Table 1.
Summary of single molecule parameters
| Construct | Track | [KCl] (mM) | Run length (µm)a | Speed (µm/sec)b | N |
|---|---|---|---|---|---|
| Single motor motilityc | |||||
| MyoVc | Actin | 25 | No runs | No runs | 0 |
| MyoVa | Actin | 25 | 0.48 ± 0.02 | 0.48 ± 0.21 | 182 |
| VcVa chimera | Actin | 25 | 0.18 ± 0.004 | 0.54 ± 0.21 | 182 |
| MyoVc | Actin bundles | 25 | 0.49 ± 0.10 | 0.44 ± 0.23 | 207 |
| MyoVc, 37°C | Actin bundles | 25 | 1.26 ± 0.02 | 0.54 ± 0.34 | 206 |
| Multiple motor motilityd | |||||
| MyoVc | Actin | 25 | 0.26 ± 0.02 | 0.13 ± 0.10 | 108 |
| MyoVc | Actin | 150 | No runs | No runs | 0 |
| MyoVc | Actin bundles | 150 | 0.35 ± 0.02 | 0.16 ± 0.13 | 203 |
a
The characteristic run length (λ) was obtained by fitting the cumulative frequency histogram to an exponential function. Error is in standard error of the fit. No runs detected, with a minimum detectable run length of 120 nm.
b
Mean ± SD.
c
Mixing ratios of 1 myosin dimer per 5–10 Qdots ensures that the majority of Qdots are bound by a single motor. Experiments were performed at 1 mM MgATP and 22°C unless specified.
d
Mixing ratios of 10 myosin dimers per 1 Qdot promotes the recruitment of multiple MyoVc motors per Qdot.