Konishi Kaoru, Uyeda Taro Q P, Kubo Tai
National Institute of Advanced Industrial Science and Technology (AIST), Neuroscience Research Institute, AIST Tsukuba Central 6, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan.
FEBS Lett. 2006 Jun 26;580(15):3589-94. doi: 10.1016/j.febslet.2006.05.037. Epub 2006 May 24.
Kinesin is a linear motor protein driven by energy released by ATP hydrolysis. In the present work, we genetically installed an M13 peptide sequence into Loop 12 of kinesin, which is one of the major microtubule binding regions of the protein. Because the M13 sequence has high affinity for Ca(2+)-calmodulin, the association of the engineered kinesin with microtubules showed a steep Ca(2+)-dependency in ATPase activity at Ca(2+) concentrations of pCa 6.5-8. The calmodulin-binding domain of plant kinesin-like calmodulin-binding protein is also known to confer Ca(2+)-calmodulin regulation to kinesins. Unlike this plant kinesin, however, our novel engineered kinesin achieves this regulation while maintaining the interaction between kinesin and microtubules. The engineered kinesin is switched on/off reversibly by an external signal (i.e., Ca(2+)-calmodulin) and, thus, can be used as a model system for a bio/nano-actuator.
驱动蛋白是一种由ATP水解释放的能量驱动的线性马达蛋白。在本研究中，我们通过基因工程将一段M13肽序列安装到驱动蛋白的12号环中，该环是该蛋白主要的微管结合区域之一。由于M13序列对Ca(2 +)-钙调蛋白具有高亲和力，在pCa 6.5 - 8的Ca(2 +)浓度下，工程化驱动蛋白与微管的结合在ATP酶活性方面表现出陡峭的Ca(2 +)依赖性。植物类驱动蛋白钙调蛋白结合蛋白的钙调蛋白结合结构域也已知能赋予驱动蛋白Ca(2 +)-钙调蛋白调节功能。然而，与这种植物驱动蛋白不同的是，我们新设计的工程化驱动蛋白在维持驱动蛋白与微管相互作用的同时实现了这种调节。工程化驱动蛋白可通过外部信号（即Ca(2 +)-钙调蛋白）可逆地开启/关闭，因此可作为生物/纳米致动器的模型系统。
