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bioRxiv · 10.1101/2025.07.10.664133

Self-consistent analytical solutions to the kinetics of lipid-induced protein aggregation

Stevenson, A.·Voderholzer, D.·Michaels, T. C. T.
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Abstract

The aggregation of proteins into amyloid fibrils is a hallmark of several neurodegenerative disorders, including Parkinsons disease. A growing body of experimental evidence highlights the significant role lipid membranes play in modulating this aggregation process, particularly for proteins such as -synuclein. Despite this, there has been a lack of quantitative theoretical frameworks capable of describing the kinetics of lipid-induced protein aggregation. In this work, we develop an analytical model that explicitly incorporates lipid-mediated interactions into the aggregation kinetics. By formulating rate equations in terms of lipid surface coverage and applying a fixed-point analysis, we derive self-consistent solutions for the full timecourse of aggregation. Our model captures both one-step and two-step nucleation mechanisms and enables the prediction of key kinetic observables, including half-times and maximal growth rates. These results provide a quantitative foundation for interpreting experimental data and offer new mechanistic insights into how lipids influence the self-assembly of amyloidogenic proteins.

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Stevenson, A., Voderholzer, D., Michaels, T. C. T.. 2025-07-15. Self-consistent analytical solutions to the kinetics of lipid-induced protein aggregation. https://doi.org/10.1101/2025.07.10.664133

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