Conservation of sequence in the internal transcribed spacers and 5.8S ribosomal RNA among geographically separated isolates of parasitic scuticociliates (Ciliophora, Orchitophryidae)

Abstract

Nucleotide sequence from the internal transcribed spacers (ITS1 and ITS2) and the 5.8s gene from the r~bosomal RNA gene cluster of isolates of the scuticociliate Orchitophrya stellarum from 4 asteroid hosts were compared. Surprisingly, these data (495 bp) were identical for 0. stellarum isolated from the testes of Astenas amurensis from Japan; Pisaster ochraceus from British Columbia, Canada; Asterias rubens from The Netherlands; and Astenas vulgaris from Prince Edward Island, Canada. These sequence data were compared to those from 3 scuticociliates which parasitise crustaceans: Mesanophrys pugettensis, M. chesapeakensis and Anophryoides haemophila. No difference was found in this region between the nucleotide sequence of M pugettensis and M. chesapeakensis The sequence of Mesanophrys spp. differed by 9 2 % in the ITS1 and 4.7 % in the ITS2 from that of 0. stellarum. The sequence from the ITS1 (135 bp) and ITS2 (233 bp) of A. haenlophila differed by 42 6 and 20.5% respectively from those of 0. stellarum. Therefore, nucleotide sequence of the ITS regions in these scuticociliates is highly conserved.

Association and distribution of the ciliate Orchitophrya stellarum with asteriid sea stars on the west coast of North America

“…Genetic analysis indicates that Orchitophrya stellarum is very similar throughout its range in the northern hemisphere (Goggin & Murphy 2000). Our SEM micrographs of O. stellarum ciliary tracts and the presence of caudal cilia indicate the similarity of O. stellarum associated with the gonopore region in the present study with this ciliate studied in detail during the parasite to free-living phase transition and from the parasitic phase of Leptasterias spp.…”

“…(Leighton et al 1991, Stickle et al 2001a, and in Japan, where it parasitizes Asterias amurensis (Byrne et al 1997(Byrne et al , 1998. Nucleotide sequence data of the internal transcribed spacers and the 5.8S gene in the ribosomal RNA gene cluster of O. stellarum from 4 species of asteriid hosts from the Atlantic and Pacific Oceans were identical (Goggin & Murphy 2000). The global dispersal of many free-living microbial eukaryote species (Finlay 2002) supports the observation of the lack of genetic differentiation in nucleotide sequences in O. stellarum due to their global dispersal.…”

An ITS-based phylogenetic framework for the genus Vorticella : finding the molecular and morphological gaps in a taxonomically difficult group

“…Amplification of the ITS region and a fragment of approximately 150 bp comprising part of the internal H4 region was accomplished according to protocols in [31,32]. Amplicons were cleaned by filtration using a QIAquick PCR Purification Kit (Qiagen Sciences, Germantown, MD, USA) and sequenced in both directions using an ABI 3730-XL DNA analyzer (Applied Biosystems, Foster City, CA, USA).…”

Molecular phylogeny of the family Vorticellidae (Ciliophora, Peritrichia) using combined datasets with a special emphasis on the three morphologically similar genera Carchesium, Epicarchesium and Apocarchesium

“…PCR cycling conditions for amplification of the SSU rRNA gene were as follows: 1 cycle of 94 uC for 1 min followed by 30 cycles of 94 uC for 15 s, 63 uC for 1.5 min and 72 uC for 2.5 min and 1 cycle of 72 uC for 5 min. The ITS1-5.8S-ITS2 region was amplified using the ITS-forward (59-GTTCCCCTTGAACGAGGAATTC-39) and ITSreverse (59-TACTGATATGCTTAAGTTCAGCGG-39) primers, which are complementary to conserved regions and encompass the 39 end of the SSU rRNA gene, the whole of the ITS1-5.8S-ITS2 region and the 59 end of the large subunit rRNA gene (Diggles & Adlard, 1997;Goggin & Murphy, 2000). Cycling parameters were as follows: 1 cycle of 94 uC for 1 min, 30 cycles of 94 uC for 15 s, 63 uC for 30 s and 72 uC for 1 min and 1 cycle of 72 uC for 5 min.…”