Table I. Physical parameters of melanophore motion.
| Long distance constant D
L, minus end |
Number ratio N
SL, minus end |
X
V
2, P(X
V
2), minus end motion |
Long distance constant D
L, plus end |
Number ratioN SL, plus end |
X
V
2, P(X
V
2), plus end motion |
|
|---|---|---|---|---|---|---|
| nm | nm | |||||
| Wild-type dispersion |
519 ± 67 | 0.29 ± 0.22 | 0.42, 0.96 | 665 ± 46 | 0.25 ± 0.20 | 0.41, 0.95 |
| Wild-type aggregation |
1,206 ± 200 | 0.16 ± 0.12 | 0.95, 0.42 | 845 ± 118 | 0.11 ± 0.08 | 0.71, 0.69 |
| Dominant negative myosin V dispersion |
974 ± 117 | 1.25 ± 1.06 | 0.67, 0.80 | 831 ± 43 | 0.65 ± 0.43 | 0.32, 0.99 |
| Latrunculin dispersion |
1,318 ± 206 | 1.12 ± 0.48 | 0.74, 0.85 | 1,180 ± 150 | 0.55 ± 0.30 | 0.86, 0.72 |
| Dominant negative myosin V aggregation |
1,284 ± 150 | 0.16 ± 0.14 | 1.12, 0.30 | 876 ± 145 | 0.15 ± 0.09 | 1.31, 0.15 |
Melanosome motion was characterized by tracking analysis. The distance constant D L was found by fitting histograms of travel distance, D, to the sum of two exponential functions: y(D) = exp(−D/D s) 1 A L exp(−D/D L). D S did not vary appreciably, with an approximate value in all cases of ∼130 ± 40 nm. The long distance constant D L is an estimate of mean run length of long runs because for a decaying exponential the decay constant is identical to the average travel distance. The number ratio N SL is the number of short runs divided by the number of long runs and thus measures the relative frequency of the two travel states. The X V 2 values (with corresponding probabilities) indicate the goodness of the fit.