RESUMO
The genus Ancyrocephalus sensu lato is a large assemblage of species of dactylogyrid monopisthocotyleans without clear taxonomic boundaries. Despite an urgent need for revision, only three representatives of this taxon have been molecularly characterised so far. We found specimens of Ancyrocephalus curtus, a previously non-genotyped species, in gills of Perccottus glenii caught in the River Syumnyur, Amur Basin, Russia. The aim of this study was to assess the phylogenetic position of this parasite using partial sequences of 28S rRNA gene. In the phylogenetic tree, A. curtus appeared as a sister taxon to the dactylogyrine genus Gobioecetes. The new molecular evidence supports the hypothesis about the non-monophyletic status of Ancyrocephalus sensu lato.
Assuntos
Doenças dos Peixes , Brânquias , Perciformes , Filogenia , RNA Ribossômico 28S , Animais , Doenças dos Peixes/parasitologia , Brânquias/parasitologia , Perciformes/parasitologia , RNA Ribossômico 28S/genética , Federação Russa , Rios/parasitologia , Infecções por Trematódeos/parasitologia , Infecções por Trematódeos/veterinária , Platelmintos/classificação , Platelmintos/genética , Platelmintos/isolamento & purificação , DNA de Helmintos/genética , Trematódeos/genética , Trematódeos/classificação , Trematódeos/isolamento & purificação , DNA Ribossômico/genética , Análise de Sequência de DNARESUMO
A new DNA repair gene from fission yeast Schizosaccharomyces pombe rlp1+ (RecA-like protein) has been identified. Rlp1 shows homology to RecA-like proteins, and is the third S. pombe Rad51 paralog besides Rhp55 and Rhp57. The new gene encodes a 363 aa protein with predicted Mr of 41,700 and has NTP-binding motif. The rlp1Delta mutant is sensitive to methyl methanesulfonate (MMS), ionizing radiation (IR), and camptothecin (CPT), although to a lesser extent than the deletion mutants of rhp55+ and rhp51+ genes. In contrast to other recombinational repair mutants, the rlp1Delta mutant does not exhibit sensitivity to UV light and mitomycin C (MMC). Mitotic recombination is moderately reduced in rlp1 mutant. Epistatic analysis of MMS and IR-sensitivity of rlp1Delta mutant indicates that rlp1+ acts in the recombinational pathway of double-strand break (DSB) repair together with rhp51+, rhp55+, and rad22+ genes. Yeast two-hybrid analysis suggests that Rlp1 may interact with Rhp57 protein. We propose that Rlp1 have an accessory role in repair of a subset of DNA damage induced by MMS and IR, and is required for the full extent of DNA recombination and cell survival under condition of a replication fork collapse.