The world in a river? A preliminary analysis of the 16S rDNA variability of Tubifex species (Clitellata: Tubificidae) from the Lambro River
Articolo
Data di Pubblicazione:
2008
Citazione:
The world in a river? A preliminary analysis of the 16S rDNA variability of Tubifex species (Clitellata: Tubificidae) from the Lambro River / A. Crottini, R. Marotta, M. Barbuto, M. Casiraghi, M. Ferraguti. - In: MOLECULAR PHYLOGENETICS AND EVOLUTION. - ISSN 1055-7903. - 48:3(2008), pp. 1189-1203.
Abstract:
Tubifex tubifex Müller, 1774 is a cosmopolitan freshwater tubificid widely used as a model in ecotoxicology,
population dynamics and developmental biology. It is traditionally recognized as a polytypic species and in Lambro River (Milano, Northern Italy) it occurs in two of the three recognized forms, named ‘‘tubifex”
and ‘‘blanchardi”, alternatively considered as ecological forms or distinct species. To investigate the genetic differentiation of the populations occurring in the Lambro River we sequenced a fragment of the
16S rDNA mitochondrial gene. T. blanchardi, characterized by a low genetic diversity, was genetically segregated from the other sympatric T. tubifex. The ancestral state reconstruction was used to define the
morphological traits that support its distinctness. On the contrary, the other T. tubifex from the Lambro community, although morphologically indistinguishable, revealed an astonishing degree of genetic variability,
both between and within the three identified clades that proved to be genetically isolated. Using samples from the mixed Lambro River community and from other countries around the world we present
an overview of the species complex’ 16S rDNA variability. Our results show that the genetic variability did not sensibly increase widening the data set, suggesting that the Lambro River populations meet
the species’ worldwide genetic variability.
Tipologia IRIS:
01 - Articolo su periodico
Keywords:
16S rDNA; Ancestral state reconstruction; Genetic differentiation; Haplotype network; Lambro River; Phylogeny; Tubifex species complex
Elenco autori:
A. Crottini, R. Marotta, M. Barbuto, M. Casiraghi, M. Ferraguti
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