Performance of the molecular oscillator
The researchers' team has discovered that miR-122 is tightly embedded in the output system of the circadian clock in hepatocytes. This microRNA regulates numerous circadian genes, impinging on the amplitude and duration of their expression. Conversely, the synthesis of miR-122 involves a transcription factor that is otherwise known for its function in the circadian clock.
and viral replication
"It will be exciting to investigate whether the connection between circadian rhythms and miR-122 also extends to this microRNA's role in hepatitis C virus replication", points out David Gatfield. Knowing whether viral multiplication is gated to specific times of the day would contribute significantly to our understanding of the life cycle of this formidable pathogen.
Scientists have uncovered over the past years the role of microRNAs in crucial physiological functions such as growth and programmed cell death, as well as carcinogenesis. Ueli Schibler's team adds a stone to this edifice by placing miR-122 within the clock gene machinery.
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