The Department of Biomedicine

BBB seminar: Ilpo Vattulainen

Tiny but tough, cholesterol! How membranes sense changes in cholesterol structure

Ilpo Vattulainen
Department of Physics, Tampere University of Technology and Department of Physics, University of Helsinki, Finland

Cholesterol is one of the vital components in regulating the physical properties of animal cell membranes. Its effects on lipid membranes are quite exceptional given that other sterols are not as effective as cholesterol in modulating membrane properties such as order and elasticity, yet it remains unclear what renders cholesterol so unique. The complexity of cholesterol is further stressed by the fact that there are membrane proteins whose function is dependent on cholesterol, and it seems evident that other sterols are not able to replace cholesterol in maintaining protein function. In this talk, we discuss how membranes sense changes in cholesterol structure. We consider synthetic sterols non-existent in nature to elucidate the roles of cholesterol’s individual structural elements. We also discuss how oxysterols based on oxidation of cholesterol affect membrane properties in a manner that is distinct from cholesterol. The data emerged from atomistic molecular dynamics simulations as well as experiments, provide a basis to better understand why cholesterol is indeed unique in modulating membrane properties and membrane protein function, and can possibly be used to predict new synthetic sterols with applications in biotechnology.

Chairperson: Petri Kursula <petri.kursula@uib.no>, Department of Biomedicine