Clathrin-mediated endocytosis is driven by contact adhesion of a phase-separated protein body

Date

Jan 20, 2017

Time

11:00 AM - 12:00 PM

Speaker

Louis Bergeron-Sandoval

Affiliation

University of Montreal, Canada

Language

en

Main Topic

Biologie

Other Topics

Biologie

Host

Simon Alberti

Description

Progression of clathrin-mediated endocytosis (CME) in yeast, in absence of turgor and F-actin polymerization, constitutes an elusive mechanism. We postulated that the condensation of PrD-containing proteins on cortical sites forms, through protein phase separation, a viscoelastic body capable of bending the plasma membrane in this context. With imaging and micro rheological techniques, we confirmed that a group of disordered proteins, that coalesce on cortical sites, are assembled through phase separation into nanometer sized viscoelastic bodies. When these cortical bodies are nucleated between the membrane and cytoplasm, new adhesive interfaces are created and we propose - through a biophysical model - that free energy available at these interfaces can produce work to deform the surrounding materials. Experimental results further corroborated our model predictions and we thus present a novel mechanism that account for deformation of the membrane under action of the cortical bodies alone, when CME progression is decoupled from F-actin polymerization.

Last modified: Jan 21, 2017, 8:52:13 AM