ATP concentration dependency of the tubule-extrusion velocity from the axonemes

ATP-driven tubule-extrusion from trypsintreated axonemes of sea urchin sperm flagella was induced by adding ATP. Using a CTC-9000 Night Vision Camera system including a video tape recorder, velocity of the tubule-extrusion process was measured and found to increase with increasing ATP concentration. Minimum concentration of ATP inducing the tubule-extrusion was around 4 μM. The velocity at 18–22 °C was around 1.8 μm/sec at 10 μM ATP and 6.6 μm/ sec at 1 mM ATP.