1. Visualizing open/close switching in individual proteins
Individual SNARE proteins are encapsulated in lipid vesicles and attached to microscope slide.
A custom microscope measures the open-close transitions of each protein molecule using a method called single molecule FRET
0.1 sec/frame
Closed
FRET=1
Open
FRET=1/2
Quartz slide
Biotin
Streptavidin
DMPC
closed
open
Regulatory protein
We measured different open/close switching rates for similar proteins from different species and for mutants of the proteins. Modeling the interactions that determine these switching rate will help us understanding the open/close regulation of SNARE proteins and the impact on controlling neurotransmitter release.
0.3 msec/frame