中文摘要
本研究的目的是利用全焦距顯微鏡分析果蠅蕈狀體上嗅覺信息的時間與空間關係。目前對果蠅蕈狀體的研究主要關注在蕈狀體的形態、神經細胞之間的連接以及蕈狀體在果蠅的學習和記憶中扮演的角色。但是，在蕈狀體軸突部分，關於嗅覺信息處理的時間機制尚未清楚，對此進行研究會為果蠅蕈狀體嗅覺信息處理提供更多信息。
我們採用可調節焦距鏡頭與傳統雙光子顯微鏡結合的方式，實現在幾個毫秒以內對果蠅蕈狀體三維掃描。為了分析果蠅蕈狀體上五個區域神經活動的時間關係，本文採用S型函數去處理功能性影像數據得到蕈狀體上不同分區的鈣離子激發螢光訊號變亮的初始時間。結果顯示在MCH味道刺激下，果蠅蕈狀體5個分區上鈣離子螢光蛋白變亮的初始時間不同。對於同一株果蠅，在MCH味道和OCT味道刺激下，蕈狀體不同區域上鈣離子螢光蛋白變亮的順序不同。然而，通過Rdl-RNAi抑制Rdl蛋白質在kenyon細胞的表達使得神經活動時間順序變得相同。

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.

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