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Experience-Dependent Remodeling of Juvenile Brain Olfactory Sensory Neuron Synaptic Connectivity in an Early-Life Critical Period
Published on: March 1, 2024
Sequential onset of presynaptic molecules during olfactory sensory neuron maturation
Florencia Marcucci1, Dong-Jing Zou, Stuart Firestein
1Department of Biological Sciences, Columbia University, New York, New York 10027, USA.
The Journal of Comparative Neurology
|July 15, 2009
Summary
Mouse olfactory neurons mature through distinct presynaptic development stages, sequentially expressing specific genes. This intrinsic developmental program guides synapse formation, independent of target contact.
Area of Science:
- Neuroscience
- Molecular Biology
- Developmental Biology
Background:
- Olfactory sensory neurons (OSNs) require specific presynaptic proteins for synapse formation.
- Understanding presynaptic protein regulation is key to elucidating OSN differentiation and maturation.
- Synaptogenesis in the olfactory bulb is a critical step in sensory neuron development.
Purpose of the Study:
- To investigate the temporal expression patterns of presynaptic genes during OSN maturation.
- To determine if OSN presynaptic development follows an intrinsic program or is influenced by target contact.
Main Methods:
- Design and utilization of specific in situ hybridization probes for presynaptic protein messenger RNAs.
- Analysis of gene expression patterns in developing mouse olfactory neurons.
Main Results:
- Mouse OSNs sequentially express specific presynaptic genes as they mature.
- Scaffolding protein genes are expressed early, while vesicle release regulatory genes are expressed later.
- Vesicle glutamate transporter 2, a marker for glutamatergic neurons, shows the latest onset of expression.
- Presynaptic gene expression is independent of olfactory bulb target contact, indicating an intrinsic developmental program.
Conclusions:
- OSN presynaptic development occurs in discrete, sequential steps.
- The maturation of OSN presynaptic machinery is regulated by an intrinsic program.
- Target contact is not the primary driver for presynaptic gene expression in OSNs.
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