Nuclear Calcium Buffering Capacity Shapes Neuronal Architecture

Area of Science:

• Neuroscience
• Molecular Biology
• Cell Biology

Background:

• Calcium-binding proteins (CaBPs) regulate intracellular calcium dynamics, crucial for neuronal function.
• CaBPs in the cytosol impact synaptic plasticity, but nuclear roles are less understood.
• Nuclear calcium signals regulate gene expression, influencing neuronal development and function.

Purpose of the Study:

• To investigate the role of nuclear calcium buffering capacity in regulating neuronal architecture.
• To determine how CaBPs in the nucleus affect the expression of nuclear calcium-regulated genes.
• To link nuclear calcium buffering to dendritic morphology and spine density.

Main Methods:

• Utilized mouse hippocampal neurons.
• Expressed a nuclearly targeted parvalbumin fusion protein (PV.NLS-mC) to increase nuclear calcium buffering.
• Quantified expression levels of VEGFD and C1q-c mRNA.
• Assessed dendritic length, complexity, and spine density.

Main Results:

• Increased nuclear calcium buffering reduced VEGFD expression, leading to decreased dendritic length and complexity.
• Increased nuclear calcium buffering elevated C1q-c mRNA levels, reducing dendritic spine density and size.
• Demonstrated a direct link between nuclear calcium buffering and the transcription of genes controlling neuronal structure.

Conclusions:

• Nuclear calcium buffering capacity is a key regulator of neuronal architecture.
• Modulation of nuclear CaBPs affects genes controlling dendrite geometry and spine density.
• Deregulation of CaBPs in neurological conditions may impair neuronal structure by altering nuclear calcium buffering.