Regulation of persistent sodium currents by glycogen synthase kinase 3 encodes daily rhythms of neuronal excitability.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 27841351.
- Also identified by DOI 10.1038/ncomms13470 and PMC identifier 5114562.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
How neurons encode intracellular biochemical signalling cascades into electrical signals is not fully understood. Neurons in the central circadian clock in mammals provide a model system to investigate electrical encoding of biochemical timing signals. Here, using experimental and modelling approaches, we show how the activation of glycogen synthase kinase 3 (GSK3) contributes to neuronal excitability through regulation of the persistent sodium current (I<sub>NaP</sub>). I<sub>NaP</sub> exhibits a day/night difference in peak magnitude and is regulated by GSK3. Using mathematical modelling, we predict and confirm that GSK3 activation of I<sub>NaP</sub> affects the action potential afterhyperpolarization, which increases the spontaneous firing rate without affecting the resting membrane potential. Together, these results demonstrate a crucial link between the molecular circadian clock and electrical activity, providing examples of kinase regulation of electrical activity and the propagation of intracellular signals in neuronal networks.
Medical subject headings
- Glycogen Synthase Kinase 3
- Neurons
- Sodium
- Sodium Channels