Sexual mimicry regulates the attractiveness of mated Drosophila melanogaster females.

Abstract

During mating, male Drosophila melanogaster transfer to the female's cuticle a compound (7-tricosene) that is almost absent from virgin females but is the major hydrocarbon component of the male's cuticle. During the first 3 hr after mating, the amount of7-tricosene on a female decreases sharply but remains significantly above virgin levels. By 6 hr after mating, female synthesis of 7-tricosene has increased, and females release it when they are exposed to courting males. Transfer of 7-tricosene to immature virgin females by courting males significantly decreases their attractiveness, so 7-tricosene has demonstrable antiaphrodisiac properties. Thus, mated D. melanogaster females appear to mimic males by releasing during courtship, an antiasphrodisiac pheromone that is almost absent from virgin females but is the most prominent hydrocarbon of the male cuticle.Mature virgin Drosophila melanogaster females are highly attractive (elicit high levels ofcourtship from males), but after mating, female attractiveness quickly decreases by half or more (1, 2). A complete mating, which normally lasts about 20 min, is not necessary for this initial decrease. Copulations interrupted after 3 min effect nearly the entire reduction in female attractiveness, and some reduction occurs after copulations lasting only 1 min (2). Production of female-specific courtship-stimulating compounds remains near virgin levels for about the first 3 days after mating (3), so loss of sex stimulants does not contribute to the initial decrease in female attractiveness. By 24 hr after a complete mating, females release an aversive chemical cue when they are courted (4-7). This cue probably helps maintain lower female attractiveness after the initial decrease (see ref. 8).During mating, the male-specific lipid cis-vaccenyl acetate (cVAc: cis-11-octadecen-1-yl acetate) is transferred to females (3, 9-12). Topical application ofcVAc to virgin females inhibits male courtship and mating (1,13), which suggests that cVAc could be involved in the regulation of matedfemale attractiveness (1,8,13,14). However, most of the cVAc in mated females is lost during the first 4-6 hr after mating (12,13,15). Further, the primary antiaphrodisiac of mated females is probably not the male-derived cVAc but rather a compound produced by females themselves (14). Mane et al. (1) proposed that cVAc in mated females was hydrolyzed to cis-vaccenol (cVOH) by esterase 6, another component of the male ejaculate (16). Production of cVOH could then lead to a reduction in female attractiveness beyond that due to cVAc alone (1). This hypothesis accounted for both the rapid loss of cVAc from the female and the appearance of a female-produced antiaphrodisiac. However, subsequent experiments showed that the loss of cVAc from mated females is independent of Esterase 6 transfer and that hydrolysis of cVAc to cVOH does not occur in vivo (12).Instead, cVAc lost from mated females' reproductive tracts is deposited onto the substrate, where it interacts with food odors as an aggregati...

INSEMINATION REACTION INDROSOPHILA: FOUND IN SPECIES WHOSE MALES CONTRIBUTE MATERIAL TO OOCYTES BEFORE FERTILIZATION

“…Thus, interspecific differences in frequency ofremating and sperm utilization are not tightly associated with the occurrence of the insemination reaction. Also, it has been documented that some Drosophila species use other means to impede female remating, such as the production and transfer of antiaphrodisiac pheromones in D. melanogaster (Scott, 1986).…”

Taste and pheromone perception in the fruit fly Drosophila melanogaster

“…For example, aggregation behavior and some aspects of courtship (learning) behavior are mediated by the volatile compound cisvaccenyl acetate [6][7][8][9], whereas courtship and courtship suppression are mediated to a large extent by contact pheromones, most likely long-chain hydrocarbons (HCs) [10][11][12][13]. However, unlike most mammals, which perceive most pheromones through a dedicated sensory structure, the vomeronasal organ [14], Drosophila and other insects lack a specifically dedicated organ for the sensing of pheromones.…”

Cuticular hydrocarbon analysis of an awake behaving fly using direct analysis in real-time time-of-flight mass spectrometry

“…In insects and other arthropods, these signals, many of which are cuticular hydrocarbons, can designate individual roles in social networks in addition to inf luencing courtship, colony recognition, and aggression (6,7). In Drosophila melanogaster, several studies have documented the role of hydrocarbons as aphrodisiacs (8 -11) or antiaphrodisiacs (11)(12)(13). In particular, much focus has been placed on the molecule z-11-octadecenyl acetate [cis-vaccenyl acetate (cVA)] which serves both as a mediator of mate recognition (14 -16) and an aggregation factor (8,9,14,(17)(18)(19).…”