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Updated: Jul 10, 2026
11:27
Selective Tracing of Auditory Fibers in the Avian Embryonic Vestibulocochlear Nerve
Published on: March 18, 2013
Netrin-G2 and netrin-G2 ligand are both required for normal auditory responsiveness
W Zhang1, I Rajan, K V Savelieva
1Neuroscience Research, Lexicon Pharmaceuticals Inc., The Woodlands, TX, USA.
Genes, Brain, and Behavior
|November 2, 2007
Summary
Genetic inhibition of netrin-G2 in mice prevents acoustic startle response without affecting auditory brainstem responses. This suggests netrin-G2 is crucial for auditory synaptic function.
Area of Science:
- Neuroscience
- Auditory System Research
- Molecular Biology
Background:
- Netrin-G2 is a protein implicated in neural development.
- The precise role of netrin-G2 in auditory processing remains unclear.
Purpose of the Study:
- To investigate the function of netrin-G2 in auditory startle response.
- To explore the interaction between netrin-G2 and its ligand in vivo.
Main Methods:
- Genetic inhibition of netrin-G2 in mice.
- Behavioral testing battery, including acoustic startle response.
- Auditory brainstem response (ABR) measurements.
- Biochemical assays to determine protein affinity.
Main Results:
- Mice with inhibited netrin-G2 showed no acoustic startle response.
- Auditory brainstem responses were present, indicating intact inner ear and auditory nerve function.
- Genetic inhibition of the netrin-G2 ligand yielded a similar phenotype.
- A strong binding affinity (2.5 nM) was observed between netrin-G2 and its ligand.
Conclusions:
- Netrin-G2 and its ligand interact in a receptor-ligand relationship.
- This interaction is essential for auditory synaptic responsiveness in the brain.
- Netrin-G2 plays a critical role specifically in the auditory startle pathway.
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