Figure 6

Quantification of body peristaltic contractions of freely crawling Drosophila larvae. The results of two trajectories traced with LACE are shown in (A–C): (A) the curvature, (B) eccentricity, and (C) normalized body length of a wild-type (CantonS) larva (orange) and a nan^36a mutant larva (blue). The curve finder (A) detects portions of the video where turning is detected. The turns appear as gray shaded areas (point 2 for CantonS and points 2 and 3 for nan^36a). The white background shows peristaltic contractions during forward crawling (points 1 and 3 for CantonS and 1 for nan^36a). Above (wildtype) and below (nan^36a) still frames from the corresponding times (1,2,3) are depicted. The pseudo-skeleton is superimposed as a light blue line, the contour of the animal is shown as solid green line, the central contour as a dashed green line, and the gut as a red line. Both markers (gut, central contour) were not used in this analysis. In (D) the contraction amplitude is quantified for wildtype, w¹¹¹⁸ , nan^36a and iav¹ mutant larvae. The nan^36a and iav¹ mutants have significantly lower body contraction amplitudes compared to wildtype CantonS and w¹¹¹⁸. The dataset consists of 30 wildtype larvae (CantonS), 26 w¹¹¹⁸ larvae, 8 nan^36a larvae, and 12 iav¹ larvae. Statistical significance was tested with Fisher's permutation test on different medians. ***p < 0.001, **p < 0.01.