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Updated: Oct 31, 2025
09:42
Simultaneous Electrophysiological Recording and Calcium Imaging of Suprachiasmatic Nucleus Neurons
Published on: December 8, 2013
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Light-induced changes in the suprachiasmatic nucleus transcriptome regulated by the ERK/MAPK pathway
Diego Alzate-Correa1, Sydney Aten2, Moray J Campbell1
1Division of Pharmaceutics and Pharmacology, Ohio State University, Columbus, OH, United States of America.
Plos One
|June 30, 2021
Summary
The ERK/MAPK pathway regulates circadian clock timing by controlling light-evoked gene expression. This signaling pathway is crucial for the suprachiasmatic nucleus
Area of Science:
- Chronobiology
- Molecular Biology
- Neuroscience
Background:
- The mammalian circadian clock, located in the suprachiasmatic nucleus (SCN), synchronizes to the 24-hour light/dark cycle.
- Light entrainment involves a clock-gated response in oscillator sensitivity to light.
- The ERK/MAPK pathway is implicated in rapid, light-induced gene expression.
Purpose of the Study:
- To investigate the role of ERK/MAPK signaling in light-evoked gene expression within the SCN.
- To understand how light exposure at different circadian times influences gene regulation.
- To elucidate the transcriptional mechanisms underlying circadian clock entrainment.
Main Methods:
- RNA array-based profiling was employed to analyze gene expression changes.
- Pharmacological methods were used to disrupt ERK/MAPK signaling.
- Transient photic stimulation was applied at different circadian times (day vs. night).
Main Results:
- Photic stimulation during the circadian night, but not day, induced significant gene expression changes.
- Early-night light primarily increased gene expression, while late-night light predominantly caused downregulation.
- Disruption of MAPK signaling substantially reduced light-evoked gene regulation, particularly during the late night.
Conclusions:
- ERK/MAPK signaling is essential for gating circadian gene expression in response to light.
- This pathway plays a critical role in the transcriptional regulation of circadian clock entrainment.
- The findings provide insights into the molecular mechanisms linking light, gene expression, and circadian timing.
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