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Updated: May 17, 2026
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Genetic and Biochemical Approaches for In Vivo and In Vitro Assessment of Protein Oligomerization: The Ryanodine Receptor Case Study
Published on: July 27, 2016
The native GCN4 leucine-zipper domain does not uniquely specify a dimeric oligomerization state
Kaylyn M Oshaben1, Reza Salari, Darrell R McCaslin
1Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA.
Biochemistry
|November 3, 2012
Summary
The GCN4 transcription factor
Area of Science:
- Protein structure and folding
- Biophysics
- Molecular biology
Background:
- The GCN4 leucine zipper is a model for alpha-helical coiled-coil folding.
- It has been widely studied, with mutations known to alter oligomerization states.
- The wild-type sequence was assumed to form only dimers.
Purpose of the Study:
- To investigate the oligomerization state of the wild-type GCN4 coiled-coil domain.
- To determine if environmental factors influence its fold.
- To provide a more complex understanding of GCN4 folding behavior.
Main Methods:
- High-resolution crystal structure determination of dimeric and trimeric assemblies.
- Biophysical measurements in solution.
- Microsecond-scale parallel tempering molecular dynamics simulations.
Main Results:
- The wild-type GCN4 coiled-coil domain can form both dimeric and trimeric structures.
- Both oligomerization states are present under specific experimental conditions.
- Simulations revealed comparable stability between the dimer and trimer folded states.
Conclusions:
- GCN4 coiled-coil domain folding is more complex than previously thought.
- Findings impact predictive algorithms for coiled-coil folds.
- Results guide the selection of model systems for coiled-coil research.
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