Active sliding movement of latex beads coated with skeletal muscle myosin onChara actin bundles

Summary Latex beads coated with rabbit skeletal muscle myosin were introduced by intracellular perfusion intoChara cells from which the tonoplasts had been removed. Mg · ATP dependent movement of the beads along files ofChara chloroplast layers was observed. The movement was in opposite directions on the two sides of the indifferent line, indicating that the movement was dependent on the polarity of the actin bundles. This suggests that the unknown factor responsible for generating the motive force for cytoplasmic streaming inChara endoplasm is myosin. The advantages of the present experimental system for studying the sliding mechanism of actomyosin are discussed.Abbreviations APW artificial pond water - ATP adenosine 5-triphosphoric acid - DTT dithiothreitol - EDTA ethylenediamine tetraacetic acid - EGTA ethyleneglycol-bis(-aminoethyl ether)N, N, N, N-tetraacetic acid - HMM heavy meromyosin - LMM light meromyosin - NEM N-ethylmaleimide - PIPES piperazine-N, N- bis(2-ethanesulfonic acid)