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Related Experiment Video

Updated: May 10, 2026

Monitoring Cell-autonomous Circadian Clock Rhythms of Gene Expression Using Luciferase Bioluminescence Reporters

Monitoring Cell-autonomous Circadian Clock Rhythms of Gene Expression Using Luciferase Bioluminescence Reporters

Published on: September 27, 2012

A circadian sleep disorder reveals a complex clock.

Emmanuel Mignot¹, Joseph S Takahashi

¹Howard Hughes Medical Institute, Stanford University School of Medicine, 701-B Welch Road, Stanford, CA 94304, USA. mignot@stanford.edu

|January 16, 2007

Summary

Familial advanced sleep phase syndrome is linked to a human PER2 mutation. This study reveals complex PER2 phosphorylation affecting protein levels and circadian period length.

Area of Science:

Chronobiology
Molecular genetics
Sleep medicine

Background:

Circadian rhythms govern daily physiological cycles through clock gene transcription and feedback loops.
Familial advanced sleep phase syndrome (FASPS) is a disorder linked to mutations in circadian clock genes.
The PER2 protein is a key component of the molecular circadian clockwork.

Discussion:

This study investigates a human PER2 mutation associated with FASPS using a mouse model.
The research examines the impact of mutations on PER2 protein phosphorylation by kinases like CK1delta.
Understanding PER2 phosphorylation is crucial for deciphering circadian rhythm regulation.

Key Insights:

PER2 phosphorylation is more complex than previously thought.

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Last Updated: May 10, 2026

Monitoring Cell-autonomous Circadian Clock Rhythms of Gene Expression Using Luciferase Bioluminescence Reporters

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Published on: September 27, 2012

Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures

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Published on: November 11, 2016

Collecting Sleep, Circadian, Fatigue, and Performance Data in Complex Operational Environments

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Published on: August 8, 2019

Specific PER2 phosphorylation events have opposing effects on PER2 protein levels.

These phosphorylation events also influence the length of the circadian period.

Outlook:

Further research into PER2 phosphorylation could reveal novel therapeutic targets for circadian rhythm disorders.
This work deepens our understanding of the molecular mechanisms underlying sleep phase syndromes.
Characterizing kinase interactions with PER2 may elucidate broader principles of clock gene regulation.