Syntaxin1A mutations produce general anesthesia resistance and hypersensitivity in larvae. (A) i: Western blot of syntaxin1A protein expression in wild-type (isoCJ1, first lane) and syxH3-C (second lane) larvae, indicating endogenous syntaxin1A protein (red arrowhead) and a smaller deletion protein produced in syxH3-C (black arrowhead). ii: Schematic and timeline of larval anesthesia experiments (see Materials and Methods). After general anesthetic exposure, the position of the larvae is traced on the outside of the glass (blue circles). Larvae that have moved at least one-body-length outside the marked circle are noted (green tick, see Materials and Methods). (B) The proportion of wild-type larvae (isoCJ1) moving after 5 min of anesthetic exposure as a function increasing isoflurane dose is shown. Isoflurane concentrations are shown in μl volumes; see table 1 for corresponding vol% atm. **P < 0.01, t test comparing means to air control (n = 12 experiments per concentration). (C) Average proportion of larvae moving (±SEM) at 3.5 μl isoflurane compared with genetic control (isoCJ1) for syxH3-C (black) and syxKARRAA (gray); syxKARRAA genetic control is syxWT (see Materials and Methods) in the isoCJ1 background. **P < 0.01, t test comparing means (n = 12 experiments per genotype). (D) Average proportion (±SEM) of larvae moving at 2 μl halothane compared with genetic control (isoCJ1) for syxH3-C (black) and syxKARRAA (gray); syxKARRAA genetic control is syxWT (see Materials and Methods) in the isoCJ1 background. *P < 0.05, t test comparing means (n = 12 experiments per genotype).