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Structure of stem-loop IV of Tetrahymena telomerase RNA.

ABSTRACT: Conserved domains within the RNA component of telomerase provide the template for reverse transcription, recruit protein components to the holoenzyme and are required for enzymatic activity. Among the functionally essential domains in ciliate telomerase RNA is stem-loop IV, which strongly stimulates telomerase activity and processivity even when provided in trans. The NMR structure of Tetrahymena thermophila stem-loop IV shows a highly structured distal stem-loop linked to a conformationally flexible template-proximal region by a bulge that severely kinks the entire RNA. Through extensive structure-function studies, we identify residues that contribute to both these structural features and to enzymatic activity, with no apparent effect on the binding of TERT protein. We propose that the bending induced by the GA bulge and the flexibility of the template-proximal region allow positioning of the prestructured apical loop during the catalytic cycle.

SUBMITTER: Chen Y

PROVIDER: S-EPMC1500990 | biostudies-literature | 2006 Jul

REPOSITORIES: biostudies-literature

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Structure of stem-loop IV of Tetrahymena telomerase RNA.

Chen Yu Y Fender Jessica J Legassie Jason D JD Jarstfer Michael B MB Bryan Tracy M TM Varani Gabriele G

The EMBO journal 20060615 13

Conserved domains within the RNA component of telomerase provide the template for reverse transcription, recruit protein components to the holoenzyme and are required for enzymatic activity. Among the functionally essential domains in ciliate telomerase RNA is stem-loop IV, which strongly stimulates telomerase activity and processivity even when provided in trans. The NMR structure of Tetrahymena thermophila stem-loop IV shows a highly structured distal stem-loop linked to a conformationally fle ...[more]

PMID: 16778765

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Structural study of elements of Tetrahymena telomerase RNA stem-loop IV domain important for function.

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Structure of Tetrahymena telomerase reveals previously unknown subunits, functions, and interactions.

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Tetrahymena telomerase protein p65 induces conformational changes throughout telomerase RNA (TER) and rescues telomerase reverse transcriptase and TER assembly mutants.

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New models of Tetrahymena telomerase RNA from experimentally derived constraints and modeling.

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Multiple DNA-binding sites in Tetrahymena telomerase.

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