A billion years of evolution manifest in nanosecond protein dynamics

TL;DR

This study investigates how billion-year evolutionary divergence influences nanosecond protein dynamics across homologs, revealing conserved kinetic footprints and subtle temporal shifts linked to evolutionary history, with implications for molecular paleontology.

Contribution

It provides the first detailed comparison of ultrafast protein dynamics across species separated by nearly a billion years, highlighting conserved processes and evolutionary effects.

Findings

Identified three conserved dynamic activity points in protein complexes.

Discovered a subtle temporal shift correlating with evolutionary divergence.

Proposed a new approach linking protein dynamics to molecular paleontology.

Abstract

Protein dynamics form a critical bridge between protein structure and function, yet the impact of evolution on ultrafast processes inside proteins remains enigmatic. This study delves deep into nanosecond-scale protein dynamics of a structurally and functionally conserved protein across species separated by almost a billion years, investigating ten homologs in complex with their ligand. By inducing a photo-triggered destabilization of the ligand inside the binding pocket, we resolved distinct kinetic footprints for each homolog via transient infrared spectroscopy . Strikingly, we found a cascade of rearrangements within the protein complex which manifest in three discrete time points of dynamic activity, conserved over hundreds of millions of years within a narrow window. Among these processes, one displays a subtle temporal shift correlating with evolutionary divergence, suggesting reduced selective pressure in the past. Our study not only uncovers the impact of evolution on molecular processes in a specific case, but has also the potential to initiate a novel field of scientific inquiry within molecular paleontology, where species are compared and classified based on the rapid pace of protein dynamic processes; a field which connects the shortest conceivable time scale in living matter (10^-9 s) with the largest ones (10^16 s).