Search results for "MITOCHONDRIAL DNA"
showing 10 items of 259 documents
Populations, hybrids and the systematic concepts of species and subspecies in Chagas disease triatomine vectors inferred from nuclear ribosomal and m…
2009
In Chagas disease, triatomine vectors are the main target for control measures because of the absence of effective drugs. The broad usefulness of nuclear rDNA and mtDNA sequences explains why triatomine studies using these markers have increased so pronouncedly in recent years. This indicates the appropriateness of an updated review about these molecular markers, concentrating on aspects useful for research on Chagas disease vectors. A comparative analysis is presented on the efficiency, weight of their different characteristics, limitations and problems of each of the different DNA markers in the light of the results obtained in studies on populations, hybrids, subspecies and species of th…
Mitochondrial Dna Sequence Variation among Geographic Strains of Diamondback Moth (Lepidoptera: Plutellidae)
1997
We examined genetic variation among 6 geographic strains of diamondback moth, Plutella xylostella (L.), using 365 base pairs of the mitochondrial gene encoding cytochrome oxidase I (COI). No sequence variation was detected within 5 of the 6 strains; 1 strain contained 2 haplotypes that differed by a single base substitution (0.27%). Sequence differences between strains of diamondback moth from Hawaii, the Philippines, and Pennsylvania ranged from 0 to 0.82%. With one exception, base pair substitutions among strains resulted in synonymous codons and did not alter amino acid sequence. Genetic divergence between strains of diamondback moth was not correlated with geographic distances between t…
12S rRNA mitochondrial gene as marker to trace Sicilian mono-species dairy products
2016
Abstract For a rapid, specific and sensitive identification of cows', ewes' and goats' milk in mono-species Sicilian dairy products, species-specific duplex-PCR protocol was applied. DNA samples from blood and experimental cheeses of Sicilian autochthonous breeds were extracted to amplify the 12S rRNA (and part of 16S rRNA in case of Ovis aries ) mitochondrial species-specific gene fragment. The use of species-specific primers for Bos taurus , Capra hircus and Ovis aries species, after electrophoresis on agarose gel, yielded fragments of 256 bp, 326 bp and 172 bp, respectively. Amplification by duplex - PCR of DNA pools from two species showed detection thresholds of 0.1% of “contaminant” D…
Rapid characterization of wild and collection strains of the genus Zygosaccharomyces according to mitochondrial DNA patterns
1997
Several wild and collection strains of the genus Zygosaccharomyces were characterized using a rapid and simple method of restriction analysis of mitochondrial DNA. Patterns obtained with three endonucleases (HaeIII, HinfI and RsaI) made it possible to differentiate each species and to identify the wild strains, isolated from the same spoiled concentrated must, as belonging to the species Z. rouxii. The HinfI restriction enzyme produced a strain-specific pattern which allowed us to recognize that the seven wild isolates belonged to only three strains.
Congruence in genetic markers used to describe Mediterranean and Atlantic populations of European hake (Merluccius merluccius L. 1758)
2004
Summary Eight samples of the hake, Merluccius merluccius L., from the Mediterranean basin (370 fishes total) and one from the Atlantic ocean (50 fishes) were analysed in order to assess genetic variability and describe genetic population structure. Five polymorphic protein coding loci were scored (ADH*, PGI-1*, PGI-2*, PGM* and SOD-1*) in eight samples, together with a haplotype variation of four samples, obtained from polymerase chain reaction/restriction fragment length polymorphism (PCR–RFLP) analysis on the mitochondrial DNA control region. The average value for observed heterozygosity was typically higher than expected (showing an excess of heterozygotes among the samples) whereas the …
Rapid characterization of four species of the Saccharomyces sensu stricto complex according to mitochondrial DNA patterns
1994
Several strains of the four sibling species of the genus Saccharomyces (S. bayanus, S. cerevisiae, S. paradoxus, and S. pastorianus) were characterized by using a rapid and simple method of restriction analysis of mitochondrial DNA. Patterns obtained with four-cutter endonucleases (such as AluI, DdeI, HinfI, and RsaI) made it possible to differentiate each species. S. cerevisiae and S. paradoxus presented a greater number of large fragments than S. pastorianus and S. bayanus with all the assay enzymes. With AluI and DdeI, species-specific bands clearly permitted differentiation between S. pastorianus and S. bayanus. To test the resolution of this method, wild Saccharomyces strains were anal…
Modern taurine cattle descended from small number of near-eastern founders.
2012
Archaeozoological and genetic data indicate that taurine cattle were first domesticated from local wild ox (aurochs) in the Near East some 10,500 years ago. However, while modern mitochondrial DNA (mtDNA) variation indicates early Holocene founding event(s), a lack of ancient DNA data from the region of origin, variation in mutation rate estimates, and limited application of appropriate inference methodologies have resulted in uncertainty on the number of animals first domesticated. A large number would be expected if cattle domestication was a technologically straightforward and unexacting region-wide phenomenon, while a smaller number would be consistent with a more complex and challengin…
Interactions between the yeast mitochondrial and nuclear genomes: isogenic suppressive and hypersuppressive petites differ in their resistance to the…
1990
In a previous paper we have shown that the alkaloid lycorine inhibits growth of rho+, mit- and rho-, strains of Saccharomyces cerevisiae, whereas strains devoid of mitochondrial DNA (rho degrees) are resistant to more than 200 micrograms/ml of the alkaloid. In this report we show that hypersuppressive petites are almost as resistant as rho degrees mutants, whereas isogenic rho- petites, which have retained longer segments of the genome, are sensitive to the drug.
The molecular characterization of new types of Saccharomyces cerevisiae × S. kudriavzevii hybrid yeasts unveils a high genetic diversity
2012
New double- and triple-hybrid Saccharomyces yeasts were characterized using PCR-restriction fragment length polymorphism of 35 nuclear genes, located on different chromosome arms, and the sequencing of one nuclear and one mitochondrial gene. Most of these new hybrids were originally isolated from fermentations; however, two of them correspond to clinical and dietary supplement isolates. This is the first time that the presence of double-hybrid S. cerevisiae×S. kudriavzevii in non-fermentative substrates has been reported and investigated. Phylogenetic analysis of the MET6 nuclear gene confirmed the double or triple parental origin of the new hybrids. Restriction analysis of gene regions in …
Characterisation of four species of the genus Kluyveromyces by mitochondrial DNA restriction analysis
1997
Summary In the present work, we determine the relationships at the within-species level among strains of Kluyveromyces dobzhanskii, K. lactis, K. marxianus, and K. thermotolerans, through the restriction analysis of their mtDNAs. The three first species showed a high level of intraspecific mtDNA divergence, this polymorphism is correlated to the varieties or species defined according to the original taxonomy of the genus, which is in concordance with that shown by other phenotypic or genotypic markers codified for by the nuclear genome. In these species, the analysis of the relationships among strains based on mtDNA restriction data agrees with previous classifications based on morphologica…