Thank you Fred! We have been influenced by many of your works.

4. O-GlcNAcylation also interacts with phosphorylation. (They both modify serine, threonine and tyrosine.)

3. Rhythmic O-GlcNAcylation directly modulates proteins involved in gene expression.

2. This rhythm is responsive to changes in mealtime. (So glad that TMT proteomics worked out for this PTM!)

1. Nuclear protein O-GlcNAcylation shows daily rhythms in mouse liver.

These led us to explore whether proteome-wide O-GlcNAcylation mediates the effect of mealtime in rhythmic liver gene expression. We found:

We started out asking how mealtime regulates genome-wide rhythmic gene expression. We knew several nutrient-sensitive pathways are involved. We knew O-GlcNAcylation, a nutrient-sensitive protein modification, modulates CLOCK, BMAL1 and PER2.