Vanderbilt Summer Science Academy

Neuronal Cultures with Parvalbumin (PV)-dependent Expression of the tdTomato Fluorescent Protein as a Model System to Study Injury to PV Fast-Spiking GABAergic Interneurons

Coordinated firing and circuit activation of essentially all excitatory neurons is under the control of parvalbumin-positive (PV), fast-spiking inhibitory interneurons. Damage to PV neuron structure and function, as seen in patients with schizophrenia and Alzheimer’s Disease (AD), can result in diminished information processing, memory formation, and learning capabilities. The application of injury to these fast-spiking neurons can modify the expression of PV within the cell or result in cell death. Until very recently, it has been difficult to distinguish between these two situations because the identity of PV neurons has only been confirmed by expression of PV. Through utilization of PV-Cre:Rosa26-tdTomato (VTD) mice, I will be able to characterize the maturity of cortical neuronal cell cultures over time monitoring the expression of the fluorescent tdTomato protein. The comparison of immunofluorescent staining for PV in non-transgenic cultures and VTD cultures will show the time course of PV expression in the fast-spiking cells in relation to the expression of the tdTomato fluorescence. A confocal microscope will be used to image the immunofluorescence of PV and tdTomato proteins. The images will then be further analyzed using MetaMorph and GraphPad Prism to produce quantitative data that represents my findings. From this experiment, I expect to learn the developmental timing of PV and tdTomato protein expression in PV neurons. These results will be important to subsequent studies in determining why PV neurons are especially vulnerable to injury in aging as well as AD and could allow us to develop treatments to protect these neurons.