Membrane fusion driven by dedicated membrane proteins (SNAREs)
Background:
The fusion of lipid membranes is part of many biological processes, e.g. neurotransmitter release, intracellular vesicle transport, etc. Understanding the heart of membrane fusion is intrinsically related to the question how proteins and lipids communicate in space and time. SNARE proteins were discovered at neuronal synapses but are also essential for fusion of transport vesicles to intracellular organelles or to the plasma membrane of all eukaryotic cells – from yeast to man.
The concept:
Our goal is to uncover the structure/function relationships of recombinant SNARE proteins and of de novo designed fusogenic transmembrane domains. Specifically, we investigate how interaction and conformational flexibility of TMDs contribute to lipid mixing.
We investigate liposome-liposome fusion – as monitored by a FRET-based assay - driven by recombinant SNARE proteins and by synthetic natural and designed TMDs. Artificial fusogenic TMDs (termed 'LV-peptides') are designed from low-complexity sequences containing amino acids of different conformational preference and charge. LV-peptides represent minimal devices driving fusion and thus serve as models to investigate the basic structural requirements of fusogenic proteins.