the MDH code-generated sequence node to its paralogous sequences. The DNA-SGA helps to determine the plesiomorphic state of DNA sequences because a single nucleotide alteration often occurs in distantly related taxa and can be found in the alternative codon patterns of noncanonical genetic codes. As a consequence, the algorithm may reveal an earlier stage of the evolution of the standard code.


Assuntos
DNA/análise , Modelos Genéticos , Algoritmos , Arabidopsis/enzimologia , Arabidopsis/genética , Teorema de Bayes , Códon , DNA/química , Evolução Molecular , Malato Desidrogenase/classificação , Malato Desidrogenase/genética , Filogenia , Polimorfismo de Nucleotídeo Único
5.
Insect Biochem Mol Biol ; 58: 1-11, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25600115

RESUMO

Trypsins and chymotrypsins are well-studied serine peptidases that cleave peptide bonds at the carboxyl side of basic and hydrophobic L-amino acids, respectively. These enzymes are largely responsible for the digestion of proteins. Three primary processes regulate the activity of these peptidases: secretion, precursor (zymogen) activation and substrate-binding site recognition. Here, we present a detailed phylogenetic analysis of trypsins and chymotrypsins in three orders of holometabolous insects and reveal divergent characteristics of Lepidoptera enzymes in comparison with those of Coleoptera and Diptera. In particular, trypsin subsite S1 was more hydrophilic in Lepidoptera than in Coleoptera and Diptera, whereas subsites S2-S4 were more hydrophobic, suggesting different substrate preferences. Furthermore, Lepidoptera displayed a lineage-specific trypsin group belonging only to the Noctuidae family. Evidence for facilitated trypsin auto-activation events were also observed in all the insect orders studied, with the characteristic zymogen activation motif complementary to the trypsin active site. In contrast, insect chymotrypsins did not seem to have a peculiar evolutionary history with respect to their mammal counterparts. Overall, our findings suggest that the need for fast digestion allowed holometabolous insects to evolve divergent groups of peptidases with high auto-activation rates, and highlight that the evolution of trypsins led to a most diverse group of enzymes in Lepidoptera.


Assuntos
Evolução Biológica , Quimotripsina/metabolismo , Insetos/enzimologia , Tripsina/metabolismo , Animais , Sítios de Ligação , Quimotripsina/química , Besouros/enzimologia , Dípteros/enzimologia , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Lepidópteros/enzimologia , Peptídeo Hidrolases/química , Filogenia , Estrutura Terciária de Proteína , Tripsina/química
6.
Biochim Biophys Acta ; 1832(2): 365-74, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23200924

RESUMO

BACKGROUND: Several Rho GTPase-activating proteins (RhoGAPs) are implicated in tumor progression through their effects on Rho GTPase activity. ARHGAP21 is a RhoGAP with increased expression in head and neck squamous cell carcinoma and with a possible role in glioblastoma tumor progression, yet little is known about the function of ARHGAP21 in cancer cells. Here we studied the role of ARHGAP21 in two prostate adenocarcinoma cell lines, LNCaP and PC3, which respectively represent initial and advanced stages of prostate carcinogenesis. RESULTS: ARHGAP21 is located in the nucleus and cytoplasm of both cell lines and its depletion resulted in decreased proliferation and increased migration of PC3 cells but not LNCaP cells. In PC3 cells, ARHGAP21 presented GAP activity for RhoA and RhoC and induced changes in cell morphology. Moreover, its silencing altered the expression of genes involved in cell proliferation and cytoskeleton organization, as well as the endothelin-1 canonical pathway. CONCLUSIONS: Our results reveal new functions and signaling pathways regulated by ARHGAP21, and indicate that it could contribute to prostate cancer progression.


Assuntos
Adenocarcinoma/patologia , Movimento Celular , Proliferação de Células , Proteínas Ativadoras de GTPase/fisiologia , Neoplasias da Próstata/patologia , Adenocarcinoma/metabolismo , Sequência de Bases , Linhagem Celular Tumoral , Primers do DNA , Proteínas Ativadoras de GTPase/genética , Inativação Gênica , Humanos , Marcação In Situ das Extremidades Cortadas , Masculino , Neoplasias da Próstata/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
7.
Mol Biol Evol ; 28(1): 79-85, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20624849

RESUMO

Aminoacyl-transfer RNA (tRNA) synthetases (aaRS) are key players in translation and act early in protein synthesis by mediating the attachment of amino acids to their cognate tRNA molecules. In plants, protein synthesis may occur in three subcellular compartments (cytosol, mitochondria, and chloroplasts), which requires multiple versions of the protein to be correctly delivered to its proper destination. The organellar aaRS are nuclear encoded and equipped with targeting information at the N-terminal sequence, which enables them to be specifically translocated to their final location. Most of the aaRS families present organellar proteins that are dual targeted to mitochondria and chloroplasts. Here, we examine the dual targeting behavior of aaRS from an evolutionary perspective. Our results show that Arabidopsis thaliana aaRS sequences are a result of a horizontal gene transfer event from bacteria. However, there is no evident bias indicating one single ancestor (Cyanobacteria or Proteobacteria). The dual-targeted aaRS phylogenetic relationship was characterized into two different categories (paralogs and homologs) depending on the state recovered for both dual-targeted and cytosolic proteins. Taken together, our results suggest that the dual-targeted condition is a gain-of-function derived from gene duplication. Selection may have maintained the original function in at least one of the copies as the additional copies diverged.


Assuntos
Aminoacil-tRNA Sintetases/genética , Proteínas de Arabidopsis/genética , Arabidopsis/enzimologia , Arabidopsis/genética , Evolução Biológica , Proteínas de Arabidopsis/classificação , Proteínas de Bactérias/classificação , Proteínas de Bactérias/genética , Bases de Dados de Proteínas , Expressão Gênica , Transferência Genética Horizontal , Análise em Microsséries , Dados de Sequência Molecular , Filogenia , Mapeamento de Interação de Proteínas
8.
J Biol Chem ; 285(40): 30654-65, 2010 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-20682788

RESUMO

Proteins found in the root exudates are thought to play a role in the interactions between plants and soil organisms. To gain a better understanding of protein secretion by roots, we conducted a systematic proteomic analysis of the root exudates of Arabidopsis thaliana at different plant developmental stages. In total, we identified 111 proteins secreted by roots, the majority of which were exuded constitutively during all stages of development. However, defense-related proteins such as chitinases, glucanases, myrosinases, and others showed enhanced secretion during flowering. Defense-impaired mutants npr1-1 and NahG showed lower levels of secretion of defense proteins at flowering compared with the wild type. The flowering-defective mutants fca-1, stm-4, and co-1 showed almost undetectable levels of defense proteins in their root exudates at similar time points. In contrast, root secretions of defense-enhanced cpr5-2 mutants showed higher levels of defense proteins. The proteomics data were positively correlated with enzymatic activity assays for defense proteins and with in silico gene expression analysis of genes specifically expressed in roots of Arabidopsis. In conclusion, our results show a clear correlation between defense-related proteins secreted by roots and flowering time.


Assuntos
Arabidopsis/metabolismo , Flores/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Arabidopsis/genética , Flores/genética , Perfilação da Expressão Gênica , Proteínas de Plantas/genética , Raízes de Plantas/genética , Proteômica
9.
Clin Hemorheol Microcirc ; 43(3): 217-21, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19847056

RESUMO

Iron deficiency is a systemic disorder, which affects a variety of different cell types and is one of the most frequent diseases throughout the world. The influence of iron deficiency upon erythrocyte deformability is controversial and could be a consequence of membrane peroxidation damage or cross linking of membrane proteins. The aim of this study was to determine the overall elasticity (the deformability of the entire cell is evaluated) of iron deficient red blood cells (RBC) using laser optical tweezers. In this study, the laser trapped the cell and the elasticity was then analyzed measuring cell deformation at six different drag velocities. Twenty-five RBCs from 11 healthy blood donors (controls) and 7 patients with iron deficiency anemia were analyzed. Iron deficiency subjects were classified into 3 groups based on Hb concentration for statistical analysis (group I: Hb = 7.0-7.9; group II: 8.0-10.2 and group III: 7.0-10.2 g/dl). The results showed an increased rigidity in the iron deficiency of deficient red blood cells when compared to normal control blood cells, and, this impaired deformability seems to be correlated to the hemoglobin concentration. In conclusion, the results obtained by optical tweezers showed that iron deficiency affects the elasticity of whole RBC.


Assuntos
Anemia Ferropriva/sangue , Deformação Eritrocítica , Eritrócitos/metabolismo , Adulto , Viscosidade Sanguínea , Estudos de Casos e Controles , Elasticidade , Membrana Eritrocítica/efeitos da radiação , Humanos , Pinças Ópticas
10.
BMC Bioinformatics ; 10: 454, 2009 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-20043823

RESUMO

BACKGROUND: Protein-protein interactions (PPIs) constitute one of the most crucial conditions to sustain life in living organisms. To study PPI in Arabidopsis thaliana we have developed AtPIN, a database and web interface for searching and building interaction networks based on publicly available protein-protein interaction datasets. DESCRIPTION: All interactions were divided into experimentally demonstrated or predicted. The PPIs in the AtPIN database present a cellular compartment classification (C3) which divides the PPI into 4 classes according to its interaction evidence and subcellular localization. It has been shown in the literature that a pair of genuine interacting proteins are generally expected to have a common cellular role and proteins that have common interaction partners have a high chance of sharing a common function. In AtPIN, due to its integrative profile, the reliability index for a reported PPI can be postulated in terms of the proportion of interaction partners that two proteins have in common. For this, we implement the Functional Similarity Weight (FSW) calculation for all first level interactions present in AtPIN database. In order to identify target proteins of cytosolic glutamyl-tRNA synthetase (Cyt-gluRS) (AT5G26710) we combined two approaches, AtPIN search and yeast two-hybrid screening. Interestingly, the proteins glutamine synthetase (AT5G35630), a disease resistance protein (AT3G50950) and a zinc finger protein (AT5G24930), which has been predicted as target proteins for Cyt-gluRS by AtPIN, were also detected in the experimental screening. CONCLUSIONS: AtPIN is a friendly and easy-to-use tool that aggregates information on Arabidopsis thaliana PPIs, ontology, and sub-cellular localization, and might be a useful and reliable strategy to map protein-protein interactions in Arabidopsis. AtPIN can be accessed at http://bioinfo.esalq.usp.br/atpin.


Assuntos
Proteínas de Arabidopsis/química , Arabidopsis/metabolismo , Mapeamento de Interação de Proteínas/métodos , Software , Proteínas de Arabidopsis/metabolismo , Sítios de Ligação , Bases de Dados de Proteínas
11.
Genomics Proteomics Bioinformatics ; 4(3): 182-8, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17127216

RESUMO

Proteins containing an Rho GTPase-activating protein (RhoGAP) domain work as molecular switches involved in the regulation of diverse cellular functions. The ability of these GTPases to regulate a wide number of cellular processes conies from their interactions with multiple effectors and inhibitors, including the RhoGAP family, which stimulates their intrinsic GTPase activity. Here, a phylogenetic approach was applied to study the evolutionary relationship among 59 RhoGAP domain-containing proteins. The sequences were aligned by their RhoGAP domains and the phylogenetic hypotheses were generated using Maximum Parsimony and Bayesian analyses. The character tracing of two traits, GTPase activity and presence of other domains, indicated a significant phylogenetic signal for both of them.


Assuntos
Proteínas Ativadoras de GTPase/química , Filogenia , Algoritmos , Animais , Teorema de Bayes , Biologia Computacional , Bases de Dados de Proteínas , Evolução Molecular , GTP Fosfo-Hidrolases/química , Técnicas Genéticas , Humanos , Internet , Estrutura Terciária de Proteína , Proteômica , Software
12.
Rev. saúde pública ; 31(5): 502-7, 1997.
Artigo em Português | LILACS | ID: lil-234442

RESUMO

A campanha anti-rábica no Brasil é realizada anualmente utilizando a vacina de cérebro de camundongos lactentes Fuenzalida-Palacios. A resposta imune humoral de cäes vacinados durante as campanhas foi analisada objetivando avaliar se os cäes apresentavam título protetor (0,5 UI/ml), 12 meses após a vacinaçäo, e quantos deles alcançam esse título 30 dias após o reforço vacinal. Foram analisadas 341 amostras de soro de cäes domiciliados (259 do município de Säo Paulo e 82 do município de Paulínia), através da Técnica de Inibiçäo de Focos de Fluorescência Rápida. A resposta imune foi avaliada considerando o estado nutricional do animal e o número de vacinaçöes anteriores. A maioria dos cäes näo tinha título de 0,5 UI/ml após 12 meses, independentemente do estado nutricional, e a resposta humoral ao reforço vacinal mostrou-se melhor em cäes com duas ou mais vacinaçöes prévias. Säo discutidos o referencial de 0,5 UI/ml como título protetor para a espécie canina e a influência do estado nutricional e condiçäo de saúde do animal como responsável pela resposta imune humoral


Assuntos
Vacina Antirrábica/imunologia , Relação Dose-Resposta Imunológica , Raiva/epidemiologia , Fenômenos Fisiológicos da Nutrição Animal , Programas de Imunização/veterinária
13.
Rev. Inst. Med. Trop. Säo Paulo ; 37(3): 187-90, maio-jun. 1995.
Artigo em Inglês | LILACS | ID: lil-154356

RESUMO

Estudou-se a cinetica de anticorpos anti-Toxocara em camundongos BALB/c infectados experimentalmente segundo tres esquemas: Grupo I (GI): 25 camundongos infectados com dose unica de 200 ovos embrionados de T. canis; grupo II (GII): 25 camundongos infectados com 150 ovos embrionados de T. canis, divididos em tres doses de 50 ovos, administrados no 1§, 5§ e 8§ dias; grupo III (GIII): 25 camundongos infectados com 150 ovos embrionados de T. canis, administrados em tres doses de 50 ovos no 1§, 14§ e 28§ dias...


Assuntos
Animais , Ratos , Toxocara/metabolismo , Toxocaríase/imunologia , Ensaio de Imunoadsorção Enzimática , Formação de Anticorpos/imunologia , Larva Migrans Visceral/imunologia
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