Fig 3.
skn-1 is expressed in AIY neurons and regulates their functions. (A) Schematic of the neuronal circuits of C. elegans chemoattractive andthermotactic behaviors. Green triangles represent sensory neurons and blue hexagons command interneurons. Arrows indicate direct interactions,and their thickness is proportional to the frequency of synaptic contacts between the neurons (Adapted from [36]). T, thermophilic; C, cryophilic.(Adapted from [41]). (B) Population thermotaxis experiments were performed using a radial thermal gradient. After 60 minutes the position of theworms was scored and the percentages of worms in the colder (Zone 1) and warmer (Zone 2) regions determined. N2 animals moved toward theregion of the plate closer to their previous cultivation temperature (23C), while both
skn-1 null strains
zu135 and
zu67 showed a cryophilic phenotypesimilar to
ttx-3 (AIY) null worms. (C) Representative 3D reconstruction of confocal sections through the head region of double transgenic wglS342;otlS133 worms is shown. The
skn-1:EGFP reporter (green), containing the entire
skn-1 gene, is highly expressed in neurons in the head ganglia, andcolocalizes with the AIY-specific marker
ttx3:RFP (Red). Arrows point at AIY. Scale bar 10 um. (D) Relative mRNA levels of the AIY cell fatespecification homeobox genes
ttx-3 and
ceh-23, and their targets
ser-2a,
ser-2b,
sra-11,
kal-1 and
hen-1 in N2 and
skn-1 null worms. (E)Representative 3D reconstructions showing the expression of the transcriptional reporter
ser2:prom1:EGFP in the head region of N2 and
skn-1(
zu135)null worms. Data are mean and S.E.M. of 3-5 experiments. *p<0.05; **p<0.01; ***p<0.001 versus N2 (Student's t-test).