Description:

Plasma membrane heterogeneity has been tied to a litany of cellular functions and is often explained by analogy to membrane phase separation, yet models based on phase separation alone fall short of describing the rich organization available within cell membranes. This talk will present an updated model of plasma membrane heterogeneity in which functional membrane domains assemble in response to protein scaffolds drawing from recent measurements in intact cells and model membranes. Quantitative super-resolution nanoscopy measurements in live B lymphocytes detect membrane domains that emerge upon clustering B cell receptors (BCR). These domains have a tunable compositional contrast that integrates the stimulus with the membrane thermodynamic state to tune the functional response.  Proteins and nucleic acids can also undergo liquid-liquid phase separation and this talk will describe evidence that these biomolecules can assemble into surface phases at membranes whose stability can be enhanced by the membrane phase transition. 

Host: Petia Vlahovska, Professor of Engineering Sciences and Applied Mathematics, Northwestern University