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Twisted or shifted? Fluorescence measurements of late intermediates in transcription initiation by T7 RNA polymerase.

ABSTRACT: T7 RNA polymerase undergoes dramatic structural rearrangements in the transition from initiation to elongation. Two models have been proposed for promoter-bound intermediates late in the transition. (i) A subset of promoter interactions are maintained through completion of the protein conformational (twist) change, and (ii) concerted movement (shift) of all promoter-binding elements away from the growing DNA-RNA hybrid leads to an open intermediate, with large-scale domain rotations deferred until after promoter release. Fluorescence resonance energy transfer measurements provide very strong support for the latter.

SUBMITTER: Turingan RS

PROVIDER: S-EPMC2546521 | biostudies-literature | 2007 May

REPOSITORIES: biostudies-literature

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Twisted or shifted? Fluorescence measurements of late intermediates in transcription initiation by T7 RNA polymerase.

Turingan Rosemary S RS Theis Karsten K Martin Craig T CT

Biochemistry 20070502 21

T7 RNA polymerase undergoes dramatic structural rearrangements in the transition from initiation to elongation. Two models have been proposed for promoter-bound intermediates late in the transition. (i) A subset of promoter interactions are maintained through completion of the protein conformational (twist) change, and (ii) concerted movement (shift) of all promoter-binding elements away from the growing DNA-RNA hybrid leads to an open intermediate, with large-scale domain rotations deferred unt ...[more]

PMID: 17472344

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