An engineered protein-phosphorylation toggle network with implications for endogenous network discovery

Area of Science:

• Synthetic biology
• Molecular and cellular biology
• Biochemistry

Background:

• Fast, reversible reactions are key for engineering novel cellular behaviors.
• Existing regulatory systems often rely on slower mechanisms.
• Synthetic biological networks offer potential for rapid cellular control.

Purpose of the Study:

• To engineer a synthetic bistable toggle switch in Saccharomyces cerevisiae using protein-protein phosphorylation.
• To develop a computational framework for identifying endogenous bistable networks.
• To experimentally validate newly discovered endogenous bistable networks.

Main Methods:

• Construction of a synthetic toggle switch utilizing a cross-repression topology with 11 protein-protein phosphorylation elements.
• Development of a computational framework to search endogenous protein pathways for bistable networks.
• Experimental verification of identified endogenous networks for bistability.

Main Results:

• Successfully created an ultrasensitive synthetic toggle switch in yeast that switches states within seconds and maintains long-term bistability.
• Identified and experimentally verified five previously unreported endogenous biological networks exhibiting bistability.
• Demonstrated the utility of the computational framework for discovering functional biological networks.

Conclusions:

• Synthetic protein-protein networks can be rapidly engineered for sophisticated cellular regulation.
• The developed computational framework aids in the discovery of endogenous networks with specific functions.
• This research paves the way for designing fast sensing and processing systems in bioengineering.