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Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures
Published on: November 11, 2016
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Nutrient-sensitive protein O-GlcNAcylation shapes daily biological rhythms
Xianhui Liu1,2, Joanna C Chiu1
1Department of Entomology and Nematology, College of Agricultural and Environmental Sciences, University of California Davis, Davis, CA, USA.
Open Biology
|September 13, 2022
Summary
O-linked-N-acetylglucosaminylation (O-GlcNAcylation) is a daily rhythm in cells, influenced by food intake timing. Disrupting this rhythm impacts biological timing and health span.
Area of Science:
- Biochemistry
- Molecular Biology
- Chronobiology
Background:
- O-linked-N-acetylglucosaminylation (O-GlcNAcylation) is a dynamic, nutrient-sensitive post-translational modification.
- Like phosphorylation, O-GlcNAcylation occurs on serine and threonine residues and influences protein function.
- Cellular O-GlcNAcylation exhibits daily rhythms, impacting circadian clock proteins and biological processes.
Purpose of the Study:
- To review mechanisms linking circadian and metabolic signals to daily O-GlcNAcylation rhythms.
- To explore how mistimed feeding disrupts these rhythms and affects health.
- To discuss the interplay between O-GlcNAcylation, other modifications, and biological rhythms.
Main Methods:
- Review of published literature on O-GlcNAcylation, circadian rhythms, and metabolism.
- Analysis of regulatory pathways involving the hexosamine biosynthetic pathway and O-GlcNAc processing enzymes.
- Discussion of functional interactions with other post-translational modifications.
Main Results:
- Daily O-GlcNAcylation rhythms are regulated by integrated circadian and metabolic signals in Drosophila.
- Mistimed feeding dampens O-GlcNAcylation rhythm, negatively impacting biological rhythms and health span.
- Rhythmic O-GlcNAcylation modulates organ/tissue-specific pathways, influencing time-of-day biology.
Conclusions:
- Circadian and metabolic signals converge to regulate daily O-GlcNAcylation rhythms.
- Disruption of feeding schedules can impair O-GlcNAcylation rhythms, with potential health consequences.
- Rhythmic O-GlcNAcylation is a key regulator of time-of-day-specific cellular functions and biological rhythms.
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