Abstract
Abstract The purpose of this thesis is to analyze the spatiotemporal odor coding on mushroom body (MB) sectors in Drosophila brain with all-in-focus microscopy. Regarding to odor coding on MB, most previous studies focus on sparse coding of Kenyon cells, which represent odor by spatially firing on cells. However, the mechanism of olfactory information processing in the temporal domain has not been studied yet, which is believed to provide more detailed information. Here a tunable acoustic gradient-index (TAG) lens is combined with conventional two-photon microscope allowing three-dimensional monitoring of all MB sectors within several milliseconds. To analyze initially firing time of GCaMP6f on MB sectors, a sigmoidal function fitting method is adopted. In this study, the neural firing initial time on MB sectors show spatiotemporal property and the spatiotemporal patterns change with distinct odors. However, this spatiotemporal pattern eliminates when down-regulating the expression of Rdl protein in Kenyon cells, which the four sectors respond to an odorant stimulus in a synchronized manner compared with α1/α′1. This study reveals that the dynamic odor responses among MB sectors contain olfactory information.