Fig. 1: Activity of PKC-1 in NaCl-sensing neuron ASER controls the navigation toward experienced NaCl concentration.
From: Molecular encoding and synaptic decoding of context during salt chemotaxis in C. elegans
a Schematic illustration of the NaCl concentration-learning paradigm4. C. elegans animals are incubated with food at one of the three concentrations of NaCl (100, 50, and 25 mM), and then transferred to an agar plate with gradient of salt concentrations at the start area with ~50 mM of NaCl and allowed to freely migrate. Chemotaxis Index was calculated as indicated based on the numbers of animals in each area at the end of the assay. b Wild-type animals show chemotaxis depending on the NaCl concentration during conditioning, while manipulation of pkc-1 causes altered behaviors showing that PKC-1 functions in the gustatory sensory neuron ASER to determine the direction of migration on the NaCl gradient. n = 6 independent experimental repeats(assays). Error bars indicate SEM. n. s., p > 0.05, ***p < 0.001 in the Tukey’s test (multiple comparisons). c Activation of ASER was observed using GCaMP2.1. The NaCl decrease (50–25 mM) is indicated with a gray shade. n = 20 independent animals. each color represents the strain: gray: N2, magenta: pkc-1(nj3), green: Ex[gcy-5p::pkc-1(gf)]. d Quantification results of (c). p values were calculated by Tukey’s test. The boxes extend from 25th to 75th percentile (first and third quartiles), median is marked by the line, and the ends of whiskers indicate the minimum and maximum values within 1.5× the inter-quartile range from the first and third quartiles, respectively. e An illustration of the model of navigation regulated by DAG/PKC9. When animals are transferred from growth plates to conditioning plates, following calcium influx or efflux in ASER (blue), the amount of DAG (pink) in ASER either increases or decreases, according to the difference in the concentration of NaCl between the growth plate and the conditioning plate. However, after ample conditioning time, the amount of DAG returns to baseline. When worms are transferred from the conditioning plate to the center of the NaCl gradient, DAG either increases or decreases depending on the difference between the NaCl concentration at the conditioning plate and the center of the gradient plate. Increased or decreased DAG regulates the activity of PKC-1, and PKC-1 signals to unknown molecules to regulate unknown neural processes. Source data are provided as a Source Data file.
