我們利用在棘齒板上的模擬系統探討馬達蛋白在微管上的能動性，驅動蛋白和動力蛋白能夠在微管上運送物質，是我們主要探討的對象。微管是生物體中很重要的細胞骨架之一，他的外型就像一個捲曲成管狀的不對稱棘齒板。驅動蛋白及動力蛋白大部分的力學特性可以被成功的重現在棘齒板上。驅動蛋白有三個主要的組成元素：頭部 (head)、頸部 (stalk)和尾端 (tail)，兩個頭部可以幫助驅動蛋白吸附在微管上，頸部是連接頭部和尾端的一個螺旋狀長鏈分子，尾端則負責抓住被運送的物質。我們為驅動蛋白的運動機制提出了一個新的模型，我們利用連接兩個珠鍊環的珠鍊模擬驅動蛋白，根據原子力顯微鏡的觀察，頸部被發現側躺在微管上，我們認為頸部是使驅動蛋白產生力的主要元素。當頸部在微管上做布朗運動時，撞擊管壁產生的力會拉著被吸附的頭往微管的正端走，因為頸部對於落後的頭有較大的力，所以落後的頭有機會受力而翻過領先的頭，形成類似手接手模型 (hand-over-hand model)中的運動。另外，尺蠖式 (inchworm type)的運動在我們的模型中也是有機會發生的。
　　動力蛋白中主要的元素為AAA環 (AAA ring)、長鍊區 (stalk)及長尾區 (stem)，AAA環為動力蛋白的主體，長鏈區的尾端有一個球狀的區域可以吸附在微管上，而長尾區藉由連結區 (linker)與AAA環連接，可以抓住要運送的物質。在我們的模型中，動力蛋白在微管上的運動是源自於其linker與微管的碰撞，連結區是在動力蛋白中被認為與其運動相關的元素。我們利用貼上一個細桿的壓克力環模擬動力蛋白，在模擬系統中我們能夠重現許多動力蛋白在真實系統中的行為表現，如：微管上的雙向步進運動、運動速度與受力的關係和三磷酸腺苷 (ATP)濃度對速度的影響。這種利用棘齒板上的模擬系統探討蛋白馬達行為的方法可以克服一些技術上的困難，並提供可與真實系統對照的結果。

　　The motilities of microtubule-based motor proteins, kinesin and dynein, are investigated with vibrating ratchet-based simulation systems. These two motor proteins are reported being able to transport cargos along microtubule. Most dynamic features are established with reasonable explanations for the simulating kinesin and dynein on the asymmetric ratchet plate which is similar to the outer surface of microtubule. Kinesin motor is composed of the head domain binding to microtubule, the tail domain holding cargos, and the stalk domain connecting the two heads and the tail domains. We propose a new dynamic model for kinesin. According to the recent AFM results that the stalk domain lies sideward to on microtubule, we consider the force is generated by the randomly moving stalk on microtubule. The force produces greater tension on the trailing head than the leading head. The trailing head can be randomly triggered to flip over the leading head, processing a similar hand-over-hand motion. Otherwise, the inchworm type of motion is also possible under the influence of stochastic force.
　　As for dynein, in our model, the force is believed to be originated from the collision between the linker and the outer surface of microtubule. The bidirectional motion, processive stepping, the velocity-force relation, and the ATP concentration dependence of velocity for dynein on microtubule are demonstrated with the simulation system. The ratchet-based simulation systems for microtubule-based motor proteins give an alternative approach to investigate the motility of kinesin and dynein.

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