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DNA-induced unfolding of the thyroid hormone receptor ? A/B domain through allostery.

ABSTRACT: The A/B domains of nuclear receptors such as thyroid receptor ? (TR?) are considered to be conformationally flexible and can potentially adopt multiple structural conformations. We used intrinsic tryptophan fluorescence quenching and circular dichroism spectroscopy to characterize the unfolding of this A/B domain upon DNA binding to the contiguous DNA-binding domain (DBD). We propose that this allosteric change in A/B domain conformation can allow it to make the multiple interactions with distinct molecular factors of the transcriptional preinitiation complex. We further suggest that by influencing the affinity of the DBD for DNA, A/B domain can fine-tune the recognition of promotor DNA by TR?.

SUBMITTER: Fernandez EJ

PROVIDER: S-EPMC5458466 | biostudies-other | 2017 Jun

REPOSITORIES: biostudies-other

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DNA-induced unfolding of the thyroid hormone receptor α A/B domain through allostery.

Fernandez Elias J EJ Gahlot Vandna V Rodriguez Celeste C Amburn Jacob J

FEBS open bio 20170515 6

The A/B domains of nuclear receptors such as thyroid receptor α (TRα) are considered to be conformationally flexible and can potentially adopt multiple structural conformations. We used intrinsic tryptophan fluorescence quenching and circular dichroism spectroscopy to characterize the unfolding of this A/B domain upon DNA binding to the contiguous DNA-binding domain (DBD). We propose that this allosteric change in A/B domain conformation can allow it to make the multiple interactions with distin ...[more]

PMID: 28593140

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