Quantifying the Monomer-Dimer Equilibrium of Tubulin with Mass Photometry

The alpha beta-tubulin heterodimer is the fundamental building block of microtubules, making it central to several cellular processes. Despite the apparent simplicity of heterodimerisation, the associated energetics and kinetics remain disputed, largely due to experimental challenges associated with quantifying affinities in the 10(-2) s(-1). Our results demonstrate the capabilities of mass photometry for quantifying protein-protein interactions and clarify the energetics and kinetics of tubulin heterodimerisation. (C) 2020 The Author(s). Published by Elsevier Ltd.