TUBULIN ASSOCIATIONS AND EFFECTS OF ANTICANCER DRUGS

拟议研究的目的是为了达成一项详细的理解。 对分子(和亚分子)水平上的机理有多确定 抗有丝分裂药物与微管蛋白结合并诱导其发生聚合 每种情况下对特定结构的反应。待研究的药物 秋水仙碱、长春花碱和紫杉醇及其类似物和 衍生物和与部分络合物相对应的较小分子 药物结构。具体地说，药物结合和 微管蛋白的自结合或构象变化将被表征 通过严格的热力学和动力学方法。两者之间的联系 同一药物分子不同部位与微管蛋白的相互作用 通过使用小分子进行检查，如长春花碱和泻药 长春花碱的案例。的绑定的相互影响 个别药物的相互作用之后将是热力学和 表征协作性的构象技术(积极的，如 在秋水仙碱-长春花碱中，或在秋水仙碱-紫杉醇中为阴性)，其 存在于它们的绑定中。药物结合部位的相对位置 微管蛋白分子及其与其他分子结合引起的位移 通过测量药物和药物之间的距离来确定药物 微管蛋白上的参考点，如可交换位点GTP，以及 药物分子和这些分子的一部分之间。这些距离将 用核磁共振、电子顺磁共振和荧光能量转移等方法进行测定。为了这个 用途，适当的氟化、自旋标记和荧光标记 基团将被引入药物的结构和他们的 类比。所使用的方法将是那些大分子物理方法 生物化学，包括沉淀法、荧光分光光度法、密度法、 定量凝胶层析、光散射、电泳、傅里叶变换 变换红外光谱、圆二色谱、核磁共振和电子顺磁共振 作为化学修饰和合成。这项研究的目的是为了 对某些抗癌药物的作用方式的理解 它们的功能是希望识别出将 在新的此类药物的设计中是有用的。(L)

The aims of the proposed research are to arrive at a detailed understanding of the mechanism on the molecular (and submolecular) level of how certain anti-mitotic drugs bind to tubulin and induce it to undergo polymerization reactions to particular structures in each case. The drugs to be studied are colchicine, vinblastine and taxol, as well as their analogs and derivatives, and smaller molecules which correspond to parts of the complex drug structures. Specifically, the linkages between drug binding and self-association or conformational changes of tubulin will be characterized by rigorous thermodynamic and kinetic approaches. The linkage between the interactions of different parts of the same drug molecule with tubulin will be examined by using small molecules, such as vindoline and catharantine in the case of vinblastine. The mutual effects of the binding of the individual drugs on each other will be followed by thermodynamic and conformational techniques to characterize the cooperativity (positive, as in colchicine-vinblastine, or negative as in colchincine-taxol) which exists in their bindings. The relative locations of the drug binding sites on the tubulin molecule and their shifts induced by the binding of other drugs will be determined by measuring distances between the drugs and a reference point on tubulin, such as the exchangeable site GTP, as well as between drug molecules and parts of these molecules. These distances will be measured by nmr, epr and fluorescence energy transfer methods. For this purpose, appropriate fluorinated, spin-labelled and fluorescent marker groups will be introduced into the structures of the drugs and their analogs. The methods used will be those of macromolecular physical biochemistry, including sedimentation, spectrofluorimetry, densimetry, quantitative gel chromatography, light scattering, electrophoresis, Fourier transform infra-red spectroscopy, circular dichroism, nmr and epr, as well as chemical modification and synthesis. This research is aimed at an understanding of the manner in which certain anti-cancer drugs perform their function with the hope of identifying structural features which will be useful in the design of new such drugs. (L)