Pheromones copulating

While the unbranched 204-207 clearly originate from the acetate pool, the structure of ( )-3,7-dimethyl-2-octene-l,8-dioic acid, callosobruchusic acid 207, a female produced copulation releasing pheromone of the azuki bean weevil, Callosobruchus chinensis [374] points to a terpenoid structure. The synthetic enantiomers [375] proved to be equally effective in releasing copulation behaviour in males. 

Recently, both enantiomeric forms of callosobruchusic acid (170), a pheromone of the azuki bean weevil, Callosobruchus chinensis L., which induces the male to extrude his genital organ and to attempt copulation, were synthesized by Mori et al.178), applying Evan s alkylation method in natural product synthesis as the key step. Thus, (S)-prolinol propionamide was converted to its enolate (164) by treatment with LDA. 

There are no published reports on the neuroendocrine control of pheromone production in female P. americana, but preliminary observations (in Barth and Lester, 1973 C. Schal, unpublished data) indicated that removal of the CA completely abolished pheromone production. Pheromone production resumed in alla-tectomized females rescued with either implantation of active CA or topical application of a JH analog. Successful copulation also suppressed the production of the volatile pheromone (Wharton and Wharton, 1957), as in some other cockroaches (see below). However, Sass (1983) stated that virgin females carrying partheno-genetically produced egg cases maintained the same level of pheromone as females without egg cases. 

After copulation, the female exhibits a shift from virgin to mated behaviors. JH production is stimulated and ovulation and oviposition are accelerated in mated females (Smith et al., 1989). Mated females also become unresponsive to males, terminate pheromone production, and do not call. As in B. germanica, a two-stage process characterizes this switch (Smith and Schal, 1990b). First, insertion of the spermatophore causes an elevation in JH production and cessation of calling. However, the latter is transient, because females that mate with vasectomized males... 

Newly eclosed and immature adult females produce relatively little sex pheromone, but bioassays indicate that sex pheromone production increases as the female matures (Valentine, 1931 Happ and Wheeler, 1969) and that this increase can be stimulated by JH III (Menon, 1970, 1976). Unambiguous interpretation of these results is confounded by the fact that the sex pheromone was quantified by bioassay, generally measuring the ability of the female extract to elicit a copulation release (CR) response from the males. However, female T. molitor produces both 4-methylnonanol, which functions as a male attractant... 

What kindled our interest in this area of research was the seminal paper by Brower et al. (1965) on the courtship of the queen butterfly, Danaus gilippus, and the motion picture that these investigators made of this behavior. Their data showed clearly that the two brush-like structures, or hairpencils, that the males ordinarily kept tucked away in their abdomen are in fact everted and splayed during courtship, and brushed against the female prior to copulation. Glandular in nature, the hairpencils seemed to function as an aphrodisiac device that effected its action chemically. But the nature of the presumed pheromone and its precise communicative significance remained unknown. 

Park, S.K., Mann, K. J., Lin, H., Starostina, E., Kolski-Andreaco, A. and Pikielny, C. W. (2006). A Drosophila protein specific to pheromone-sensing gustatory hairs delays males copulation attempts. Curr. Biol., 16, 1154-1159. 

Humans are not the only creatures with a sense of smell. We can find mates using our eyes alone (though smell does play a part) but insects cannot do this. They are small in a crowded world and they find others of their own species and the opposite sex by smell. Most insects produce volatile compounds that can be picked up by a potential mate in incredibly weak concentrations. Only 1.5 mg of serricornin, the sex pheromone of the cigarette beetle, could be isolated from 65000 female beetles—so there isn t much in each beetle. Nevertheless, the slightest whiff of it causes the males to gather and attempt frenzied copulation,... 

Another reason for the relative lack of interest in mammalian pheromones lies in the fact that - apart from the use in perfumes - only one actual application of mammalian pheromones is known so far. This is not in connection with a pest but with a very useful animal, the domestic pig (5). The saliva and sweat glands of the sexually aroused boar contain two steroids with a musky smell, A16 androstenol and A16-androstenone. These are actual pheromones emitted by the male and eliciting a characteristic behaviour in the female. Sows in heat react to the scent of these compounds by assuming a characteristic copulating stance. 

Male adults of the scoliid wasp Campsoscolia ciliate are strongly attracted to the flowers of Ophrys speculum, and attempt to copulate with the flower labellum. The floral scent contains many volatiles, including trace amounts of (w-l)-hydroxy and (yj-l )-oxo acids, especially 9-hydroxydecanoic acid (R S 6 4) (25). These characteristic substances are the major components of the female sex pheromone in the scoliid wasp and induce copulatory... 

Control of mating. A new type of sex pheromone was found present in Callosobruchus chlnensls, which is not a conventional sex attractant, but rather induces the male to extrude his genital organ and to effect copulation. A female dummy bearing the pheromone mimic, elicits copulation and ejaculation by the male. 

Mating pheromones of C. chlnensis. Two sex pheromones are involved in the mating behavior of C. chlnensis a female sex attractant, and a copulation release pheromone. The former attracts the male to the female, but does not induce further responses. The latter induces the male to extrude his genital organ and to attempt copulation, and thus is named "erectin (3). Erectin is released by both the male and the female (more by the female), but only the male responds to it. 

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