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1.
Mol Ecol ; 17(3): 854-66, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18179441

RESUMEN

The phylogeography of the lacertid lizard Gallotia atlantica from the small volcanic island of Lanzarote (Canary Islands) was analysed based on 1075 bp of mitochondrial DNA (mtDNA) sequence (partial cytochrome b and ND2) for 157 individuals from 27 sites (including three sites from neighbouring islets). Levels of sequence divergence were generally low, with the most distant haplotypes separated by only 14 mutational steps. MtDNA divergence appears to coincide with formation of the middle Pleistocene lowland that united formerly separate ancient islands to form the current island of Lanzarote, allowing rejection of a two-island model of phylogeographical structure. There was evidence of large-scale population expansion after island unification, consistent with the colonization of new areas. A nested clade phylogeographical analysis (NCPA) revealed significant phylogeographical structuring. Two-step and higher-level clades each had disjunct distributions, being found to the east and west of a common area with a north-south orientation that extends between coasts in the centre-east of the island (El Jable). Other clades were almost entirely restricted to the El Jable region alone. Bayesian Markov chain Monte Carlo analyses were used to separate ongoing gene flow from historical associations. These supported the NCPA by indicating recent (75,000-150,000 years ago) east-west vicariance across the El Jable region. Lava flows covered El Jable and other parts of the central lowland at this time and likely led to population extinctions and temporary dispersal barriers, although present-day evidence suggests some populations would have survived in small refugia. Expansion of the latter appears to explain the presence of a clade located between the eastern and western components of the disjunct clades. Direct relationships between mtDNA lineages and morphology were not found, although one of two morphological forms on the island has a disjunct distribution that is broadly concordant with east-west components of the phylogeographical pattern. This work demonstrates how recent volcanic activity can cause population fragmentation and thus shape genetic diversity on microgeographical scales.


Asunto(s)
ADN Mitocondrial/genética , Ecosistema , Lagartos/genética , Erupciones Volcánicas , Animales , Islas del Atlántico , Teorema de Bayes , Citocromos b/química , Citocromos b/genética , ADN Mitocondrial/química , Variación Genética , Haplotipos/genética , Cadenas de Markov , Método de Montecarlo , NADH Deshidrogenasa/química , NADH Deshidrogenasa/genética , Filogenia , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN
2.
Mol Ecol Resour ; 11(3): 586-9, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21457476

RESUMEN

This article documents the addition of 238 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Alytes dickhilleni, Arapaima gigas, Austropotamobius italicus, Blumeria graminis f. sp. tritici, Cobitis lutheri, Dendroctonus ponderosae, Glossina morsitans morsitans, Haplophilus subterraneus, Kirengeshoma palmata, Lysimachia japonica, Macrolophus pygmaeus, Microtus cabrerae, Mytilus galloprovincialis, Pallisentis (Neosentis) celatus, Pulmonaria officinalis, Salminus franciscanus, Thais chocolata and Zootoca vivipara. These loci were cross-tested on the following species: Acanthina monodon, Alytes cisternasii, Alytes maurus, Alytes muletensis, Alytes obstetricans almogavarii, Alytes obstetricans boscai, Alytes obstetricans obstetricans, Alytes obstetricans pertinax, Cambarellus montezumae, Cambarellus zempoalensis, Chorus giganteus, Cobitis tetralineata, Glossina fuscipes fuscipes, Glossina pallidipes, Lysimachia japonica var. japonica, Lysimachia japonica var. minutissima, Orconectes virilis, Pacifastacus leniusculus, Procambarus clarkii, Salminus brasiliensis and Salminus hilarii.


Asunto(s)
Bases de Datos Genéticas , Hongos/clasificación , Repeticiones de Microsatélite , Plantas/clasificación , Animales , Hongos/genética , Datos de Secuencia Molecular , Plantas/genética , Análisis de Secuencia de ADN
3.
Mol Ecol Resour ; 9(1): 274-7, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21564625

RESUMEN

We describe nine polymorphic tetranucleotide microsatellite loci from the starfish, Asterina gibbosa. Loci were isolated from a partial genomic library that had been enriched for AAAC repeat sequences. Number of alleles per locus ranged from two to 14 in a sample of 85 individuals from three populations (two from Spain and one from the UK). Observed and expected heterozygosities per population ranged from 0.000 to 0.400 and from 0.040 to 0.784, respectively. All loci presented significant heterozygote deficits in one or more populations. Eight of these loci were amplified and variable in A. pancerii and A. phylactica. These loci will be used to study population structure in A. gibbosa.

4.
Mol Ecol Resour ; 8(3): 631-3, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-21585854

RESUMEN

Eight microsatellite loci are described for the lizard Psammodromus algirus, a species widely used as a model in behavioural and ecological studies. All loci were highly polymorphic (six alleles or more per locus) in a sample of 24 individuals from a single site near Navacerrada (central Spain). Observed heterozygosity ranged from 0.29 to 0.96. These markers will be used to study mating strategies and determinants of reproductive success in this species.

5.
Mol Ecol Resour ; 8(3): 666-8, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-21585865

RESUMEN

The scincid lizard Chalcides sexlineatus is endemic to the island of Gran Canaria, within which it shows a pronounced phylogeographical pattern. Understanding the maintenance of this pattern requires knowledge of nuclear DNA structuring. Eleven polymorphic tetranucleotide microsatellite loci were isolated from a library constructed from genomic DNA enriched for AAAG repeat sequence. The number of alleles per locus ranged from 12 to 19, and expected heterozygosities spanned from 0.738 to 0.933 (n = 30). The majority of these could be cross-amplified in other endemic Canarian Chalcides. The loci will be used to investigate gene flow between the principal mitochondrial clades within C. sexlineatus.

6.
Eye (Lond) ; 2 ( Pt 4): 409-11, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3253132

RESUMEN

The Volk +90 dioptre lens offers a stereoscopic, wide-field (60 degrees) retinal view without the disadvantage of contact funduscopy. Used in conjunction with the slit-lamp, the lens gives a bright, inverted, magnified image of the posterior segment. Its uses in the diagnosis of posterior pole pathology, detailed examination of the optic disc and fundus photography are well established.


Asunto(s)
Lentes , Fotocoagulación/instrumentación , Retina/cirugía , Enfermedades de la Retina/cirugía , Humanos , Fotocoagulación/métodos
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