Summary
This study identifies Brn3b and downstream neuropeptide Tac2 as critical molecular regulators of midbrain circuits that mediate defensive responses to visual threats. While primarily basic neuroscience, the findings contribute to understanding how visual signals are processed beyond the retina in fear-related contexts, with potential implications for understanding visual stress responses in built environments.
Key Findings
- Midbrain-specific deletion of transcription factor Brn3b caused loss of neurons projecting to the lateral posterior nucleus of the thalamus
- Brn3b deletion downregulated expression of neuropeptide tachykinin 2 (Tac2)
- Brn3b mutant mice displayed impaired defensive freezing responses to visual threat under social isolation conditions
- Overexpression of Tac2 ameliorated the impaired defensive freezing phenotype, confirming Tac2 acts downstream of Brn3b in this circuit
Categories
The Science of Light: Investigates midbrain visual circuits and transcription factors involved in processing visual threat stimuli, relevant to understanding non-image-forming visual pathways.
Author(s)
H Lee, H Weinberg-Wolf, HL Lee, T Lee, J Conte
Publication Year
2023
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