Filogeografia do gênero Rhizoprionodon (Elasmobranchii, Carcharhinformes) no Atlântico Ocidental utilizando marcadores moleculares do DNA mitocondrial

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

Aedes aegypti on Madeira Island (Portugal): genetic variation of a recently introduced dengue vector

The increasing population of Aedes aegypti mosquitoes on Madeira Island (Portugal) resulted in the first autochthonous dengue outbreak, which occurred in October 2012. Our study establishes the first genetic evaluation based on the mitochondrial DNA (mtDNA) genes [cytochrome oxidase subunit I (COI) and NADH dehydrogenase subunit 4 (ND4)] and knockdown resistance ( kdr ) mutations exploring the colonisation history and the genetic diversity of this insular vector population. We included mosquito populations from Brazil and Venezuela in the analysis as putative geographic sources. The Ae. aegyptipopulation from Madeira showed extremely low mtDNA genetic variability, with a single haplotype for COI and ND4. We also detected the presence of two important kdr mutations and the quasi-fixation of one of these mutations (F1534C). These results are consistent with a unique recent founder event that occurred on the island of Ae. aegyptimosquitoes that carry kdr mutations associated with insecticide resistance. Finally, we also report the presence of the F1534C kdr mutation in the Brazil and Venezuela populations. To our knowledge, this is the first time this mutation has been found in South American Ae. aegypti mosquitoes. Given the present risk of Ae. aegypti re-invading continental Europe from Madeira and the recent dengue outbreaks on the island, this information is important to plan surveillance and control measures.

Identification of blood meal sources of Lutzomyia longipalpis using polymerase chain reaction-restriction fragment length polymorphism analysis of the cytochrome B gene

An analysis of the dietary content of haematophagous insects can provide important information about the transmission networks of certain zoonoses. The present study evaluated the potential of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of the mitochondrial cytochrome B (cytb) gene to differentiate between vertebrate species that were identified as possible sources of sandfly meals. The complete cytb gene sequences of 11 vertebrate species available in the National Center for Biotechnology Information database were digested with Aci I, Alu I, Hae III and Rsa I restriction enzymes in silico using Restriction Mapper software. The cytb gene fragment (358 bp) was amplified from tissue samples of vertebrate species and the dietary contents of sandflies and digested with restriction enzymes. Vertebrate species presented a restriction fragment profile that differed from that of other species, with the exception of Canis familiaris and Cerdocyon thous. The 358 bp fragment was identified in 76 sandflies. Of these, 10 were evaluated using the restriction enzymes and the food sources were predicted for four: Homo sapiens (1), Bos taurus (1) and Equus caballus (2). Thus, the PCR-RFLP technique could be a potential method for identifying the food sources of arthropods. However, some points must be clarified regarding the applicability of the method, such as the extent of DNA degradation through intestinal digestion, the potential for multiple sources of blood meals and the need for greater knowledge regarding intraspecific variations in mtDNA.

Molecular Evaluation of Developmental Competence of Oocytes Collected In Vivo from Buffalo and Bovine Heifers during Winter and Summer

Buffaloes and bovines are polyestrous and seasonal or annual livestock, respectively, that show reduced fertility during heat stress. To investigate whether reduced fertility is related to oocyte competence in both species, immature oocytes from buffalo and bovine heifers were collected during winter and summer and subjected to molecular analyses. In each season, heifers of both species had their follicular wave emergence synchronized with a standard protocol (Ferreira et al., 2011). Before being subjected to ovum pick up (OPU), cutaneous (CT; degrees C) and rectal (RT; degrees C) temperatures and respiratory rate (RR; breaths/min) were measured. Oocytes' RNA was extracted to evaluate the expression of target genes related to mtDNA replication/transcription (PPARGC1A, TFAM and MT-CO1), apoptosis (BAX and BCL2) and HS (HSP90AA1 and HSPA1AB). ACTB, HIST1H2AG and GAPDH were initially chosen as housekeeping genes. In buffaloes, CT (35.0 +/- 0.4 vs 23.8 +/- 0.5), RT (38.7 +/- 0.1 vs 38.0 +/- 0) and RR (21.3 +/- 1.2 vs 15.4 +/- 1.1) were higher during summer than winter. However, in bovine heifers, RT (38.7 +/- 0.1 vs 38.6 +/- 0.1) and RR (44.8 +/- 1.5 vs 40.6 +/- 1.5) were similar in both seasons, while CT (31.6 +/- 0.3 vs 30.2 +/- 0.3) was increased during summer. Reduced expression of ACTB, HIST1H2AG and GAPDH was evidenced during summer, disqualifying them as housekeeping genes. Similarly, the expression of all target genes was reduced during summer in oocytes of both species. In summary, physiological responses to heat stress seem to be more intense in buffalo than bovine heifers. However, in both species, negative effects of heat stress upon oocyte quality occur at the molecular level and affects genes related to several biological functions.

Pseudoplatystoma metaense and P. orinocoense (Siluriformes: Pimelodidae) from the Orinoco basin, Venezuela: cytogenetic and molecular analyses

The genus Pseudoplatystoma includes catfish species distributed throughout the fresh waters of South America. These species are important fisheries resources and play a significant ecological role due to their piscivorous and migratory habits. The taxonomy of this genus is still debated: traditionally, only three species have been recognised, but recently, this number was raised to eight. The validity of these eight morphospecies, however, was not confirmed by two subsequent molecular phylogenetic studies, which identified either five or four main clades. In this study, we focused on the two morphospecies restricted to the Orinoco basin, P. metaense and P. orinocoense, which have been assigned to either the same or different clades in previous studies. We carried out cytogenetic analyses to describe their unknown karyotypes and to look for cytotaxonomic markers. We also analysed their mitochondrial sequences in order to assign the sampled specimens to the previously identified molecular clades. The two presumptive species show similar karyotypes (2n=56, 42 biarmed and 14 uniarmed chromosomes) and cytogenetic features in terms of the constitutive heterochromatin distribution and the number and location of minor and major ribosomal genes. Thus, no species-specific chromosome markers could be identified. The analysis of cytochrome b and cytochrome oxidase I mitochondrial genes (carried out by retrieving all the mtDNA Pseudoplatystoma sequences available in GenBank) distributed the sampled specimens into two distinct molecular clades and confirmed the need to re-evaluate, by parallel morphological and molecular analyses, the monophyly of some lineages.

Investigation of the genetic diversity of domestic Capra hircus breeds reared within an early goat domestication area in Iran

Background: Iran is an area of particular interest for investigating goat diversity. Archaeological remains indicate early goat domestication (about 10 000 years ago) in the Iranian Zagros Mountains as well as in the high Euphrates valley and southeastern Anatolia. In addition, mitochondrial DNA data of domestic goats and wild ancestors (C. aegagrusor bezoar) suggest a pre-domestication management of wild populations in southern Zagros and central Iranian Plateau. In this study genetic diversity was assessed in seven Iranian native goat breeds, namely Markhoz, Najdi, Taleshi, Khalkhali, Naini, native Abadeh and Turki-Ghashghaei. A total of 317 animals were characterized using 14 microsatellite loci. Two Pakistani goat populations, Pahari and Teddy, were genotyped for comparison.Results: Iranian goats possess a remarkable genetic diversity (average expected heterozygosity of 0.671 across loci, 10.7 alleles per locus) mainly accounted for by the within-breed component (G(ST) = 5.9%). Positive and highly significant F-IS values in the Naini, Turki-Ghashghaei, Abadeh and Markhoz breeds indicate some level of inbreeding in these populations. Multivariate analyses cluster Iranian goats into northern, central and western groups, with the western breeds relatively distinct from the others. Pakistani breeds show some relationship with Iranian populations, even if their position is not consistent across analyses. Gene flow was higher within regions (west, north, central) compared to between regions but particularly low between the western and the other two regions, probably due to the isolating topography of the Zagros mountain range. The Turki-Ghashghaei, Najdi and Abadeh breeds are reared in geographic areas where mtDNA provided evidence of early domestication. These breeds are highly variable, located on basal short branches in the neighbor-joining tree, close to the origin of the principal component analysis plot and, although highly admixed, they are quite distinct from those reared on the western side of the Zagros mountain range.Conclusions: These observations call for further investigation of the nuclear DNA diversity of these breeds within a much wider geographic context to confirm or re-discuss the current hypothesis (based on maternal lineage data) of an almost exclusive contribution of the eastern Anatolian bezoar to the domestic goat gene pool.

The first assess of the haplotypes from COI gene sequences in species of spittlebugs (Cicadomorpha: Hemiptera) and aquatic true bugs (Gerromorpha and Nepomorpha: Hemiptera) in Brazil

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

Mitochondrial DNA control region diversity in a population from Espirito Santo state, Brazil

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

Genetic diversity and population structure of the New World screwworm fly from the Amazon region of Brazil

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

High Levels of Diversity Uncovered in a Widespread Nominal Taxon: Continental Phylogeography of the Neotropical Tree Frog Dendropsophus minutus

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

Single Origin of Sex Chromosomes and Multiple Origins of B Chromosomes in Fish Genus Characidium

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

Diversidade gênica no gênero Astyanax (Teleostei : Characidae) através da análise de PCR-RFLP de DNA mitocondrial

O gênero Astyanax é um dos mais abundantes e diversificados da família Characidae (subfamília Tetragonopterinae), com mais de 100 espécies nominais, estando amplamente distribuído na bacia do Alto rio Paraná. Esse gênero é caracterizado pela similaridade quanto à forma do corpo, além da alta variabilidade citogenética intra e interpopulações, sendo comum a ocorrência de espécies crípticas ou complexos de espécies. Devido à escassez de dados sobre genética molecular referentes a esse gênero, e a dificuldade na identificação taxonômica, fazse necessário um estudo utilizando marcadores moleculares que visem desenvolver métodos rápidos e eficientes para caracterização de espécies de Astyanax com base em análises de DNA. Em vista dessa necessidade, o presente trabalho teve como objetivo avaliar a eficiência da técnica de PCR-RFLP do gene mitocondrial Citocromo b na identificação e caracterização da variabilidade genética de cinco espécies do gênero Astyanax que ocorrem na bacia do Alto rio Paraná. O mtDNA das espécies alvo foi totalmente amplificado, num total de cerca de 1140 pares de bases (pb). As análises foram obtidas através dos haplótipos gerados com a digestão por três enzimas de restrição que clivam estes genes, sendo estas ALUI, BAMHI, e HPAII. Foram analisadas 2 populações de Astyanax paranae, A. altiparanae, A. fasciatus, A. bockmanni, e uma população de A. biotae, com amostragens variando entre 5 e 10 indivíduos de cada população. Como grupo externo foram analisadas duas populações de Astyanax ribeirae da bacia hidrográfica do rio Ribeira de Iguape. Ao final do trabalho foi possível a identificação de 4 das 6 espécies analisadas, sendo que as espécies mais divergentes são A. altiparanae e A. ribeirae, as espécies A. paranae + A. bockmanni e A. fasciatus + A. ribeirae são as mais fortemente relacionadas...(Resumo completo, clicar acesso eletrônico abaixo)

Análise de SNPs do DNA mitocondrial em indivíduos residentes no estado do Espírito Santo para aplicação na Identificação Humana

Pós-graduação em Biotecnologia - IQ

Análise da relação filogenética entre Triatoma carcavalloi Jurberg, Rocha; Lent, 1998; Triatoma circummaculata Stal, 1859; Triatoma klugi Carcavallo, Jurberg, Lent; Galvão, 2001 e Triatoma rubrovaria Blanchard, 1843 (Hemiptera, Reduviidae) baseada no sequenciamento de genes do DNA mitocondrial e nuclear

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

First identification of interspecies hybridization in the freshwater stingrays Potamotrygon motoro and P-falkneri (Myliobatiformes, Potamotrygonidae)

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