The p23 Molecular Chaperone and GCN5 Acetylase Jointly Modulate Protein-DNA Dynamics and Open Chromatin Status

Department of Cell and Developmental Biology, University of Illinois, Urbana-Champaign, 601 S. Goodwin Avenue, Urbana, IL 61801, USA.
Molecular cell (Impact Factor: 14.02). 09/2012; 48(3). DOI: 10.1016/j.molcel.2012.08.026
Source: PubMed


Cellular processes function through multistep pathways that are reliant on the controlled association and disassociation of sequential protein complexes. While dynamic action is critical to propagate and terminate work, the mechanisms used to disassemble biological structures are not fully understood. Here we show that the p23 molecular chaperone initiates disassembly of protein-DNA complexes and that the GCN5 acetyltransferase prolongs the dissociated state through lysine acetylation. By modulating the DNA-bound state, we found that the conserved and essential joint activities of p23 and GCN5 impacted transcription factor activation potential and response time to an environmental cue. Notably, p23 and GCN5 were required to maintain open chromatin regions along the genome, indicating that dynamic protein behavior is a critical feature of various DNA-associated events. Our data support a model in which p23 and GCN5 regulate diverse multistep pathways by controlling the longevity of protein-DNA complexes.

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Available from: Brian C Freeman, May 21, 2014
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    • "The ability of HDAC1 to foster the free state of HSF1 might explain its genetic relationship with the p23 chaperone [16]. Previously, we found that GCN5 maintains HSF1 DNA separation after p23 releases HSF1 from DNA [13]. To test whether HDAC1 shares a similar p23 reliance, we tested the effect of HDAC1 in the presence and absence of p23. "
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