Temperature compensation through kinetic regulation in biochemical oscillators

Area of Science:

• Biochemistry
• Systems Biology
• Chronobiology

Background:

• Circadian clocks are biological timekeepers essential for life.
• Temperature compensation (TC) is a key feature, maintaining clock period stability across temperatures.
• The underlying mechanisms for TC across diverse circadian systems remain largely unknown.

Purpose of the Study:

• To identify common features enabling temperature compensation in circadian clocks.
• To elucidate the general mechanism of robust temperature compensation in biological oscillators.

Main Methods:

• Analysis of generic oscillator models operating in the nonlinear regime.
• Investigation of period-lengthening reactions and their dependence on reaction rates.
• Comparison of theoretical models with experimental data, including the Kai system.

Main Results:

• Temperature compensation (TC) relies on period-lengthening reactions where increased rates lengthen the oscillation period.
• This counterintuitive dependence is characteristic of nonlinear oscillators operating far from onset, with distinct fast and slow phases.
• Robust TC arises from a balance between positive dependence on period-lengthening rates and inverse dependence on other kinetic rates.
• Higher energy dissipation correlates with improved TC performance.

Conclusions:

• A universal mechanism for temperature compensation in biochemical oscillators involves operating in nonlinear regimes with period-lengthening reactions.
• This mechanism ensures stable circadian rhythms despite environmental temperature variations.
• The findings provide a framework for understanding robust biological timing and its energetic costs.