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Multiple origins of the symbioses in Paramecium bursaria.
- Source :
-
Protist [Protist] 2008 Jan; Vol. 159 (1), pp. 53-63. Date of Electronic Publication: 2007 Nov 01. - Publication Year :
- 2008
-
Abstract
- Many organisms have symbioses with photosynthetic algae as typified by corals, clams, lichens, and some protozoa. Paramecium bursaria contains green algal symbionts and this unicellular ciliate is a textbook example used for microscopic observation in junior high school science projects. We have determined molecular phylogenies for the green algal symbionts. The symbiotic algae are the main constituent of the Paramecium cytoplasm, and we have recognized a total of four species, of which two were newly discovered in the present study. One should be regarded genetically as Chlorella vulgaris, and it belongs phylogenetically to the Chlorella clade (Chlorellaceae, Trebouxiophyceae) as well as "American" and "European" groups, which we previously introduced. Their genetic dissimilarities are 0.50-0.83% in 18S rDNA comparisons, but those of the internal transcribed spacer 2 (ITS2) reach an unambiguous level (22.6-26.6%). These dissimilarities suggest that they are equivalent to discrete species derived from multiple origins as paramecian symbionts. Another newcomer was clearly separated from the Chlorellaceae, and this alga clustered with Coccomyxa spp. in ITS2 analyses. These symbiotic relations indicate multiple origins of symbionts.
- Subjects :
- Animals
Base Sequence
Chlorella classification
Chlorella genetics
Chlorella growth & development
DNA, Ribosomal chemistry
DNA, Ribosomal genetics
DNA, Ribosomal Spacer chemistry
DNA, Ribosomal Spacer genetics
Molecular Sequence Data
Nucleic Acid Conformation
Paramecium classification
Paramecium growth & development
Phylogeny
RNA, Ribosomal, 18S genetics
Sequence Analysis, DNA
Paramecium genetics
Symbiosis genetics
Subjects
Details
- Language :
- English
- ISSN :
- 1434-4610
- Volume :
- 159
- Issue :
- 1
- Database :
- MEDLINE
- Journal :
- Protist
- Publication Type :
- Academic Journal
- Accession number :
- 17936071
- Full Text :
- https://doi.org/10.1016/j.protis.2007.08.002