Differentiation of Two Very Similar Glaucomid Ciliate Morphospecies (Ciliophora, Tetrahymenida) by Fluorescence in Situ Hybridization with 18S rRNA Targeted Oligonucleotide Probes

Abstract

Conventional, morphological identification of ciliates and other protozoa needs considerable experience and often is difficult as various staining methods must be applied. New molecular techniques, such as fluorescence in situ hybridization (FISH) with gene probes, are powerful means to overcome this problem. As a test case, the morphology of two very similar, and thus difficult to differentiate ciliate morphospecies, Glaucoma scintillans and Glaucomides bromelicola, were compared. They were then distinguished by applying the Ciliate-FISH technique with a set of eight 18S rRNA targeted oligonucleotide probes, four of which have been developed for specific detection of G. scintillans. The remaining four probes were designed to detect G. bromelicola in order to prove probe specificities by binding to the homologous target region of the probes mentioned before. The tests resulted in a clear and easy differentiation of the two species by fluorescence signals of three of the four tested probe pairs. Thus, FISH techniques are very useful for the identification and detection of protozoa and might be of great help studying geographical distributions of known taxa.

Rare Freshwater Ciliate Paramecium chlorelligerum Kahl, 1935 and Its Macronuclear Symbiotic Bacterium “Candidatus Holospora parva”

“…COI and ITS1-5.8S-ITS2, molecular markers usually employed to investigate intraspecific diversity, did not show any difference in the populations as they were 100% identical. Surprisingly, evolutionary more conserved 18S rDNA presented a couple of mismatches (CBC), which could be suitable to design a population-specific FISH probe, as an alternative and faster method to discriminate strains within the same morphospecies [76, 77]. The same phenomenon, but less emphasized, was found also in other members of the genus Paramecium [46, 78], where intraspecific variability was higher in 18S rDNA sequence than in the usually less conserved markers.…”

Molecular Phylogeny and Taxonomy of a New Freshwater Hymenostomatid from Northeastern China, with the Establishment of a New Genus Anteglaucoma gen. n. (Protista, Ciliophora, Oligohymenophorea)

“…; Chung and Yao ; Corliss , ; Foissner et al. ; Fried and Foissner ; Kher et al. ; Klug ; Liu et al.…”

“…CILIATES of subclass Hymenostomatia are common inhabitants of terrestrial, fresh, and brackish water environments (Chantangsi et al 2007;Chung and Yao 2012;Corliss 1954Corliss , 1971Foissner et al 1994;Fried and Foissner 2007;Kher et al 2011;Klug 1968;Liu et al 2007;Mochizuki et al 2002;Peck 1978). They show similar living features, relatively simple body plans and relatively few morphological characters for species circumscription (Borden et al 1977;Corliss 1952Corliss , 1959Frankel 1960;Liu et al 2016a;McCoy 1975).…”

Detection and Quantification of Two Parasitic Ciliates Boveria labialis and Boveria subcylindrica (Ciliophora: Scuticociliatia) by Fluorescence in situ Hybridization

“…Molecular techniques, such as the fluorescence in situ hybridization (FISH), can overcome the drawbacks of the morphological method and yield prompt and accurate detection (Fried and Foissner 2007;Stoeck et al 2003;Zhan et al 2014). FISH with specific fluorochrome-labeled oligonucleotide probes is a staining technique that allows molecular identification of targeted organisms in mixed assemblages by means of a fluorescence microscopy.…”

“…Molecular techniques, such as the fluorescence in situ hybridization (FISH), can overcome the drawbacks of the morphological method and yield prompt and accurate detection (Fried and Foissner ; Stoeck et al. ; Zhan et al.…”