Fluctuating Diffusivity of RNA-Protein Particles: Analogy with Thermodynamics

A formal analogy of fluctuating diffusivity to thermodynamics is discussed for messenger RNA molecules fluorescently fused to a protein in living cells. Regarding the average value of the fluctuating diffusivity of such RNA-protein particles as the analog of the internal energy, the analogs of the quantity of heat and work are identified. The Clausius-like inequality is shown to hold for the entropy associated with diffusivity fluctuations, which plays a role analogous to the thermodynamic entropy, and the analog of the quantity of heat. The change of the statistical fluctuation distribution is also examined from a geometric perspective. The present discussions may contribute to a deeper understanding of the fluctuating diffusivity in view of the laws of thermodynamics.

Automated summary

By analogizing fluctuating diffusivity to thermodynamics, this study delves into the fluctuating diffusivity of messenger RNA molecules fluorescently fused to a protein in living cells. The research identifies the analogs of internal energy, heat, and work for RNA-protein particles, and shows that a Clausius-like inequality holds for the entropy associated with diffusivity fluctuations. Additionally, the change of the statistical fluctuation distribution is examined from a geometric perspective, contributing to a deeper understanding of fluctuating diffusivity in light of thermodynamic laws.