Directional locomotion of C. elegans in the absence of external stimuli.
Many organisms respond to food deprivation by altering their pattern of movement, often in ways that appear to facilitate dispersal. While the behavior of the nematode C. elegans in the presence of attractants has been characterized, long-range movement in the absence of external stimuli has not been examined in this animal. Here we investigate the movement pattern of individual C. elegans over times of ∼1 hour after removal from food, using two custom imaging set-ups that allow us to track animals on large agar surfaces of 22 cm×22 cm. We find that a sizeable fraction of the observed trajectories display directed motion over tens of minutes. Remarkably, this directional persistence is achieved despite a local orientation memory that decays on the scale of about one minute. Furthermore, we find that such trajectories cannot be accounted for by simple random, isotropic models of animal locomotion. This directional behavior requires sensory neurons, but appears to be independent of known sensory signal-transduction pathways. Our results suggest that long-range directional behavior of C. elegans may not be driven by sensory cues.
Laboratory of Developmental Genetics, The Rockefeller University, New York, New York, United States of America.
Margherita
M
Peliti
John S
JS
Chuang
Shai
S
Shaham
D000818:Animals; D030801:Animals, Genetically Modified; D001522:Behavior, Animal / Q000502:physiology*; D017173:Caenorhabditis elegans / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics* / Q000378:metabolism; D002633:Chemotaxis / Q000502:physiology; D003463:Cues; D005508:Food Deprivation / Q000502:physiology; D015870:Gene Expression; D005838:Genotype; D008124:Locomotion / Q000502:physiology*; D008954:Models, Biological; D009154:Mutation; D010675:Pheromones / Q000172:deficiency / Q000235:genetics; D011984:Sensory Receptor Cells / Q000502:physiology*; D013696:Temperature; D059008:Time-Lapse Imaging; D014741:Video Recording
D029742:Caenorhabditis elegans Proteins; D010675:Pheromones