Absence of actin in the cilia of Tetrahymena pyriformis

An extensive electrophoretic analysis of the proteins of highly purified Tetrahymena pyriformis cilia has been undertaken. No component which would specifically bind rabbit muscle myosin could be identified. Furthermore, no peptides from acetone powders of these cilia could be found which co-electrophoresed with rabbit muscle actin. Lastly, the components which most closely resembled actin in molecular weight were quantitated using densitometry and found to represent less than 0.8% of the tubulin in these preparations.