Protein-making control plays a key role in daily gene activity rhythms

Ribosome profiling in a human cell model revealed that most rhythmic gene expression occurs with minimal delay between transcription and translation.

• The lag in the accumulation of some clock proteins relative to their mRNAs does not appear to result from regulated translation.
• Translation occurs in a circadian manner for many genes, adding an extra layer of control over rhythmically expressed mRNAs.
• Rhythmic translation is observed for most cyclically transcribed RNAs at two major times during a 24-hour day.
• Most noncyclic RNAs exhibit rhythmic translation phased to a single time of day.
• The circadian clock also regulates the formation of cytoplasmic processing bodies, which influence mRNA metabolism.

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