Artificial signaling in mammalian cells enabled by prokaryotic two-component system

Area of Science:

• Synthetic biology
• Genetic engineering
• Mammalian cell signaling

Background:

• Two-component signaling pathways are crucial in bacteria but challenging to implement in mammalian cells.
• Previous attempts in mammalian cells lost essential ligand sensitivity.
• Engineering new signal transduction capabilities in cells is a key goal.

Purpose of the Study:

• To restore ligand sensitivity and dose-dependent control to two-component signaling in mammalian cells.
• To develop a method for transducing small-molecule signals into gene expression.
• To create orthogonal signaling pathways in mammalian systems.

Main Methods:

• Engineered truncated histidine kinase mutants that require dimerization for function.
• Fused these mutants to domains that dimerize upon ligand binding.
• Implemented cytoplasmic and cell-surface signaling strategies for different ligand types.

Main Results:

• Achieved ligand-dependent dimerization of engineered signaling components.
• Demonstrated dose-dependent gene expression in response to small-molecule ligands.
• Successfully transduced both cytoplasmic and extracellular signals into cellular responses.

Conclusions:

• Developed a versatile two-component system for controllable gene expression in mammalian cells.
• Showcased the potential of these systems for creating novel orthogonal signaling pathways.
• Enabled precise control of cellular functions using small-molecule inputs.