神經是高度特化的極性細胞，具有樹突以及單一長軸突。許多蛋白質在神經元的細胞體中合成，並形成突觸囊泡，經由樹突以及軸突運輸至突觸。此種運輸方式須藉由分子馬達dynein以及kinesin將化學能轉換為機械能量，於神經維管上移動所完成。然而，神經細胞內運輸物的運輸機制尚未完全了解，其中一個重要的問題為運輸物的雙向運動是由何種訊息所誘發? 其中一個被廣為接受的假設是一個運輸物上結合許多分子馬達，並透過協調作用活化以及去活化這些分子馬達，或是透過拔河作用來調控此雙向運動行為。UNC-104/KIF1A是神經專一性的kinesin，負責在神經軸突維管上運輸突觸囊泡前驅物，在神經維管上能觀察到其頻繁的雙向運動。我們假設此種雙向運輸是來自dynein於另一方向的拉力，因此，在這篇研究中，我們利用秀麗隱桿線蟲觀察dynein和dynactin突變的情況下，UNC-104的運輸情形。有趣的是，我們發現當dynein突變時，UNC-104往anterograde方向的運輸不受影響，因此推測UNC-104與dynein是透過協調機制調控突觸囊泡的雙向運輸。然而，UNC-104往retrograde方向的運動長度以及持續時間在dynein heavy chain-1 (dhc-1)突變之下，有顯著地增加，推測UNC-104或是一些輔助蛋白與DHC-1有交互作用，而干擾dynein的運動。進一步比較UNC-104和synaptobrevin (SNB-1，一種突觸囊泡蛋白)的運動模式，我們推測有其他的kinesin參與突觸囊泡的運輸。另一方面，dynactin p150次單位(線蟲中為dnc-1)的突變導致UNC-104往anterograde方向的運動長度以及持續時間增加，綜合其它文獻後推測，DNC-1可能透過與UNC-104間的交互作用來調控UNC-104的運輸。最後，觀察UNC-104和SNB-1的運動模式，我們推測在突觸囊泡的運輸中，DNC-1扮演很重要的輔助角色。

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