Análise do transcriptoma das glândulas venenosas do escorpião Tityus stigmurus

In Brazil, accidents with scorpions are considered of medical importance, not only by the high incidence, but also for the potentiality of the venom from some species in determining severe clinical conditions. Tityus stigmurus is a widely distributed scorpion species in Northeastern Brazil and known to cause severe human envenomations, inducing pain, hyposthesia, edema, erythema, paresthesia, headaches and vomiting. The present study uses a transcriptomic approach to characterize the molecular repertoire from the non-stimulated venom gland of Tityus stigmurus scorpion. A cDNA library was constructed and 540 clones were sequenced and grouped into 37 clusters, with more than one EST (expressed sequence tag) and 116 singlets. Forty-one percent of ESTs belong to recognized toxin-coding sequences, with antimicrobial toxins (AMP-like) the most abundant transcripts, followed by alfa KTx- like, beta KTx-like, beta NaTx-like and alfa NaTx-like. Our analysis indicated that 34% include other possible venom molecules , whose transcripts correspond to anionic peptides, hypothetical secreted peptides, metalloproteinases, cystein-rich peptides and lectins. Fifteen percent of ESTs are similar to cellular transcripts. Sequences without good matches corresponded to 11%. This investigation provides the first global view of cDNAs from Tityus stigmurus. This approach enables characterization of a large number of venom gland component molecules, which belong either to known or atypical types of venom peptides and proteins from the Buthidae family

Transcriptoma diferencial entre células-tronco mesenquimais humanas jovens e senescentes

Human mesenchymal stem cells (MSC) are powerful sources for cell therapy in regenerative medicine. The long time cultivation can result in replicative senescence or can be related to the emergence of chromosomal alterations responsible for the acquisition of tumorigenesis features in vitro. In this study, for the first time, the expression profile of MSC with a paracentric chromosomal inversion (MSC/inv) was compared to normal karyotype (MSC/n) in early and late passages. Furthermore, we compared the transcriptome of each MSC in early passages with late passages. MSC used in this study were obtained from the umbilical vein of three donors, two MSC/n and one MSC/inv. After their cryopreservation, they have been expanded in vitro until reached senescence. Total RNA was extracted using the RNeasy mini kit (Qiagen) and marked with the GeneChip ® 3 IVT Express Kit (Affymetrix Inc.). Subsequently, the fragmented aRNA was hybridized on the microarranjo Affymetrix Human Genome U133 Plus 2.0 arrays (Affymetrix Inc.). The statistical analysis of differential gene expression was performed between groups MSC by the Partek Genomic Suite software, version 6.4 (Partek Inc.). Was considered statistically significant differences in expression to p-value Bonferroni correction ˂.01. Only signals with fold change ˃ 3.0 were included in the list of differentially expressed. Differences in gene expression data obtained from microarrays were confirmed by Real Time RT-PCR. For the interpretation of biological expression data were used: IPA (Ingenuity Systems) for analysis enrichment functions, the STRING 9.0 for construction of network interactions; Cytoscape 2.8 to the network visualization and analysis bottlenecks with the aid of the GraphPad Prism 5.0 software. BiNGO Cytoscape pluggin was used to access overrepresentation of Gene Ontology categories in Biological Networks. The comparison between senescent and young at each group of MSC has shown that there is a difference in the expression parttern, being higher in the senescent MSC/inv group. The results also showed difference in expression profiles between the MSC/inv versus MSC/n, being greater when they are senescent. New networks were identified for genes related to the response of two of MSC over cultivation time. Were also identified genes that can coordinate functional categories over represented at networks, such as CXCL12, SFRP1, xvi EGF, SPP1, MMP1 e THBS1. The biological interpretation of these data suggests that the population of MSC/inv has different constitutional characteristics, related to their potential for differentiation, proliferation and response to stimuli, responsible for a distinct process of replicative senescence in MSC/inv compared to MSC/n. The genes identified in this study are candidates for biomarkers of cellular senescence in MSC, but their functional relevance in this process should be evaluated in additional in vitro and/or in vivo assays

Transcriptoma (RNA-seq) de laranja doce Valência (Citrus sinensis L. Osbeck) e Kumquat (Fortunella spp.) infectadas por Xanthomonas citri subsp. citri

Pós-graduação em Biociências e Biotecnologia Aplicadas à Farmácia - FCFAR

Caracterização do transcriptoma e genoma mitocondrial da formiga cortadeira Atta laevigata (Formicidae : Attini)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Transcriptoma do músculo longissimus dorsi de bovinos machos adultos da raça Nelore

Pós-graduação em Genética e Melhoramento Animal - FCAV

Estudo comparativo do genoma e do transcriptoma de Phyllosticta citricarpa (fase sexual Guignardia citricarpa) agente da Mancha Preta dos Citros e Phyllosticta capitalensis

Pós-graduação em Ciências Biológicas (Genética) - IBB

Transcriptoma da interação de tangerina satsuma (Citrus unshiu) e laranja doce Hamlin (Citrus sinensis) infectadas com Xanthomonas citri subsp. citri, agente causal do cancro cítrico

Pós-graduação em Agronomia (Genética e Melhoramento de Plantas) - FCAV

Análise do transcriptoma de folhas de cana-de-açúcar submetidas à prolongada limitação hídrica usando RNA-Seq

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise do transcriptoma das glândulas venenosas do escorpião Tityus stigmurus

In Brazil, accidents with scorpions are considered of medical importance, not only by the high incidence, but also for the potentiality of the venom from some species in determining severe clinical conditions. Tityus stigmurus is a widely distributed scorpion species in Northeastern Brazil and known to cause severe human envenomations, inducing pain, hyposthesia, edema, erythema, paresthesia, headaches and vomiting. The present study uses a transcriptomic approach to characterize the molecular repertoire from the non-stimulated venom gland of Tityus stigmurus scorpion. A cDNA library was constructed and 540 clones were sequenced and grouped into 37 clusters, with more than one EST (expressed sequence tag) and 116 singlets. Forty-one percent of ESTs belong to recognized toxin-coding sequences, with antimicrobial toxins (AMP-like) the most abundant transcripts, followed by alfa KTx- like, beta KTx-like, beta NaTx-like and alfa NaTx-like. Our analysis indicated that 34% include other possible venom molecules , whose transcripts correspond to anionic peptides, hypothetical secreted peptides, metalloproteinases, cystein-rich peptides and lectins. Fifteen percent of ESTs are similar to cellular transcripts. Sequences without good matches corresponded to 11%. This investigation provides the first global view of cDNAs from Tityus stigmurus. This approach enables characterization of a large number of venom gland component molecules, which belong either to known or atypical types of venom peptides and proteins from the Buthidae family

Transcriptoma diferencial entre células-tronco mesenquimais humanas jovens e senescentes

Human mesenchymal stem cells (MSC) are powerful sources for cell therapy in regenerative medicine. The long time cultivation can result in replicative senescence or can be related to the emergence of chromosomal alterations responsible for the acquisition of tumorigenesis features in vitro. In this study, for the first time, the expression profile of MSC with a paracentric chromosomal inversion (MSC/inv) was compared to normal karyotype (MSC/n) in early and late passages. Furthermore, we compared the transcriptome of each MSC in early passages with late passages. MSC used in this study were obtained from the umbilical vein of three donors, two MSC/n and one MSC/inv. After their cryopreservation, they have been expanded in vitro until reached senescence. Total RNA was extracted using the RNeasy mini kit (Qiagen) and marked with the GeneChip ® 3 IVT Express Kit (Affymetrix Inc.). Subsequently, the fragmented aRNA was hybridized on the microarranjo Affymetrix Human Genome U133 Plus 2.0 arrays (Affymetrix Inc.). The statistical analysis of differential gene expression was performed between groups MSC by the Partek Genomic Suite software, version 6.4 (Partek Inc.). Was considered statistically significant differences in expression to p-value Bonferroni correction ˂.01. Only signals with fold change ˃ 3.0 were included in the list of differentially expressed. Differences in gene expression data obtained from microarrays were confirmed by Real Time RT-PCR. For the interpretation of biological expression data were used: IPA (Ingenuity Systems) for analysis enrichment functions, the STRING 9.0 for construction of network interactions; Cytoscape 2.8 to the network visualization and analysis bottlenecks with the aid of the GraphPad Prism 5.0 software. BiNGO Cytoscape pluggin was used to access overrepresentation of Gene Ontology categories in Biological Networks. The comparison between senescent and young at each group of MSC has shown that there is a difference in the expression parttern, being higher in the senescent MSC/inv group. The results also showed difference in expression profiles between the MSC/inv versus MSC/n, being greater when they are senescent. New networks were identified for genes related to the response of two of MSC over cultivation time. Were also identified genes that can coordinate functional categories over represented at networks, such as CXCL12, SFRP1, xvi EGF, SPP1, MMP1 e THBS1. The biological interpretation of these data suggests that the population of MSC/inv has different constitutional characteristics, related to their potential for differentiation, proliferation and response to stimuli, responsible for a distinct process of replicative senescence in MSC/inv compared to MSC/n. The genes identified in this study are candidates for biomarkers of cellular senescence in MSC, but their functional relevance in this process should be evaluated in additional in vitro and/or in vivo assays

Análise transcriptômica da interação mamoeiro-Papaya Meleira Virus

O mamoeiro (Carica papaya L.) é uma das fruteiras mais cultivadas nas regiões tropicais e subtropicais do mundo. O Brasil faz parte do grupo dos países que mais produzem e exportam mamão no mundo. O Espírito Santo e a Bahia são responsáveis por mais de 70% da área brasileira produtora deste fruto. Porém, doenças causadas por microrganismos infecciosos afetam de modo considerável sua produção. Entre as principais doenças, destaca-se a meleira do mamoeiro, causada pelo Papaya meleira virus (PMeV), que ainda não possui uma cultivar resistente. Interessantemente os sintomas somente são desencadeados após a frutificação. Os mecanismos moleculares envolvidos no desenvolvimento dos sintomas e na resposta de defesa da planta ao PMeV ainda não foram esclarecidos. Para entender os pontos chaves desta interação, que permitam o desenvolvimento de metodologias de melhoramento genético, um estudo transcriptômico foi abordado. A tecnologia RNA-seq foi usada para o sequenciamento do transcriptoma a partir de plantas com 3, 6 e 8 meses de idade após plantio, inoculadas e não inoculadas com o PMeV. Os genes diferencialmente expressos nos 3 tempos e nas duas condições foram preditos e analisados. Estas análises revelaram um padrão de expressão geral dos genes envolvidos nesta interação. Foram encontrados 21 genes com o perfil de expressão alterado nas plantas inoculadas exclusivamente nos seis meses de idade. Destes, 8 genes envolvidos em processos de respostas de defesa e morte celular, resposta ao estresse e resposta ao estímulo biótico e abiótico foram reprimidos; enquanto os demais (13 genes), envolvidos principalmente em processos metabólicos primários, biogêneses, diferenciação e ciclo celular, comunicação e crescimento celular, bem como processos envolvidos em reprodução, e desenvolvimento da floração, foram superexpressos. Estes resultados sugerem que, aos seis meses de idade, a planta é obrigada a alterar seu programa de expressão gênica, direcionando a resposta para os processos próprios do desenvolvimento, requeridos nesse estádio fisiológico, que primam sob a resposta ao estresse, fato que finalmente leva ao desenvolvimento dos sintomas.

Regulação epigenética de um gene de resposta a stress de frio em arroz (OsDREB1B)

O arroz (Oryza sativa L.) constitui a principal fonte de alimento para mais de metade da população mundial. O frio tem um grande impacto no desenvolvimento da planta de arroz com efeitos negativos ao nível da produtividade e economia mundial. Os mecanismos epigenéticos associados a alterações estruturais da cromatina estão envolvidos nos mecanismos de resposta das plantas a stresses abióticos. O foco do presente trabalho consistiu na compreensão da influência de fatores epigenéticos, nomeadamente de modificações de histonas, na regulação transcricional de um gene específico (OsDREB1B) envolvido na resposta de arroz ao stress de frio. O estudo da regulação epigenética deste gene envolveu a utilização de plantas de arroz com mutações em enzimas epigenéticas e drogas remodeladoras da cromatina. Neste trabalho mostramos que o gene OsDREB1B é induzido pelo stress de frio (4 °C) em todas os genótipos de arroz analisados, no entanto, a indução do gene em resposta ao stress de frio é maior em Nipponbare que em Dongjin. Nos genótipos que apresentam epimutações, nomeadamente o knockout de osdrm2 (DMT706) e de oshac704 (HAC704), o gene OsDREB1B é mais expresso que no respetivo genótipo selvagem (Dongjin), sendo que a indução da expressão em resposta ao frio foi maior em DMT706 do que em HAC704. A análise do padrão de marcas histónicas ao longo do promotor de OsDREB1B, através da imunoprecipitação da cromatina (ChIP) com anticorpos específicos, revelou que, em resposta ao frio (4ºC), Dongjin apresenta uma menor predominância da marca H3K9ac na região de -519 a -355 pares de bases (antes do ATG), enquanto que Nipponbare possui maior presença de H4K5ac na região de -280 a -121 pares de bases, sugerindo que a regulação epigenética de OsDREB1B seja influenciada pelo genótipo. No caso dos epi-mutantes (HAC704 e DMT706) registou-se um empobrecimento das marcas histónicas testadas sugerindo que a indução da expressão do OsDREB1B em reposta ao stress provocado pelo frio não depende necessariamente da presença de OsDRM2 nem de OsHAC704. Uma visão integrada da paisagem epigenética e do transcriptoma, perspetiva uma melhor compreensão dos mecanismos envolvidos na resposta da planta a condições ambientais adversas, abrindo novas linhas de trabalho no sentido de obter plantas mais tolerantes a fatores de stress.

Molecular regulation of flowering induction in Quercus suber

Dissertação de mestrado em Plant Molecular Biology, Biotechnology and Bioentrepeneurship

HOXA9 as a key regulator in glioma initiation, aggressiveness and response to therapy

Tese de Doutoramento em Ciências da Saúde

Estudos fisiológicos e moleculares durante a superação da dormência morfológica de sementes de Annona crassiflora

Pós-graduação em Agronomia (Agricultura) - FCA