The Molecular Imaging Center

One of the principal challenges for research in Neuroscience is to elucidate how the nano-scale structural dynamics of proteins - the dynamics that underly these molecules' biochemical function - control signal transmission through neural circuits, ultimately resulting in memory formation and the shaping of perception and behavior. We are setting up imaging facilities that provide real-time visualization of molecular and morphological events (1) in living isolated neurons, (2) in brain slices and (3) in the intact brain. The aim is to provide not only the standard ability to reconstruct in 4-D the shape of cells and the distribution of their molecules at a high temporal and spatial resolution, but to develop methods for the detection of biochemical processes inside cells that are revealed by fluorescent proteins. These proteins are engineered synaptic proteins that generate an optical output during changes in protein-protein interaction or functional conformation. Their optical readout provides a measure of in situ cellular biochemistry and can resolve many of the important cell signaling events, which involve local short-range diffusible signals and changes in protein-protein interaction within membrane-associated protein complexes.

The optical systems of the Molecular Imaging Center - which employ both absolute and ratiometric methods to construct images- are based on four technology platforms: Laser scanning fluorescence confocal microscopy; Deconvolution microscopy; Fluorescent Lifetime Imaging Microscopy (FLIM); and Two-photon fluorescence microscopy.