Fig. 4

Quantitative analysis of neurite dynamics. (A) Average of stable (present throughout the six time frames) versus transient (present in fewer than six time frames) neurites in wild-type and tmie mutant fish. Error bars represent the s.e.m. *, P<0.01. (B) Neurite persistence. Persistence of neurites was calculated from the percentage of neurites present for only one, two, three, four, five or all six time frames. (C) Neurite consistency. ‘Consistent’ refers to a neurite that has neither grown nor retracted over the six time frames. ‘One event’ refers to a neurite that has only grown or retracted over the six time frames. ‘Two events’ refers to a neurite that completed a sequence of two counter movements, i.e. growth followed by retraction or vice versa. Similarly, ‘three events’ refers to a sequence of three counter movements. (D-F) Dynamics of neurites tips. The value of the terminal point position at the first time point was normalized to zero and the same value was subtracted from the subsequent time points in order to establish the distance traveled by the neurite tip. On the right of each graph is shown the average distance (µm) traveled by each type of neurite during one time frame. Stable neurites lack a bulged extremity but are present throughout the six time frames. (D) Dynamics of bulged neurites. (E) Dynamics of stable non-bulged neurites. (F) Dynamics of transient neurites. Red lines, wild type; dashed green lines, tmie. Error bars represent s.e.m. *, ***, ****, P<0.01; **, P<0.1 for pairs indicated by number of asterisks; wild type, n=6; tmie, n=6.