1. Three Group-I introns in 18S rDNA of Endosymbiotic Algae of Paramecium bursaria from Japan.
- Author
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Hoshina, Ryo, Kamako, Shin-Ichiro, and Imamura, Nobutaka
- Subjects
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INTRONS , *SPLIT genes , *GENES , *ENDOSYMBIOSIS , *PARAMECIUM , *PARAMECIIDAE , *SYNCHROTRONS - Abstract
In the nuclear encoded small subunit ribosomal DNA (18S rDNA) of symbiotic alga of Paramecium bursaria (F36 collected in Japan) possesses three intron-like insertions (Hoshina et al., unpubl. data, 2003). The present study confirmed these exact lengths and insertion sites by reverse transcription-PCR. Two of them were inserted at Escherichia coli 16S rRNA genic position 943 and 1512 that are frequent intron insertion positions, but another insertion position (nearly 1370) was the first finding. Their secondary structures suggested they belong to Group-I intron; one belongs to subgroup IE, others belong to subgroup IC 1. Similarity search indicated these introns are ancestral ones. [ABSTRACT FROM AUTHOR]
- Published
- 2004
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