Genetic dissection of memory for associative and non‐associative learning in Caenorhabditis elegans. (1st November 2012)

• Record Type: Journal Article
• Authors: Lau, H. L.; Timbers, T. A.; Mahmoud, R.; Rankin, C. H.
• Is Part Of: Genes, brain, and behavior. Volume 12:Number 2(2013:Mar.)
• Page Start: 210
• Page End: 223
• Publication Date: 2012-11-01
• Subjects: Behavior genetics -- Periodicals; Neurogenetics -- Periodicals; 616.8
• DOI: 10.1111/j.1601-183X.2012.00863.x
• Languages: English
• ISSNs: 1601-1848

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p> <bold>The distinction between non‐associative and associative forms of learning has historically been based on the behavioral training paradigm. Through discovering the molecular mechanisms that mediate learning, we can develop a deeper understanding of the relationships between different forms of learning. Here, we genetically dissect short‐ and long‐term memory for a non‐associative form of learning, habituation and an associative form of learning, context conditioning for habituation, in the nematode <italic>Caenorhabditis elegans</italic>. In short‐term chemosensory context conditioning for habituation, worms trained and tested in the presence of either a taste (sodium acetate) or smell (diacetyl) context cue show greater retention of habituation to tap stimuli when compared with animals trained and tested without a salient cue. Long‐term memory for olfactory context conditioning was observed 24 h after a training procedure that does not normally induce 24 h memory. Like long‐term habituation, this long‐term memory was dependent on the transcription factor cyclic AMP‐response element‐binding protein. Worms with mutations in <italic>glr‐1</italic> [a non‐<italic>N</italic>‐methyl‐<sc>d</sc>‐aspartate (NMDA)‐type glutamate receptor subunit] showed short‐term but not long‐term habituation or short‐ or long‐term context conditioning. Worms with mutations in <italic>nmr‐1</italic> (an NMDA‐receptor subunit) showed normal short‐ and long‐term memory for habituation but did not show either short‐ or long‐term context conditioning. Rescue of <italic>nmr‐1</italic> in the RIM interneurons rescued short‐ and long‐term olfactory context conditioning leading to the hypothesis that these interneurons function to integrate information from chemosensory and mechanosensory systems for associative learning.</bold> </p> </abstract>