FLIM-FRET as a Molecular Filter for Membrane-Induced Aggregation

Authors

Salem, A., Qi, W., Rochet, J.-C., Webb, K. J.

Abstract

Membrane binding is thought to trigger early aggregation of alpha-synuclein (aSyn) in neurons. However, live-cell measurements of membrane-proximal aggregation with high specificity remain challenging. We combine three-channel fluorescence lifetime imaging microscopy (FLIM) with Forster resonance energy transfer (FRET) in a model that uses FRET as a proximity filter. A membrane-tethered donor reports membrane-aSyn separation through lifetime changes, while an aSyn-labeled acceptor reports the aggregation state through its lifetime. We estimate per-cell lifetimes and mixture fractions for membrane-bound and membrane-unbound populations using a hierarchical expectation-maximization (EM) algorithm that pools information across pixels. We validate the estimator using Monte Carlo studies. Using experimental neuronal data, this method resolves changes in membrane-proximal aggregation and aggregate-associated lifetimes. This framework provides quantitative per-cell metrics linking membrane proximity and aggregation for comparative live-cell studies.

Preprint server: bioRxiv
The authors list and abstract were imported from bioRxiv on 16 Mar 2026.

Stats

1-terrible, 9-excellent. How would you rate this preprint? Sign in in to submit your rating.

Post a comment

You need to be signed in to post comments. You can sign in here.

Comments

There are no comments yet.