Study Identifies Gene Expression Program Supporting Sustained Neuronal Network Activity
Researchers developed a technique called CalTRAP-seq to profile gene expression in active neurons and discovered a distinct molecular program that supports sustained network bursting activity. Unlike the well-known immediate early gene responses triggered by acute stimuli, this program is enriched for regulators of neuronal excitability and involves widespread alternative splicing of synaptic genes. The findings shed light on how neurons coordinate long-lasting molecular changes to maintain stable network function, with potential implications for understanding neurological conditions involving disrupted network activity.
Scientists developed CalTRAP-seq, a method that uses calcium-dependent ribosome tagging to capture gene expression specifically in neurons that are actively firing within a network. When applied to primary neurons undergoing synchronous network bursting, the technique revealed a gene expression program distinct from stimulus-induced immediate early gene responses, instead characterized by regulators of neuronal excitability. The program was also accompanied by widespread alternative splicing of synaptic genes, suggesting that post-transcriptional regulation plays a significant role in network-level adaptation. A notable structural finding was that neurons participating in network activity showed increased formation of nuclear speckles — condensates known to be involved in splicing regulation. When nuclear speckles were experimentally disrupted, synchronous burst dynamics were impaired, providing functional evidence for their role in sustaining network activity. Together, the results identify a complementary layer of gene regulation that operates alongside stimulus-responsive programs to support stable neuronal network function.
What's missing
The study does not address whether the CalTRAP-seq findings generalize beyond primary neuron cultures to intact brain circuits in vivo, nor whether the identified gene expression program is conserved across different neuron types or brain regions. It is also unclear whether the alternative splicing events observed are causally necessary for sustained bursting or are correlative byproducts of network activity.
What different sources said
- bioRxivCenter
A Neuronal Gene Expression Program Underlying Sustained Network Activity
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