Principal Investigator Michale Fee
To understand brain function at the level of neural circuits, we wish to visualize the activity of many neurons simultaneously, with high temporal resolution. We are developing a genetic approach to this goal based on a new calcium indicator, GCaMP2, that has recently been developed by Dr Junichi Nakai at RIKEN Brain Science Institute. This indicator, consisting of a circularly permuted GFP fused to calmodulin, has been used to image Ca signaling in transgenic mouse heart. We will use this system for monitoring neural activity in vivo, using viral vectors to deliver the transgene reporter to neurons in the song bird nucleus known as HVC. Our goal is twofold: to examine spatio-temporal patterns of activity in HVC during bird song learning (a model for the acquisition of complex motor skills such as speech), and more generally to demonstrate the utility of GCaMP2 as a genetic indicator of neural activity. If successful, we also plan to combine this approach with the use of channelrhodopsin-2 and/or halorhodopsin, which should allow simultaneous optical recording and manipulation of neural activity in vivo.