Skip to Content

Search: {{$root.lsaSearchQuery.q}}, Page {{$root.page}}

Biophysics Seminar: Prof. Sarah Veatch, Assistant Professor of Physics and Assistant Professor Physics at the University of Michigan

"Phases and Fluctuations in Biological Membranes"
Friday, September 30, 2016
4:00-5:00 PM
1300 Chemistry Dow Lab Map
Abstract:
The thermodynamic properties of plasma membrane lipids play a vital role in many functions at the mammalian cell surface. Some functions are thought to occur, at least in part, because plasma membrane lipids have a tendency to separate into two distinct liquid phases. We propose that these lipid mediated functions occur because the plasma membrane is biologically tuned close to a miscibility critical point at physiological temperature. In this talk, I will summarize experimental support for this hypothesis as well as our recent efforts to tie membrane mixing properties to biological functions. Since joining the faculty at the University of Michigan, my group has developed and optimized quantitative super-resolution fluorescence localization methods that achieve the sensitivity needed to directly observe phase-like domains in chemically fixed and live cells. In B cells, we find that stabilizing domains resembling one phase acts to sort membrane bound kinases and phosphatases, establishing local regions of enhanced tyrosine phosphorylation. We have developed a minimal model whereby this effect drives the activation of B cell receptors upon clustering with multivalent soluble antigen, facilitating the cellular immune response. We also have identified a range of experimental conditions that allow us to manipulate mixing, and we are using these to explore the impacts of heterogeneity on function in both cells and animals. Some of these biochemical perturbations are well characterized general anesthetics, and I will present evidence supporting a mechanistic role for membrane heterogeneity in general anesthesia. Together, these studies support a paradigm where lipids contribute to the regulation of biochemical pathways occurring at the cell surface, by tuning their interactions, increasing cooperativity, and influencing internal states of embedded proteins.
Building: Chemistry Dow Lab
Event Type: Workshop / Seminar
Tags: Chemistry
Source: Happening @ Michigan from LSA Biophysics