Olfactory transduction

The sensitivity of the olfactory system is likely to derive from the capacity of the olfactory transduction apparatus to effectively amplify and rapidly terminate signals 821... 

Odorant recognition initiates a second-messenger cascade leading to the depolarization of the neuron and the generation of action potentials 821 Negative-feedback processes mediate adaptation of the olfactory transduction apparatus to prolonged or repetitive stimulation 823 Alternative second-messenger pathways maybe at work in olfactory transduction 823... 

Alternative second-messenger pathways may be at work in olfactory transduction. The role of cAMP in olfactory transduction is well established. Are there alternative pathways, such as those involving phospholipids and Ca2+ Several groups have reported that certain odorants can elicit an increase in the phosphoinositde second messenger inositol 1,4,5,-trisphosphate (IP3) (Ch. 20). However, there is no clear evidence that IP3 directly mediates an electrical response in OSNs, nor is there a clear rationale for two parallel excitatory odor transduction cascades. However, more recent data support the idea that phos-phoinositides or enzymes related to their metabolism may play a modulatory role, shaping the OSN output by... 

Kurahashi, T. and Yau, K. W. Olfactory transduction. Tale of an unusual chloride current. Curr. Biol. 4 256-258,1994. 

Olfactory Transduction in Pheromone-Specific Receptor Cells... 

Ache, B. W. and Zhainazarov, A., Dual second-messenger pathways in olfactory transduction, Curr. Op. Neurobiol., 5, 461, 1995. 

Vanderwel D. and Oehlschlager A. C. (1987) Biosynthesis of pheromones and endocrine regulation of pheromone production in Coleoptera. In Pheromone Biochemistry, eds G. J. Blomquist and G. D. Prestwich, pp. 175-215. Academic Press, Orlando, FL. Villet R. H. (1974) Involvement of amino and sylfhydryl groups in olfactory transduction in silkmoths. Nature 248, 707-709. 

BreerH., Boekhoff I. andTareilus E. (1990a) Rapid kinetics of second messenger formation in olfactory transduction. Nature 345, 65-68. 

It would seem that none of the mutations in potentially important elements of olfactory transduction has led to clear ideas about the transduction mechanisms employed by Drosophila ORNs. It may be that different neurons employ slightly different mechanisms expressing different genes, but there is no direct evidence for interacting pathways in single ORNs. 

The information reported here is a transcript of a lecture givoi by S. Firestcin on cyclic nucleotide gated channels in olfactory transduction. See abstracts of a symposium at the occasion of the the 40th anniversary of the Unilever research labcaatory in Vlaardingm, Tbe Netherlands, 1996.)... 

Caged cAMP has been particularly useful in neuroscience to decouple the neuron response to the natural neuronal stimulation by bypassing the activation of the pathway, especially for olfactory transduction [20,21] or for axon guidance during the establishment of a neural map [22]. 

Biochemical insect studies of olfactory transduction began some twenty years ago and are presently an active field. The physical and... 

Fig. 4 The mechanism of insect olfactory transduction. Odorants and pheromones regulate the channel opening probability of the insect OR-Or83b receptor complex. An influx of cations depolarizes the olfactory receptor neuron (ORN), resulting in an increase in the firing rate. Depression of channel activity suppresses neural electrical activity. See Sato et al. (2008) for more details...

Lowe G et al (1989) Adenylate cyclase mediates olfactory transduction for a wide variety of odorants. Proc Natl Acad Sci USA 86 5641-5645 Lu T et al (2007) Odor coding in the maxillary palp of the malaria vector mosquito Anopheles gambiae. CurrBiol 17 1533-1544... 

Members of the bestrophin are Ca2+-activated Cl channels that have been suggested to play a pivotal role for olfactory transduction.116 According to topological models, the N- and C-terminal domains of bestrophins would be located at the intracellular side of the membrane and would be connected to four or five hydrophobic... 

Lowe G, Gold GH. 1993. Contribution of the ciliary cyclic nucleotide-gated conductance to olfactory transduction in the salamander. J Physiol 462 175-96. 

Steinbrecht, R.A. Laue, M. 1997. Topochemistry of olfactory transduction in moths. Chem. Senses, 22, in press. 

A schematic diagram of their experimental setup is shown in Fig. 11.12. The phenomenon is interesting from the viewpoint of olfactory transduction. 

Firestein, S., 1992. Electrical signals in olfactory transduction. Curr. Opin. NeurobioL, 2 444. 

Receptors of the Olfactory Transduction tom chemical to electrical signal Array of sensors... 

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