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Fluorescence probing of T box antiterminator RNA: insights into riboswitch discernment of the tRNA discriminator base.

ABSTRACT: The T box transcription antitermination riboswitch is one of the main regulatory mechanisms utilized by Gram-positive bacteria to regulate genes that are involved in amino acid metabolism. The details of the antitermination event, including the role that Mg(2+) plays, in this riboswitch have not been completely elucidated. In these studies, details of the antitermination event were investigated utilizing 2-aminopurine to monitor structural changes of a model antiterminator RNA when it was bound to model tRNA. Based on the results of these fluorescence studies, the model tRNA binds the model antiterminator RNA via an induced-fit. This binding is enhanced by the presence of Mg(2+), facilitating the complete base pairing of the model tRNA acceptor end with the complementary bases in the model antiterminator bulge.

SUBMITTER: Means JA

PROVIDER: S-EPMC2789444 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature

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Fluorescence probing of T box antiterminator RNA: insights into riboswitch discernment of the tRNA discriminator base.

Means John A JA Simson Crystal M CM Zhou Shu S Rachford Aaron A AA Rack Jeffrey J JJ Hines Jennifer V JV

Biochemical and biophysical research communications 20090913 4

The T box transcription antitermination riboswitch is one of the main regulatory mechanisms utilized by Gram-positive bacteria to regulate genes that are involved in amino acid metabolism. The details of the antitermination event, including the role that Mg(2+) plays, in this riboswitch have not been completely elucidated. In these studies, details of the antitermination event were investigated utilizing 2-aminopurine to monitor structural changes of a model antiterminator RNA when it was bound ...[more]

PMID: 19755116

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