TABLE 1.

ATPase activity and gliding velocity of C. elegans Myo9 constructs

Mg²⁺-ATPase activity was determined at 20 °C in the absence and presence of 50 μm free Ca²⁺. The gliding velocity of actin filaments was determined at room temperature in the absence and presence of 0.1 mm free Ca²⁺. The errors presented are standard errors calculated from the results of repeated experiments of 3 or 4 independent preparations for the ATPase assay and >7 independent preparations for the actin gliding assay. Dash (–) indicates that no motility was detected.

	Basal	Vmax	Kactin	kapp	Velocity
	s−1	s−1	μm	μm−1s−1	nm s−1
Head/EGTA	0.47 ± 0.01	2.40 ± 0.10	10.38 ± 1.03	0.19	23.81 ± 3.02
Head/Ca2+	0.33 ± 0.02	0.45 ± 0.05	1.08 ± 1.03	0.10	–
Head-4IQ/EGTA	0.13 ± 0.01	0.23 ± 0.03	3.55 ± 2.27	0.03	24.44 ± 4.17
Head-4IQ/Ca2+	0.25 ± 0.01	0.40 ± 0.02	2.06 ± 0.69	0.08	60.07 ± 15.75