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1.
2.
Data Brief ; 15: 517-521, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29085872

RESUMO

The data presented in this article are related to the research article entitled "Molecular adaptive convergence in the α-globin gene in subterranean octodontid rodents" (Tomasco et al., 2017) [1]. This article shows the nucleotide sequences of α-globin subunit gene of hemoglobin of several South American caviomorph rodents, including subterranean and fossorial species. These sequences are deposited in Genbank, with accession numbers ranging from MF169881 to MF169898. Of a total of 429 nucleotides analyzed (143 codons), 100 variable sites and 43 amino acid replacements were reported. In this article we also show the results of TreeSaap (Woolley et al., 2003) [2] and MEME (Murrell et al., 2012) [3], that identified some replacement changes as interesting for future studies of adaptive evolution in this large rodent radiation.

3.
Heredity (Edinb) ; 116(4): 372-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26696136

RESUMO

The genetic relationships between the Pacific and the Atlantic populations of marine coastal biota in Southern South America have been analyzed in few studies, most of them relying on a single mitochondrial locus. We analyzed 10 polymorphic microsatellite loci, isolated from a dinucleotide-enriched Eleginops maclovinus genomic library, in a total of 240 individuals (48 from each of 5 sampled sites: 2 Atlantic, 2 Pacific and 1 in Beagle Channel). The results were contrasted against a previous work on the same species with mitochondrial DNA (mtDNA). Observed heterozygosity within localities ranged from 0.85 to 0.88 with the highest overall number of alleles observed at the northernmost locality on the Pacific side (Concepción), but no clear geographic pattern arose from the data. On the other hand, the number of private alleles was negatively correlated with latitude (Spearman's rs test, P=0.017). Among-population variance was low but significant (1.35%; P<0.0001, analysis of molecular variance (AMOVA)) and low genetic differentiation between populations was observed (pairwise FST values ranged from 0 to 0.021). A Mantel test revealed a significant correlation between geographic distances and FST (r=0.56, P=0.047). This could be partially accounted by the Atlantic versus Pacific population differentiation detected in three different analyses (STRUCTURE, SAMOVA (Spatial Analysis of MOlecular VAriance) and a population phylogeny). The observed pattern is compatible with a history of separation into two glacial refugia that was better captured by the multilocus microsatellite data than by the mtDNA analysis.


Assuntos
Evolução Molecular , Genética Populacional , Perciformes/genética , Alelos , Animais , Teorema de Bayes , DNA Mitocondrial/genética , Fluxo Gênico , Geografia , Repetições de Microssatélites , Modelos Genéticos , Filogenia , Análise de Sequência de DNA , América do Sul
4.
J Fish Biol ; 82(5): 1641-58, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23639159

RESUMO

The dietary preferences of populations of whitemouth croaker Micropogonias furnieri, which commonly inhabit estuarine and oceanic environments of the south-western Atlantic Ocean, were investigated using stable-isotope analysis and digestive traits, and compared with previous genetic and morphometric surveys of this species. Isotopic and C:N-derived data suggested that individuals from coastal lagoons are the most differentiated from the remaining localities surveyed. In contrast, the analysis of the digestive traits did not show the same differentiation pattern. The overall correlation between isotopic, molecular and morphological variations suggests that genetic and phenotypic differences among populations are accompanied by differential resource use, supporting the idea that selective forces could be playing an important role in population differentiation.


Assuntos
Trato Gastrointestinal , Perciformes/anatomia & histologia , Perciformes/fisiologia , Animais , Isótopos de Carbono , Comportamento Alimentar , Preferências Alimentares , Isótopos de Nitrogênio , Uruguai
5.
Genet. mol. biol ; Genet. mol. biol;25(1): 37-41, 2002. tab
Artigo em Inglês | LILACS | ID: lil-324984

RESUMO

The allele frequencies of 10 microsatellite loci previously described for sheep as BM1314, BM6526, OarFCB128, OarHH64, OarCP20, OarHH47, OarFCB48, OarHH35, OarHH72 and BM2508 were estimated for the Uruguayan flocks. A representative sample of 101 individuals composed by the two predominant breeds (76 percent Corriedale and 24 percent Australian Merino) was used. The sample did not show a significant tendency towards substructuring, in spite of presenting some significantly different allele frequencies between races. The Corriedale sample presents three loci in which the presence of null alleles is possible. The markers were highly variable, showing between 7 and 15 alleles each. The Polymorphism Information Content Index ranged from 0.63 to 0.87 and the Exclusion Probability from 0.39 to 0.75 for a cumulative Exclusion Probability of 99.98 percent. These results suggest the effectiveness of this set of loci for testing genetic relatedness. This is the first report of microsatellite variation in Corriedale


Assuntos
Animais , Polimorfismo Genético , Repetições de Microssatélites/genética , Ovinos , Alelos , Reação em Cadeia da Polimerase
6.
Mol Biol Evol ; 18(9): 1643-53, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11504845

RESUMO

The Aldolase multigene family comprises three functional genes (A, B, and C) with tissue-specific expression regulated during ontogeny. DGGE analysis and nucleotide sequencing reveal a family of retropseudogenes of type A in species of MUS: Significant variation in rates of evolution of Aldolase A retropseudogenes is apparent. Our analyses demonstrate that (1) multiple events of retrotransposition are needed to account for the diversity of Aldolase A processed pseudogenes found in mice; (2) some of these sequences have undergone further duplication subsequent to the original retrotransposition event; (3) the patterns of nucleotide substitution are broadly comparable with previous estimates; and (4) estimates of rates of divergence for this array of sequences are up to four times higher than those reported in the literature.


Assuntos
Frutose-Bifosfato Aldolase/genética , Dados de Sequência Molecular , Pseudogenes/genética , Animais , DNA/química , DNA/genética , Eletroforese/métodos , Evolução Molecular , Duplicação Gênica , Variação Genética , Camundongos , Camundongos Endogâmicos C3H , Filogenia , Análise de Sequência de DNA , Fatores de Tempo
7.
Mol Biol Evol ; 18(9): 1708-19, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11504851

RESUMO

We investigated the relationship between satellite copy number and chromosomal evolution in tuco-tucos (genus Ctenomys), a karyotypically diverse clade of rodents. To explore phylogenetic relationships among 23 species and 5 undescribed forms, we sequenced the complete mitochondrial cytochrome b genes of 27 specimens and incorporated 27 previously published sequences. We then used quantitative dot-blot techniques to assess changes in the copy number of the major Ctenomys satellite DNA (satDNA), named RPCS. Our analysis of the relationship between variation in copy number of RPCS and chromosomal changes employed a maximum-likelihood approach to infer the copy number of the satellite RPCS in the ancestors of each clade. We found that amplifications and deletions of RPCS were associated with extensive chromosomal rearrangements even among closely related species. In contrast, RPCS copy number stability was observed within clades characterized by chromosomal stability. This example reinforces the suspected role of amplification, deletion, and intragenomic movement of satDNA in promoting extensive chromosomal evolution.


Assuntos
Cromossomos/genética , DNA Satélite/genética , Roedores/genética , Animais , Aberrações Cromossômicas , Grupo dos Citocromos b/genética , DNA/química , DNA/genética , DNA Mitocondrial/química , DNA Mitocondrial/genética , Evolução Molecular , Amplificação de Genes , Deleção de Genes , Dosagem de Genes , Dados de Sequência Molecular , Filogenia , Roedores/classificação , Análise de Sequência de DNA , Especificidade da Espécie
8.
Mol Phylogenet Evol ; 9(1): 88-99, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9479698

RESUMO

Variation in the nucleotide sequence of the entire mitochondrial cytochrome b gene (1140 bp) was examined for 27 individuals representing 13 species of South American rodents of the genera Ctenomys, Octodontomys, Tympanoctomys, and Spalacopus. Representatives of the family Echimyidae, Euryzygomatomys and Mesomys, were used as outgroups to test the monophyly of the Octodontinae and Ctenomyinae. Relationships among species of tuco-tucos (genus Ctenomys) were also examined including representatives of the three described subgenera and the two sperm morphs. Reciprocal monophyly of the Octodontinae and Ctenomyinae is strongly supported. Several basal relationships among species of the genus Ctenomys are poorly resolved, suggesting the possibility of a hard polytomy due to a rapid and potentially simultaneous radiation early in the history of the genus. In other cases, clades within the Ctenomyinae previously identified on the basis of allozymes, chromosomes, parasites, or skull morphology were supported. Calibrations based on the fossil record suggest that the mitochondrial cytochrome b of these caviomorphs has evolved at a rapid rate, comparable to those proposed for Mus-Rattus, and three to four times higher than ungulate rates.


Assuntos
Evolução Molecular , Filogenia , Roedores/genética , Animais , Composição de Bases , Grupo dos Citocromos b/análise , Grupo dos Citocromos b/genética , DNA Mitocondrial/análise , DNA Mitocondrial/genética , Variação Genética , Dados de Sequência Molecular , Ratos
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