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(M38) BIOCHEMICAL ASPECTS OF PHEROMONE COMMUNICATION IN THE HOUSE MOUSE. Novotny, Milos1, 1 Institute for Pheromone Research, Bloomington, IN ABSTRACT- The house mouse is notable among the mammals with an exceptionally well-developed system of chemical communication. During the years of investigating its chemical communication system, we have identified several chemosignals (putative pheromones) in Mus domesticus: male-originated 3,4-dehydro-exo-brevicomin and 2-sec-butyl-4,5-dihydrothiazole, KEY WORDS: olfaction, pheromones, Mus domesticus, urinary proteins |
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-farnesenes and 6-hydroxy-6-methyl-3-heptanone; and female-originated 2,5-dimethylpyrazine. Their pronounced effects on physiology and behavior were subsequently demonstrated with the use of synthetic pheromone analogs (intermale aggression, dominance signaling, and the primer effects such as puberty acceleration and delay). Most recently, our attention has been directed to the role of these volatile ligands in a seemingly complex process of pheromone release and perception at the target olfactory tissues. Different protein types play a significant role in the overall process: (a) major urinary proteins (MUPs); (b) receptor proteins of the neuronal membranes; and (c) soluble proteins that may assist in the so-called "perireceptor events". The mouse MUPs, which are excreted in very high levels in the urine of both laboratory and wild mice, are now believed to be primarily responsible for modulating a release of volatile pheromones. They represent a complex conglomerate of different isoforms whose structures may vary in dependence to genetic background and gender. Using several different recombinant MUPs and synthetic pheromones, we have recently performed detailed binding studies using X-ray crystallography, NMR spectrometry, and microcalorimetric measurements. Different binding affinities were noted for MUPs expressed in different tissues. Along different lines, we have investigated several proteins isolated from the mucus of main olfactory tissue and the vomeronasal organ. While several "pheromone-binding proteins" were found to be synonymous, or at least similar, to the previously investigated odorant-binding proteins, several unique glycoproteins have also been noted. Detailed structural analyses indicated that there is a sexually dimorphic expression and glycosylation for some of these biomolecules. However, their participation in perireceptor events remains unclear.