REV, A BRET-Based Sensor of ERK Activity.

Area of Science:

• Cellular signaling and molecular biology
• Neuroscience and cell dynamics

Background:

• Cellular signaling networks process environmental cues through dynamic spatial and temporal integration.
• Bioluminescence resonance energy transfer (BRET)-based biosensors offer high sensitivity for monitoring molecular events in living cells.
• Extracellular signal-regulated kinases (ERK) are crucial for diverse cellular functions, with activation patterns potentially encoding specific information.

Purpose of the Study:

• To engineer and validate a novel BRET-based biosensor for monitoring Extracellular signal-regulated kinases (ERK) activity.
• To investigate the spatio-temporal dynamics of ERK activation in neurons.
• To determine how ERK activation patterns encode information about external stimuli.

Main Methods:

• Development of a BRET-based biosensor, Rluc8-ERKsubstrate-Venus (REV), for ERK activity.
• Validation of REV by correlating BRET changes with ERK phosphorylation.
• Application of the REV sensor in neurons to observe ERK activation in response to stimuli.

Main Results:

• The REV biosensor demonstrated BRET changes that correlated with ERK phosphorylation, confirming its ability to report kinase activity.
• In neurons, the strength, location, and timing of ERK activation were modulated by the nature of the stimulus.
• These findings indicate that the spatio-temporal modulation of ERK activation encodes specific information about the initial stimulus.

Conclusions:

• The REV biosensor is a suitable tool for studying biological questions related to ERK signaling.
• Dynamic modulation of ERK activation in neurons plays a critical role in specifying cellular responses to stimuli.
• This work provides a new method for dissecting complex signaling events in real-time.