An improved FLARE system for recording and manipulating neuronal activity.

Area of Science:

• Neuroscience
• Molecular Biology
• Genetics

Background:

• Existing methods for neuronal ensemble manipulation lack precision.
• A need exists for tools to tag and control specific neuronal populations linked to behaviors.

Purpose of the Study:

• To introduce cytoFLARE, an improved version of FLARE for enhanced neuronal activity recording and manipulation.
• To characterize cytoFLARE's performance in cellular and in vivo models.

Main Methods:

• Developed cytoFLARE by incorporating cytosolic tethering and sensitive calcium-sensing domains.
• Tested cytoFLARE in HEK293T cells and neuronal cultures for signal detection.
• Established cytoFLARE transgenic Drosophila models for in vivo studies.
• Utilized cytoFLARE to drive optogenetic actuators for neuronal manipulation.

Main Results:

• cytoFLARE demonstrated improved calcium- and light-dependent signal capture and higher signal-to-background ratios.
• Successfully labeled activated neurons in Drosophila larvae following stimulation.
• Achieved reactivation and inhibition of neurons in the larval nociceptive system using cytoFLARE.

Conclusions:

• cytoFLARE represents a significant advancement in time-gated calcium integrators.
• The tool enables both recording and manipulation of neuronal activity with temporal precision.
• cytoFLARE provides a powerful system for studying neural circuits in Drosophila larvae.