NCS-1 with deletion of its C-terminal tail is still able to rescue the temperature-dependent changes in locomotion. (A) Model structure of C. elegans NCS-1 derived from the solution NMR structure of human NCS-1(2LCP) indicating the C-terminal deletions tested in this study. The figure shows the C-terminal part of NCS-1 (from residue 95) with the C-terminal pocket of its hydrophobic groove occupied by its C-terminal tail and with the C-terminus indicated by C. The tail and increasing amounts of the preceding helix are deleted in the mutants ∆177-191, ∆174-191 and ∆169-191. V125 is shown in red. (B) Locomotion rates of wild-type Bristol N2, ncs-1 null (qa406), wild-type rescue or C-terminal deletion expressing transgenic worms were assayed at room temperature (20°C; open bars) and then after elevation of temperature to 28°C for 10 min (filled bars). For each deletion mutant locomotion of three separate lines of transgenic worms was assayed, the data from separate worm lines pooled and the data from experiments on different days normalised to the locomotion rate of N2 worms at 20°C in that particular assay. The rate of movement at 20°C and 28°C was compared for each condition (*; P < 0.01, n = 15-30 worms). Statistical significance was determined using the Mann–Whitney U test with use of the Bonferonni correction for multiple comparisons.