Purification and characterization of tubulin from ginkgo pollen

 Tubulin was purified by a combination of acetone powder preparation, DEAE Sephadex A-50 chromatography, Sephacryl S-300 gel filtration, and Mono Q anion exchange chromatography from the pollen of ginkgo (Ginkgo biloba L.), a typical gymnosperm. The average yield of tubulin is 2 mg per 100 g of pollen grain. The purified tubulin is electrophoretically homogeneous. It seems to be composed of two subunits on SDS-PAGE and is resolved as two major spots on two-dimensional electrophoresis, preliminarily indicating that there are no obvious tubulin isotypes in ginkgo pollen. The apparent molecular weights of the two subunits are about 54 kDa and 52 kDa respectively, estimated from the SDS-PAGE. It was also demonstrated that tubulin from ginkgo pollen is immunochemically related to animal brain tubulin, and the purified tubulin was polymerized to microtubular aggregates in the presence of taxol and GTP in vitro. Received: 13 April 1996 / Revision accepted: 24 March 1997