Chemosensory receptors

Liberies SD, Buck LB (2006) A second class of chemosensory receptors in the olfactory epithelium. Nature 442 645-650... 

Most mammals have a second olfactory apparatus, the vomeronasal organ (VNO) or "sexual nose," which is located on the lower surface of the nasal cavity. It is a fluid-filled cavity containing chemosensory receptors through which nasal fluid is literally pumped, when the animal seeks to maximize the sensitivity of detection.908 915 The VNO is especially... 

Bruch, R. C. and Kalinoski, D. L., Interaction of GTP-binding regulatory proteins with chemosensory receptors, J. Biol. Chem., 262, 2401, 1987. 

Peckol E. L., Troemel E. R. and Bargmann C. I. (2001) Sensory experience and sensory activity regulate chemosensory receptor gene expression in Caenorhabditis elegans. PNAS 98, 11032-11038. 

Troemel E. R., Chou J. H., Dwyer N. D., Colbert H. A. and Bargmann C. I. (1995). Divergent seven transmembrane receptors are candidate chemosensory receptors in C. elegans. Cell 83, 207-218. 

Zimmer-Faust R. K., Gleeson R. A. and Carr W. E. S (1988) The behavioral response of spiny lobsters to ATP evidence for mediation by P2-like chemosensory receptors Biol. Bull. 175, 167-174. 

The sensitivity and selectivity of olfaction and contact chemosensation are due (1) in the brain, to the existence of a neuronal network of neurons tuned to a specific chemical stimulus, and (2) in the periphery, to the existence of olfactory/ chemosensory receptor neurons housed in sensory microorgans called sensilla. The sensilla can best be viewed as simple cuticular porous extrusions that increase the surface that captures airborne odorants or chemicals dissolved in water droplets. They contain the receptive olfactory or chemosensory structures (Schneider, 1969). The olfactory sensilla are most numerous on the antennae and mediate the reception of sex pheromones and plant volatiles, as well as other odorants. Low volatility pheromones may also be detected by contact chemoreceptors on... 

An alternative to genetics has been heterologous expression of ORs, either in vivo (Zhao et al., 1998 Araneda et al., 2000) or in tissue culture cells (Krautwurst et al., 1998 Touhara et al., 1999), and the use of functional imaging of isolated OSNs to determine their response profiles (Malnic et al., 1999 Leinders-Zufall et al., 2000). These studies of vertebrate chemosensory receptors have led to the... 

Mombaerts P. (1999) Seven-transmembrane proteins as odorant and chemosensory receptors. Science 286, 707-711. 

Figure 3. Location of some oral chemosensory receptor systems. Taste buds (schematic upper right) are found on specialized papillae on the tongue and scattered on the palate and posterior oral structures. Free nerve endings are found...

There are many other recent studies wherein fluorinated amino acids have been incorporated into bacterial protein, and into mammalian protein expressed in bacteria cells, for, 9F-NMR experiments. For example, 5-FTrp and 3-FPhe were incorporated into the d-galactose chemosensory receptor of E. coli. Site-directed mutagenesis was use to assign 19F-signals186. 

Ffe. 5.14 Dendrogram of the protein sequences of chemosensory receptors and G-protein-coupled receptors, GPCRs. Although rhodopsin and serotonin receptors are clearly related between humans and Drosophila, the Drosophila olfactory receptors are unrelated to the olfactory receptors in vertebrates. (Reproduced from ref. 83 with permission of the authors and Nature.)... 

Extraordinary Diversity of Chemosensory Receptor Gene Repertoires Among Vertebrates... 

Table 1 Sizes of chemosensory receptor gene repertoires in vertebrates...

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