A single-vector intersectional AAV strategy for interrogating cellular diversity and brain function.

Area of Science:

• Neuroscience
• Molecular Biology
• Genetics

Background:

• The increasing discovery of cellular diversity in the brain necessitates advanced tools for precise cell targeting.
• Existing intersectional expression platforms have limitations in targeting flexibility and payload capacity.

Purpose of the Study:

• To develop and validate a novel viral vector system, ConVERGD, for intersectional targeting of neuronal subtypes.
• To characterize a previously unexplored subpopulation of norepinephrine-producing neurons in the rodent locus coeruleus.

Main Methods:

• Development of Conditional Viral Expression by Ribozyme Guided Degradation (ConVERGD), an adeno-associated virus-based system.
• ConVERGD combines ribozymes and FLEx switches for single-construct, intersectional targeting.
• Application of ConVERGD to identify norepinephrine (NE)-producing neurons co-expressing prodynorphin (Pdyn) in the locus coeruleus.

Main Results:

• ConVERGD enables expanded intersectional targeting (up to five recombinase features) and accommodates larger payloads.
• A novel subpopulation of Pdyn-expressing NE+ locus coeruleus neurons was identified.
• These neurons were found to drive anxiogenic behavioral responses in rodents.

Conclusions:

• ConVERGD is a versatile tool for targeting diverse neuronal subtypes with enhanced flexibility and capacity.
• The Pdyn-expressing NE+ locus coeruleus neurons represent a distinct, functionally relevant neuronal population.
• This study highlights ConVERGD's utility in uncovering novel cell populations and their functions.