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Mechanism of activation for transcription factor PhoB suggested by different modes of dimerization in the inactive and active states.

ABSTRACT: Response regulators (RRs), which undergo phosphorylation/dephosphorylation at aspartate residues, are highly prevalent in bacterial signal transduction. RRs typically contain an N-terminal receiver domain that regulates the activities of a C-terminal DNA binding domain in a phosphorylation-dependent manner. We present crystallography and solution NMR data for the receiver domain of Escherichia coli PhoB which show distinct 2-fold symmetric dimers in the inactive and active states. These structures, together with the previously determined structure of the C-terminal domain of PhoB bound to DNA, define the conformation of the active transcription factor and provide a model for the mechanism of activation in the OmpR/PhoB subfamily, the largest group of RRs. In the active state, the receiver domains dimerize with 2-fold rotational symmetry using their alpha4-beta5-alpha5 faces, while the effector domains bind to DNA direct repeats with tandem symmetry, implying a loss of intramolecular interactions.

SUBMITTER: Bachhawat P

PROVIDER: S-EPMC3685586 | biostudies-literature | 2005 Sep

REPOSITORIES: biostudies-literature

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Mechanism of activation for transcription factor PhoB suggested by different modes of dimerization in the inactive and active states.

Bachhawat Priti P Swapna G V T GV Montelione Gaetano T GT Stock Ann M AM

Structure (London, England : 1993) 20050901 9

Response regulators (RRs), which undergo phosphorylation/dephosphorylation at aspartate residues, are highly prevalent in bacterial signal transduction. RRs typically contain an N-terminal receiver domain that regulates the activities of a C-terminal DNA binding domain in a phosphorylation-dependent manner. We present crystallography and solution NMR data for the receiver domain of Escherichia coli PhoB which show distinct 2-fold symmetric dimers in the inactive and active states. These structur ...[more]

PMID: 16154092

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Mechanism of activation for transcription factor PhoB suggested by different modes of dimerization in the inactive and active states.

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Mechanism of activation for transcription factor PhoB suggested by different modes of dimerization in the inactive and active states.

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