Contextual Taste Cues Modulate Olfactory Learning in C. elegans by an Occasion-Setting Mechanism

Law, Eric; Nuttley, William M.; Kooy, Derek van der

doi:10.1016/j.cub.2004.06.066

Cited by 28 publications

(31 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…It has been reported that gpc-1 is involved in salt chemotaxis plasticity ( Jansen et al 2002), while no olfactory adaptation defect was observed in gpc-1 mutants ( Jansen et al 2002;Law et al 2004). Thus, this is the first report that C. elegans gpc-1 is involved in olfactory adaptation.…”

Section: Resultsmentioning

confidence: 53%

GPC-1, a G Protein γ-Subunit, Regulates Olfactory Adaptation in Caenorhabditis elegans

et al. 2009

View full text Add to dashboard Cite

Caenorhabditis elegans genome carries two Gg genes, gpc-1 and gpc-2, and two Gb genes, gpb-1 and gpb-2. Of these, gpc-2 and gpb-1 are expressed ubiquitously and are essential for viability. Through a genetic screen, we identified gpc-1 as essential for olfactory adaptation. While wild-type animals show decreased chemotaxis to the odorant benzaldehyde after a short preexposure to the odorant, gpc-1 mutants are still attracted to the odorant after the same preexposure. Cell-specific rescue experiments show that gpc-1 acts in the AWC olfactory neurons. Coexpression of GPC-1 and GPB-1, but not GPB-2, caused enhanced adaptation, indicating that GPC-1 may act with GPB-1. On the other hand, knock down of gpc-2 by celltargeted RNAi caused reduced chemotaxis to the odorant in unadapted animals, indicating that GPC-2 mainly act for olfactory sensation and the two Gg's have differential functions. Nonetheless, overexpression of gpc-2 in AWC neurons rescued the adaptation defects of gpc-1 mutants, suggesting partially overlapping functions of the two Gg's. We further tested genetic interaction of gpc-1 with several other genes involved in olfactory adaptation. Our analyses place goa-1 Goa and let-60 Ras in parallel to gpc-1. In contrast, a gain-of-function mutation in egl-30 Gqa was epistatic to gpc-1, suggesting the possibility that gpc-1 Gg may act upstream of egl-30 Gqa.

show abstract

Section: Resultsmentioning

confidence: 53%

GPC-1, a G Protein γ-Subunit, Regulates Olfactory Adaptation in Caenorhabditis elegans

et al. 2009

View full text Add to dashboard Cite

show abstract

“…Following odorant habituation, expression of the learned behavior can be modulated by contextual cues present during conditioning. Law et al (2004) found that worms exposed to an odorant in the presence of a taste cue showed enhanced retention of olfactory habituation when challenged in the presence of that same cue (Law et al 2004). Furthermore, Bettinger and McIntire (2004) demonstrated that worms previously adapted to an odorant under the influence of ethanol displayed decremented responses to that odorant only when intoxicated.…”

Section: Effect Of Context On Chemosensory Habituationmentioning

confidence: 99%

An elegant mind: Learning and memory in Caenorhabditis elegans

Ardiel¹,

Rankin²

2010

Learn. Mem.

281

191

View full text Add to dashboard Cite

This article reviews the literature on learning and memory in the soil-dwelling nematode Caenorhabditis elegans. Paradigms include nonassociative learning, associative learning, and imprinting, as worms have been shown to habituate to mechanical and chemical stimuli, as well as learn the smells, tastes, temperatures, and oxygen levels that predict aversive chemicals or the presence or absence of food. In each case, the neural circuit underlying the behavior has been at least partially described, and forward and reverse genetics are being used to elucidate the underlying cellular and molecular mechanisms. Several genes have been identified with no known role other than mediating behavior plasticity.Historically, it was believed that even if they were capable of learning, the nervous systems of invertebrates were too different to be instructive on human cognition. In the 1960s, Kandel and colleagues began studying learning in the marine mollusc Aplysia (Kandel and Tauc 1965). Using this system, they were able to relate behavioral plasticity to changes at specific synapses of identified neurons, and began a biochemical analysis of these neuronal changes, uncovering a role for cAMP, PKA, and CREB. In the 1970s, Benzer and colleagues began a genetic dissection of learning in the fruit fly Drosophila melanogaster (Quinn et al. 1974;Dudai et al. 1976). They established an associative learning assay (Quinn et al. 1974) and conducted a forward genetic screen, identifying the first learning mutant, dunce (Dudai et al. 1976). Since then, many genes have been cloned, and the biological basis of learning has proven to be highly conserved (Barco et al. 2006;Skoulakis and Grammenoudi 2006). Today there is no question as to the relevance of invertebrate research in the field of learning and memory.At about the same time that Kandel was beginning his work with Aplysia, Sydney Brenner chose Caenorhabditis elegans as the organism in which to study development and the nervous system (Brenner 1974). Today this transparent nematode is the world's best understood animal. It's small size ( 1 mm), short life cycle (,3 d), and ease of cultivation make it perfect for the laboratory, and its mode of reproduction is ideal for genetic analysis-selffertilizing hermaphrodites can be easily inbred or crossed with males. The genome has been mapped and sequenced, and there are thousands of mutants and RNAi constructs readily available for researchers. Furthermore, C. elegans has an invariant cell lineage and relatively simple morphology-959 cells make up the entire adult hermaphrodite (Sulston and Horvitz 1977;Sulston et al. 1983). Using serial section electron micrographs, White et al. (1986) were able to construct a neural wiring diagram of the hermaphrodite's 302 neurons. They found about 5000 chemical synapses, 600 gap junctions, and 2000 neuromuscular junctions, the location of which were fairly consistent between animals. With its invariant cell lineage and reproducible connectome, C. elegans was initially viewed as a genetically hardwired ...

show abstract

“…Anderson et al (Anderson et al, 2007) assayed thermotaxis on a steeper gradient than we did, and both prior studies (Anderson et al, 2007;Jurado et al, 2010) used assay plates comprised of different media than the NGM agar plates on which the worms were reared, which might have led to a contextspecific association of food, temperature and medium. Such circumstances could potentially change the association of food and temperature, and block thermophilic behaviour in some assay conditions (Law et al, 2004).…”

Section: Variation Within C Elegans For Temperature-dependent Behaviourmentioning

confidence: 99%

Temperature-dependent behaviours are genetically variable in the nematode Caenorhabditis briggsae

Stegeman

Mesquita

Ryu

et al. 2012

Journal of Experimental Biology

View full text Add to dashboard Cite

SUMMARY Temperature-dependent behaviours inCaenorhabditis elegans, such as thermotaxis and isothermal tracking, are complex behavioural responses that integrate sensation, foraging and learning, and have driven investigations to discover many essential genetic and neural pathways. The ease of manipulation of the Caenorhabditis model system also has encouraged its application to comparative analyses of phenotypic evolution, particularly contrasts of the classic model C. elegans with C. briggsae. And yet few studies have investigated natural genetic variation in behaviour in any nematode. Here we measure thermotaxis and isothermal tracking behaviour in genetically distinct strains of C. briggsae, further motivated by the latitudinal differentiation in C. briggsae that is associated with temperature-dependent fitness differences in this species. We demonstrate that C. briggsae performs thermotaxis and isothermal tracking largely similar to that of C. elegans, with a tendency to prefer its rearing temperature. Comparisons of these behaviours among strains reveal substantial heritable natural variation within each species that corresponds to three general patterns of behavioural response. However, intraspecific genetic differences in thermal behaviour often exceed interspecific differences. These patterns of temperature-dependent behaviour motivate further development of C. briggsae as a model system for dissecting the genetic underpinnings of complex behavioural traits. Supplementary material available online at

show abstract

Contextual Taste Cues Modulate Olfactory Learning in C. elegans by an Occasion-Setting Mechanism

Cited by 28 publications

References 18 publications

GPC-1, a G Protein γ-Subunit, Regulates Olfactory Adaptation in Caenorhabditis elegans

GPC-1, a G Protein γ-Subunit, Regulates Olfactory Adaptation in Caenorhabditis elegans

An elegant mind: Learning and memory in Caenorhabditis elegans

Temperature-dependent behaviours are genetically variable in the nematode Caenorhabditis briggsae

Contact Info

Product

Resources

About