F-ACTIN IDENTIFICATION USING PHALLOIDIN COLLOIDAL GOLD - 1 - BIOCHEMICAL PREPARATIONS

A modification of the well-known method of ''polymerization-depolymeri zation'' was used for obtaining preparations enriched in plant actin f rom roots of wheat (Triticum aestivum L., cv. Saratovskaya 29) seedlin gs and the endocarp of immature tomato (Lycopersicon esculentum Mill.) fruits. These preparations were characterized biochemically and under an electron microscope. F-actin identification in these preparations on the basis of the protein mol wt and its interaction with a specific marker for polymeric actin phalloidin-colloidal gold permitted us to con dude that polymerization-depolymerization was an adequate procedur e for the production of actin-enriched fractions from plant tissues. T he preparations of plant and animal actins were compared with regard t o filament formation in vitro and the mode of their labeling with phal loidin-colloidal gold. The conclusion was drawn that this marker could be used at all stages of plant actin purification, including rapid qu antification of F-actin in preparations of various purity.