(A) (Top) Schematic of worm head indicating positions of sensory neuron soma. Boxed area is shown in images below. (Below) Representative images of ins-26p::yfp and ins-35p::yfp expression in fed wild-type and cmk-1(oy21) mutants. White and yellow arrowheads indicate ASI and ASE, respectively; white arrow indicates AWC; yellow asterisk marks expression in the intestine. The location of ASK is indicated by a red arrowhead; fluorescence in ASK is weak and not visible at this exposure in shown images. Lateral view; scale bar: 10 μm. (B) Quantification of expression in each neuron type in fed and starved (>6 hr) conditions. Solid and hatched bars indicate strong and weak expression, respectively, in each cell. n > 50 animals each; three independent experiments. (C) Dauers formed by shown strains on 160 μg heat-killed OP50 and 60 nM ascr#2 (left), and 80 μg live OP50 and 6 μM ascr#3 + 600 nM ascr#5 (right). Alleles used were: ins-26(tm1983), ins-35(ok3297) and ins-32(tm6109). n > 4 assays of 65 animals each; at least three independent experiments. (D) Dauers formed by shown strains on 6 μM ascr#3 and 80 μg live OP50. ins-26 and ins-35 cDNAs were expressed in ASE, ASJ, and AWC under che-1, trx-1, and ceh-36∆ regulatory sequences, respectively. At least two independent lines were analyzed for each transgenic strain. Shown are the averages of at least three independent experiments with >65 animals each. (E) Scatter plot of fluorescence intensity of daf-28p::gfp expression in ASJ in the indicated genetic backgrounds. ins-26 and ins-35::SL2::mCherry cDNAs were expressed in AWC under the odr-1 promoter. Only animals expressing mCherry in AWC were scored. Median is indicated by red horizontal line. Each dot is the fluorescence intensity of a single neuron in a given experiment. n > 60 neurons total each, four independent experiments. (F) Quantification of dauer formation in AWC-ablated animals in the presence of 6 μM ascr#3 and the indicated amounts of heat-killed (blue circles) or live (red circles) OP50. Each filled circle represents one assay; n > 65 animals per assay, five independent experiments. Line represents best fit to the data. Dashed line indicates the curve for wild-type animals from Figure 1B shown for comparison. *, **, and *** indicate different from values using 160 μg of heat-killed bacteria at p < 0.05, 0.01, and 0.001, respectively. (G) Dauers formed by the indicated strains on 80 μg live OP50 and 6 μM ascr#3. For each assay: n > 65 animals; four independent experiments. Errors are SEM. Except where indicated, *, **, and *** indicate different from wild-type at p < 0.05, 0.01, and 0.001, respectively; #, ##, and ### indicate different from cmk-1(oy21) at p < 0.05, 0.01, and 0.001, respectively (ANOVA and Games-Howell post-hoc test).