What is the Origin of Molecular Oscillator Feedback?

This term is central to the field of molecular chronobiology, stemming from the discovery of the core clock genes in various organisms. 'Molecular Oscillator' describes the self-sustaining, periodic nature of the genetic mechanism, while 'Feedback' refers to the transcriptional-translational loops that drive the 24-hour cycle. The mechanism was first fully characterized in the fruit fly and later confirmed in mammals.

What is the Mechanism of Molecular Oscillator Feedback?

The primary loop involves the heterodimer of CLOCK and BMAL1 proteins activating the transcription of the Period (PER) and Cryptochrome (CRY) genes. The PER and CRY proteins then accumulate in the cytoplasm, translocate back into the nucleus, and repress the activity of the CLOCK/BMAL1 complex, thereby inhibiting their own transcription. This repression leads to the degradation of PER and CRY, allowing CLOCK/BMAL1 activity to resume, completing the 24-hour negative feedback cycle.

Molecular Oscillator Feedback ∞ Area

Molecular Oscillator Feedback

Meaning

Molecular Oscillator Feedback refers to the core genetic and protein-based autoregulatory loops that generate the intrinsic, approximately 24-hour rhythmicity within individual cells, constituting the molecular clock. This feedback system involves a set of clock genes and their protein products cyclically activating and repressing their own transcription. The precise functioning of this feedback loop is the foundation of all circadian rhythms in the body.