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Ribosomal RNA sequences and the diversity of symbiotic dinoflagellates (zooxanthellae).

ABSTRACT: Zooxanthellae are unicellular algae that occur as endosymbionts in many hundreds of common marine invertebrates. The issue of zooxanthella diversity has been difficult to address. Most zooxanthellae have been placed in the dinoflagellate genus Symbiodinium as one or several species that are not easily distinguished. We compared Symbiodinium and nonsymbiotic dinoflagellates using small ribosomal subunit RNA sequences. Surprisingly, small ribosomal subunit RNA diversity within the genus Symbiodinium is comparable to that observed among different orders of nonsymbiotic dinoflagellates. These data reinforce the conclusion that Symbiodinium-like zooxanthellae represent a collection of distinct species and provide a precedent for a molecular genetic taxonomy of the genus Symbiodinium.

SUBMITTER: Rowan R

PROVIDER: S-EPMC48924 | biostudies-other | 1992 Apr

REPOSITORIES: biostudies-other

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Ribosomal RNA sequences and the diversity of symbiotic dinoflagellates (zooxanthellae).

Rowan R R Powers D A DA

Proceedings of the National Academy of Sciences of the United States of America 19920401 8

Zooxanthellae are unicellular algae that occur as endosymbionts in many hundreds of common marine invertebrates. The issue of zooxanthella diversity has been difficult to address. Most zooxanthellae have been placed in the dinoflagellate genus Symbiodinium as one or several species that are not easily distinguished. We compared Symbiodinium and nonsymbiotic dinoflagellates using small ribosomal subunit RNA sequences. Surprisingly, small ribosomal subunit RNA diversity within the genus Symbiodini ...[more]

PMID: 1565660

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