CRC 858 B04 - Cooperativity within the Dynamic Organisation of Membrane Lipids through Peripher Associated Proteins (SFB 858)

Basic data for this project

Description

The dynamic organization of cellular membranes leading to subdomains with discrete local dimensions and limited lifetime is of fundamental importance for transport processes across membranes and the transmission of biological, chemical and mechanic signals. The organization process is a result of the intrinsic properties of the membrane lipids and of integral or peripherally associated proteins. Among others, proteins associated with the cytosolic leaflet of the plasma membrane, such as annexins, influence the aggregation via interaction with membrane lipids. Annexins support the generation of cholesterol- and PI(4,5)P2-enriched membrane micro domains in model systems and probably also in vivo, i.e. in the cell. Within project B4 the domain formation properties of certain membrane lipids will be analyzed in artificial membrane systems and then in membrane-protein mixtures focussing on the effect of different peripheral (e.g. annexins) and integral membrane proteins. Initial research results suggest a cooperative interaction during the protein-lipid-aggregation process at least for the annexin family member annexin A2. The experiments will be carried out using artificial, solid-supported membranes and a number of high resolution analytical techniques. They will be complemented by a theoretical analysis of membrane domain formation under the different conditions carried out in project B7.