Fear conditioning biases olfactory sensory neuron frequencies across generations

Area of Science:

• Neuroscience
• Genetics
• Olfactory System Biology

Background:

• The main olfactory epithelium is crucial for odor encoding.
• Recent research indicates fear conditioning can cause inherited changes in the olfactory system.
• These changes include altered olfactory sensory neuron activity and odor responses.

Purpose of the Study:

• To investigate cellular composition changes in the olfactory epithelium following an aversive stimulus.
• To determine if olfactory fear conditioning impacts neurogenesis in parent mice and their offspring.

Main Methods:

• Utilized volumetric cellular analysis to examine the olfactory epithelium.
• Conducted odor-shock conditioning in parent mice (F0) and analyzed their unconditioned offspring (F1).
• Assessed behavioral responses to odors in F1 offspring.

Main Results:

• Olfactory fear conditioning increased the number of odor-encoding neurons in both F0 mice and their F1 offspring.
• The increase in F0 mice was partly due to stem cell layer bias in the main olfactory epithelium.
• F1 offspring exhibited subtle odor-specific behavioral differences compared to offspring of unconditioned parents.

Conclusions:

• Olfactory fear conditioning leads to intergenerational regulation of olfactory epithelium composition.
• This study provides insights into the heritability of acquired phenotypes related to olfaction.
• Fear conditioning can induce lasting, transgenerational changes in the olfactory system and associated behaviors.