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Crystal structure of a self-spliced group II intron.

ABSTRACT: Group II introns are self-splicing ribozymes that catalyze their own excision from precursor transcripts and insertion into new genetic locations. Here we report the crystal structure of an intact, self-spliced group II intron from Oceanobacillus iheyensis at 3.1 angstrom resolution. An extensive network of tertiary interactions facilitates the ordered packing of intron subdomains around a ribozyme core that includes catalytic domain V. The bulge of domain V adopts an unusual helical structure that is located adjacent to a major groove triple helix (catalytic triplex). The bulge and catalytic triplex jointly coordinate two divalent metal ions in a configuration that is consistent with a two-metal ion mechanism for catalysis. Structural and functional analogies support the hypothesis that group II introns and the spliceosome share a common ancestor.

SUBMITTER: Toor N

PROVIDER: S-EPMC4406475 | biostudies-literature | 2008 Apr

REPOSITORIES: biostudies-literature

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Crystal structure of a self-spliced group II intron.

Toor Navtej N Keating Kevin S KS Taylor Sean D SD Pyle Anna Marie AM

Science (New York, N.Y.) 20080401 5872

Group II introns are self-splicing ribozymes that catalyze their own excision from precursor transcripts and insertion into new genetic locations. Here we report the crystal structure of an intact, self-spliced group II intron from Oceanobacillus iheyensis at 3.1 angstrom resolution. An extensive network of tertiary interactions facilitates the ordered packing of intron subdomains around a ribozyme core that includes catalytic domain V. The bulge of domain V adopts an unusual helical structure t ...[more]

PMID: 18388288

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