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07:17
Purification of Hsp104, a Protein Disaggregase
Published on: September 30, 2011
Evolutionary and physiological importance of hub proteins
Nizar N Batada1, Laurence D Hurst, Mike Tyers
1Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Canada. nizar.batada@gmail.com
Plos Computational Biology
|July 15, 2006
Summary
Hub proteins are physiologically important and tightly regulated, but contrary to claims, they do not evolve slowly. This study used curated protein interaction data to analyze protein hubs in Saccharomyces cerevisiae.
Area of Science:
- Molecular Biology
- Systems Biology
- Evolutionary Biology
Background:
- Protein interaction hubs are hypothesized to be physiologically important and slow-evolving due to high binding site density.
- Previous analyses yielded conflicting results, potentially due to unreliable protein interaction data.
Purpose of the Study:
- To investigate the relationship between protein connectivity (hub status), physiological importance, and evolutionary rate.
- To utilize a high-quality, literature-curated protein interaction dataset for Saccharomyces cerevisiae.
Main Methods:
- Analysis of a comprehensive, literature-curated dataset of well-substantiated protein interactions in Saccharomyces cerevisiae.
- Comparison of results obtained from less reliable yeast two-hybrid data versus higher quality datasets.
- Assessment of local connectivity, dispensability, evolutionary rate, binding site density, mRNA decay rates, and phosphorylation sites in hub proteins.
Main Results:
- A robust correlation between local connectivity and dispensability was observed using higher quality datasets, unlike with less reliable data.
- Local connectivity did not correlate with the rate of protein evolution, even in reliable datasets.
- Hub proteins showed rapid turnover and regulation (high mRNA decay, many phosphorylation sites), but not a higher density of binding residues.
Conclusions:
- Hub proteins are critical for cellular growth and are tightly regulated.
- Hub proteins are not slow evolving; their rapid turnover may prevent unwanted pathway activation.
- High-quality protein interaction data is crucial for accurate biological insights.
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