Caracterização das formas juvenis e adultas dos camarões-rosa Farfantepenaeus brasiliensis (Latrelle, 1917) e F. paulensis (Perez-Farfante, 1967) (Decapoda: Penaeidae) por meio de técnicas moleculares e morfologia comparativa

Pós-graduação em Ciências Biológicas (Zoologia) - IBB

Clonagem, expressão e purificação de três mutantes truncados da proteína LaRPA-1 de Leishmania amazonensis

A leishmaniose é uma doença que atinge milhões de pessoas no mundo e, de acordo com a FUNASA, está se espalhando por todas as regiões do Brasil. O tratamento desta zoonose é ineficaz, pois os fármacos utilizados apresentam muitos efeitos colaterais e colaboram com o aparecimento de parasitas e vetores resistentes. Portanto um maior conhecimento sobre a biologia molecular destes protozoários poderá facilitar o descobrimento de novas terapias e desenvolvimento de drogas antiparasitárias. O complexo telomérico é formado pela interação de DNA com proteínas, sendo que estas últimas podem também interagir entre si. A proteína RPA de eucariotos compreende um complexo trimérico subdividido em três subunidades. Este cumpre independentemente ou juntamente com outras proteínas diversas funções vitais para a célula, entre elas, auxiliar na manutenção dos telômeros e ajudar a recrutar a telomerase. Além disso, ela parece ser um dos principais componentes do complexo de proteínas que interagem com o terminal simples fita telomérico de protozoários tripanosomatídeos. Curiosamente, em Leishmania spp., as subunidades 2 e 3, ao contrário da subunidade 1 da RPA, não fazem parte do complexo telomérico. Portanto a LaRPA-1 pode apresentar comportamentos peculiares quando comparada a RPA dos outros eucariotos, e se tornar um importante alvo ao se estudar a biologia molecular do parasita. Este trabalho tem como objetivo clonar, expressar e purificar os três diferentes mutantes truncados da proteína LaRPA-1 para, futuramente, utilizar-se estas proteínas recombinantes como ligantes em ensaios de interação proteína:proteína, visando mapear possíveis sítios ou domínios na proteína LaRPA-1.O gene que codifica LaRPA-1 já encontrava-se clonado e sequenciado no laboratório de Telômeros da UNESP de Botucatu....(Resumo completo, clicar acesso eletrônico abaixo)

Análise da expressão gênica de pequenos RNAs derivados de tRNAs (tRFs) em plantas

Small non coding RNAs emerged as important characters in several biology aspects. Among then, the most studied are microRNAs (miRNAs) and short interfering RNAs (siRNAs), that regulate their target gene post-transcriptionally in plants, animals and RNAi pathway intermediates, respectively. Both of classes have similar biogenesis being processed by Dicer enzymes and subsequent association with Argonaute enzymes. In plants, miRNAs and siRNAs have important functions in development, genome integrity and biotic and abiotic stress responses. The advances in high-throughtput sequencing and in silico analisys provide the uncover of new small non coding RNAs classes, many of them with unknown functions and biogenesis. tRNA derived small RNAs (tRFs) are a small non coding RNA class, that have as precursor a tRNA molecule. These were uncovers in the last decade in many organisms and, recently, in plants. Recent works detected tRFs from different sizes, with different source portions of the mature tRNA molecule (5’ end; 3’ end, anti-codon loop) and some from the tRNA precursor (pre-tRNA), suggesting that may be a novel class of small RNA and not random degradation products. Works in humans showed that some tRFs are processed by the Dicer enzymes, have association with the Argonaute enzymes and cell differentiation, tumor appearance and gene silencing related functions. Works in Arabidopsis and pumpkin (Cucurbita maxima) showed, respectively, that the tRFs have nutritional stress response possible functions and long distance signaling function between source and drain tissues, and may affect the translation. The tRFs biogenesis in plants are, until now an unknown, absence information about it in the literature and its possible biological functions are few studied yet, making then interesting target for studies among the small non coding RNAs in plants

Filogeografia e estrutura populacional de Astyanax paranae (Pisces: Characidae) na Bacia do rio Paranapanema

Atualmente, crescentes esforços vêm sendo desenvolvidos no sentido de se caracterizar a ictiofauna Neotropical de riachos do ponto de vista taxonômico e sistemático, porém a estrutura genética destas populações ainda é pouco conhecida, sendo escassos os estudos sobre filogeografia dessa ictiofauna. Considerando que Astyanax paranae representa a única espécie do complexo scabripinnis na bacia do Alto rio Paraná, a ausência de dados moleculares populacionais e as evidências citogenéticas e morfológicas de que esta espécie não represente uma unidade monofilética, faz-se necessário um amplo estudo filogeográfico e filogenético em Astyanax paranae. O presente projeto teve como objetivo caracterizar a variabilidade genética em populações de Astyanax paranae e estabelecer as relações filogenéticas filogeográficas entre as linhagens mitocondriais na bacia do rio Paranapanema. As análises foram realizadas através da análise de sequências do DNA mitocondrial a partir do gene Citocromo B (cyt b) que foram completamente seqüenciados. Foram analisadas 8 populações de Astyanax paranae: 2 populações da bacia do rio Pardo, 1 Córrego Hortelã, 2 Véu de Noiva, Botucatu/SP; 4 populações da bacia do rio Tibagi, 1 população Maria da Serra/PR; 1 Ponta Grossa/PR, 1 Cambé/PR, 1 Castrolanda/PR; 1 população do rio Itapetiniga, rio Itapetininga, Itapetiniga/SP.; o número de indivíduos por população variou de 1 a 5. Como grupo externo foram analisados 1 população de Astyanax altiparanae com 3 indivíduos (Véu de Noiva pt2, Botucatu/SP); 1 população de Astyanax fasciatus com 5 indivíduos (região de Itapetiniga/SP) e 1 população de Astyanax bockmanni com 2 indivíduos (Véu de Noiva pt2, Botucatu/SP); num total de 39 indivíduos. Entre as...(Resumo completo, clicar acesso eletrônico abaixo)

Clonagem e caracterização do promotor de um gene com expressão em folha de Eucalipto (Eucalyptus grandis)

Uma das principais estratégias de ação da biotecnologia na área vegetal trata da produção de plantas geneticamente modificadas com transgenes de interesse. Entretanto, para garantir a correta expressão de tais transgenes em plantas de interesse agronômico e florestal, como é o caso do eucalipto, a identificação e caracterização de seqüências promotoras com padrões conhecidos de expressão gênica se fazem necessárias. Nesse contexto, o presente trabalho objetivou clonar e sequenciar a região promotora de um gene com expressão em folha de Eucalyptus grandis. Em seguida, um cassete de expressão contendo o gene repórter GUS sobre controle do referido promotor foi construído e introduzido em vetor binário. O referido cassete foi então inserido em agrobactéria visando a futura transformação de plantas modelo para a realização de estudos funcionais

Investigação de elementos de transposição em populações de Drosophila mojavensis e D. arizonae e seus híbridos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo da interação entre a via genética do microRNA156/squamosa promoter-binding protein-like e brassinosteróides durante o desenvolvimento de Arabidopsis thaliana

Pós-graduação em Ciências Biológicas (Genética) - IBB

DNA Barcoding em Utricularia (Lentibulariaceae)

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

Análise de diversidade e expressão de retrotransposons ativos em espécies de Coffea

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Origin and molecular organization of supernumerary chromosomes of Prochilodus lineatus (Characiformes, Prochilodontidae) obtained by DNA probes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Classical and molecular cytogenetic characterization of Agonostomus monticola, a primitive species of Mugilidae (Mugiliformes)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Multiple nucleolus organizer regions in Leptodactylus mystacinus (Amphibia, Anura) and comments on its systematic position in the L fuscus group based on cytogenetic and molecular analyses

Specimens of Leptodactylus mystacinus from Brazil were karyotyped with conventional and differential staining. The 2n = 22 karyotype is similar to that found for the majority of the Leptodactylus, the karyotypic conservatism also confirmed by the similarity of the replication banding patterns with those previously described. L. mystacinus has a small amount of C-banded heterochromatin, located mainly at the centromeres, although telomeric or interstitial bands have also been noticed. With DA/CMA(3) some chromosome regions showed slightly bright fluorescence, and with DA/DAPI, no particular AT-rich repetitive region was observed. Silver staining showed an extensive inter- and intraindividual variation in the number and position of Ag-positive regions, in 1p, 4p, 8p, 8q, and 11p. Nevertheless, FISH using rDNA probes confirmed only the signals on the short arms of chromosomes 4 and 8 as true NORs. The remaining silver stained regions are probably due to the heterochromatin with some affinity to the Ag-staining. Phylogenetic analysis based on partial cytochrome b sequence revealed that L. mystacinus forms a basal branch, so that the presence of multiple NORs in pairs 4 and 8 in this species indicates an autapomorphy.

Molecular phylogeny and karyotype differentiation in Paratelmatobius and Scythrophrys (Anura, Leptodactylidae)

Paratelmatobius and Scythrophrys are leptodactylid frogs endemic to the Brazilian Atlantic forest and their close phylogenetic relationship was recently inferred in an analysis that included Paratelmatobius sp. and S. sawayae. To investigate the interspecific relationships among Paratelmatobius and Scythrophrys species, we analyzed a mitochondrial region (approximately 2.4 kb) that included the ribosomal genes 12S and 16S and the tRNAval in representatives of all known localities of these genera and in 54 other species. Maximum parsimony inferences were done using PAUP* and support for the clades was evaluated by bootstrapping. A cytogenetic analysis using Giemsa staining, C-banding and silver staining was also done for those populations of Paratelmatobius not included in previous cytogenetic studies of this genus in order to assess their karyotype differentiation. Our results suggested Paratelmatobius and Scythrophrys formed a clade strongly supported by bootstrapping, which corroborated their very close phylogenetic relationship. Among the Paratelmatobius species, two clades were identified and corroborated the groups P. mantiqueira and P. cardosoi previously proposed based on morphological characters. The karyotypes of Paratelmatobius sp. 2 and Paratelmatobius sp. 3 described here had diploid chromosome number 2n = 24 and showed many similarities with karyotypes of other Paratelmatobius representatives. The cytogenetic data and the phylogenetic analysis allowed the proposal/corroboration of several hypotheses for the karyotype differentiation within Paratelmatobius and Scythrophrys. Namely the telocentric pair No. 4 represented a synapomorphy of P. cardosoi and Paratelmatobius sp. 2, while chromosome pair No. 5 with interstitial C-bands could be interpreted as a synapomorphy of the P. cardosoi group. The NOR-bearing chromosome No. 10 in the karyotype of P. poecilogaster was considered homeologous to chromosome No. 10 in the karyotype of Scythrophrys sp., chromosome No. 9 in the karyotype of Paratelmatobius sp. 1, chromosome No. 8 in the karyotypes of Paratelmatobius sp. 2 and of Paratelmatobius sp. 3, and chromosome No. 7 in the karyotype of P. cardosoi. A hypothesis for the evolutionary divergence of these NOR-bearing chromosomes, which probably involved events like gain in heteochromatin, was proposed.

Molecular characterization and relatedness of Haematobia irritans (horn fly) populations, by RAPD-PCR

Haematobia irritans is a hematophagous parasite of cattle that causes significant economic losses in many parts of the world, including Brazil. In the present work, one American and four Brazilian populations of this species were studied by Random Amplified Polymorpht DNA (RAPD) to assess basically genetic variability within and between populations. Ten different decamer random primers were employed in the genomic DNA amplification, yielding 117 fragments in the five H.. irritans populations. In Drosophila prosaltans, used as an outgroup, 81 fragments were produced. Forty-three of these fragments were shared by both species. Among the H. irritans samples, that from Rio Branco (Acre State, Brazil) produced the smallest numbers of fragments and polymorphic bands. This high genetic homogenity may be ascribed to its geographic origin (in the Northwest of Brazil), which causes high isolation and low gene flow, unlike the other Brazilian populations, from the South Central region, in which cattle trade is very intensive. Marker fragments (exclusive bands) detected in every sample enabled the population origin to be characterized, but they are also potentially useful for further approaches such as the putative origin of Brazilian populations from North America. Similarity indices [Nei & Li, 1979, Proc. Natl. Acad. Sci. USA 76: 5269-5273] and phylogenetic trees, rooted by using the outgroup and produced by the Phylogenetic Analysis using Parsimony (PAUP 4.0-Swofford, 2001) program showed the closest relationships between flies from Sao Jose do Rio Preto and Turiuba (both from São Paulo State, Brazil) while flies from the geographically distant Rio Branco showed the greatest differentiation relative to the others.

Molecular characterization and chromosomal localization of two families of satellite DNA in Prochilodus lineatus (Pisces, Prochilodontidae), a species with B chromosomes

Prochilodus lineatus, an abundant species in the Mogi-Guaçu river basin, represents a large part of the region's fishing potential. Karyotypic analyses based on classic cytogenetic techniques have revealed the presence of 54 metasubmetacentric type chromosomes, together with the occurrence of small supernumerary chromosomes with intra and interindividual variations. This paper describes the genomic organization of two families of satellite DNA in the P. lineatus genome. The chromosomal localization these two repetitive DNA families through fluorescence in situ hybridization (FISH) demonstrated that the SATH1 satellite DNA family, composed of approximately 900 bp, was located in the pericentromeric region of a group of chromosomes of the standard complement, as well as on all the B chromosomes. The SATH2 satellite family has a monomeric unit of 441 bp and was located in the pericentromeric regions of some chromosomes of the standard complement, but was absent in the B chromosomes. Double FISH analyses showed that these two families participate jointly in the pericentromeric organization of several chromosomes of this species. The data obtained in this study support the hypothesis that the B chromosomes derive from chromosomes of the standard complement, which are carriers of the SATH1 satellite DNA.