Neuronal activity drives PCDH9 cleavage and nuclear translocation to coordinate structural and functional remodeling

Area of Science:

• Neuroscience
• Molecular Biology
• Genetics

Background:

• Protocadherins (PCDHs) are crucial for neurodevelopment and synaptic function.
• PCDH9 is associated with Autism Spectrum Disorder and Major Depressive Disorder.

Purpose of the Study:

• To investigate a novel activity-dependent signaling pathway for PCDH9.
• To understand how PCDH9 influences neuronal structure and function.

Main Methods:

• Biochemical assays
• Immunohistochemistry
• Neuronal cultures

Main Results:

• Neuronal activity induces Matrix Metalloprotease (MMP)-dependent cleavage of PCDH9.
• The resulting C-terminal fragment (CTF) translocates to the nucleus.
• PCDH9 CTF overexpression increases dendritic growth, spine density, and excitatory synaptic transmission.

Conclusions:

• PCDH9 CTF is a novel signaling molecule linking synaptic activity to neuronal remodeling.
• This pathway provides a new mechanism for how synaptic activity shapes neuronal properties.