The Establishment Of Molecular Model Targeting To Microtubule Proteins For Screening The Compounds From Cytotoxic Compounds

Objective The establishment of molecular model targeting to microtubule proteins for screening the compounds from cytotoxic compounds. Methods Microtubule proteins were extracted from fresh porcine brain tissues and purified by ultracentrifugalization, identified by SDS-PAGE, and their concentration was detected by the Bradford assay . The optical density change of microtubule solution which reflected the polymerization-depolymerization status was monitored by the turbidity assay for identification of the function of the normal microtubule proteins. To establish the positive control model by testing the effects of Taxol and Colchicine on microtubule proteins function for the evaluation of the model established and screening active compounds at the same time. The change of ultrastructural morphology of microtubule was detected by the electron microscopy. Results The result of SDS-PAGE showed that the molecular weight of the microtubule proteins prepared was about 55KD agreed with the data reported, the protein concentration ranged from 7.5mg/ml to 20mg/ml. The measurement of microtubule protein polymerization-depolymerization by turbidity assay showed that the microtubule proteins prepared was functional. Positive durgs Taxol and Colchicine promoted and inhibited the polymerization of microtubule, respectively, which consisted with documents reported previously; Eight compounds that could interfere with the kinetics process of microtubule proteins were found; The change of ultrastructural morphology of microtubule by electron microscopy showed that two compounds among eight compounds above could promote the microtubule to polymerize, and other two among them could inhibt the microtubule polymerizing. Conclusion The model established was stable and reliable; Eight active compounds that interfered in the kinetics process of microtubule proteins were found, which suggested that the action on microtubule proteins might be one of cytotoxic mechanisms for their antitumor activity.