Raw data for: Dynamic instability of dendrite tips generates the highly branched morphologies of sensory neurons

Calculation of branch angle: The angle of new branches was measured using the angle tool of ImageJ (zero angle defined as in the direction of the mother). The angle distribution graph was plotted using Prism. Calculation of branch rate: To determine branching events, time-lapse movies of duration 20-30 minutes were analyzed manually using ImageJ. A new protrusion of length >0.25 ?m was scored as a new branch. The total branching rate (min-1) was calculated by dividing the total number of branching events by the total time. The specific branching rate (?m-1min-1) was calculated as the total branching rate divided by the total branch length. The spatial distribution of all branching events was plotted using MATLAB with the soma at the origin (x=0,\ y=0). Analysis of the elongation of internal branches: To study the possible role that the elongation of internal branches in arbor growth, we imaged the same dorsal neurons (A3, A4, and A5) every 24 hrs. Larvae were mounted and imaged as described but without the use of anesthetics. Their movement was minimized by imaging at 4 °C for 2-5 mins. They were then returned to the apple-agar plate in the Darwin Chamber. The larvae were imaged using 20X and 40X objectives. For image analysis, the same neurons at 24 & 48 hr, and 48 & 96hr were segmented and aligned using ImageJ to identify conserved non-terminal internal branches in the proximal region. The fractional increases in branches and segment lengths were defined as" Fractional\ length\ change=\frac{Final\ length-Initial\ length}{Initial\ length}