Ubiquitination of glycogen and metabolites in cells and tissues
Nature • • health
Key Points:
- Researchers have developed Non-Protein Ub-clipping (NoPro-clipping), a mass-spectrometry technique that detects ubiquitination on non-protein substrates like sugars, lipids, and nucleotides, which were previously undetectable by standard methods.
- Using NoPro-clipping, the study identified ubiquitinated glycogen in various mouse tissues, especially liver and skeletal muscle, revealing that ubiquitination regulates glycogen delivery to lysosomes and reduces glycogen levels.
- Glycogen ubiquitination is influenced by glycogen storage diseases and the Met1-polyubiquitin machinery, and it increases during fasting, indicating a role for ubiquitin in normal glycogen breakdown.
- The research also discovered ubiquitination of endogenous glycerol and spermine, expanding the understanding of ubiquitin as a modifier beyond proteins to a wide range of biomolecules.
- This work broadens the biological significance of ubiquitin signalling, highlighting its involvement in regulating diverse cellular substrates and metabolic processes.
