Transfer and fate of male ejaculate in female Queensland fruit flies

Abstract

Insect seminal fluid commonly comprises a complex cocktail of proteins and other biochemical components that migrate away from the female reproductive tract to sites elsewhere in the female body and elicit changes in female reproductive behaviour. The transfer of male seminal fluid molecules to reproductive and somatic tissues of the female Queensland fruit fly ('Q-fly') Bactrocera tryoni is examined and some putative target sites identified. Male Q-flies are fed a diet containing radiolabelled ( 35 S) amino acids, which are incorporated into male accessory gland products. Radioactivity diminishes within the accessory glands and increases in all assessed parts of the female body during copulation, indicating the transfer of these products into the female soma via the reproductive tract. There are significant changes in the absolute and proportional radioactivity profiles among female tissues over the next 22 h, with substantial reductions in the thorax and increases in the head. This is consistent with accumulation of behaviour-modifying male products at binding sites in the female head. Parallels can be drawn between the data in the present study and seminal fluid distribution profiles and receptor binding documented in other insects.

Post‐teneral nutrition as an influence on reproductive development, sexual performance and longevity of Queensland fruit flies

“…On the other hand, Radhakrishnan and Taylor (2007) provide strong evidence supporting the involvement of accessory gland fluids transferred with the ejaculate as mediators of sexual inhibition (see also Radhakrishnan et al. 2008, 2009a).…”

“…2008, 2009a). Materials from the male’s ejaculate pass through the female’s reproductive tract and disperse through her body while the pair mates (Radhakrishnan et al. 2008).…”

“…After mating, male accessory glands are greatly diminished in size and recover their original size gradually over the following day (Radhakrishnan and Taylor 2008). These changes in accessory gland dimensions presumably reflect volume of contents, as fluids are transferred to females during copulation and then replenished in time for the next mating opportunity (Radhakrishnan et al. 2008).…”

Who’s Zooming Who? Seminal Fluids and Cryptic Female Choice in Diptera

“…In Diptera, some Sfps are found in female hemolymph or in tissues outside of the reproductive tract (e.g., Monsma et al 1990;Pitnick et al 1997;Lung and Wolfner 1999;Ravi Ram et al 2005;Pilpel et al 2008) or are suggested to enter the hemolymph based on radiotracer studies (e.g., Markow and Ankney 1984;Radhakrishnan et al 2008) or on the occurrence of traumatic insemination (e.g., Kamimura 2007). In D. melanogaster, introduction of SP into the hemolymph has been shown to be sufficient to induce changes in egg production and receptivity (Chen et al 1988;Aigaki et al 1991) and two other Sfps with identified effects on female physiology or behavior (ovulin: Herndon and Wolfner 1995;Heifetz et al 2005; Acp62F: Mueller et al 2008) have been found in the hemolymph of mated female flies.…”

Trapping and the Detection, Control, and Regulation of Tephritid Fruit Flies

“…Mating-induced sexual refraction has been found in C. capitata (Chapman et al 1998;Miyatake et al 1999;Mossinson and Yuval 2003;Kraaijeveld and Chapman 2004), the olive fruit fly, Bactrocera oleae (Rossi), (Cavalloro and Delrio 1970;Tsiropoulos and Tzanakakis 1970), various Anastrepha species B. tryoni (Barton Browne 1957;Harmer et al 2006;Pérez-Staples et al 2008;Radhakrishnan et al 2008) but not in R. pomonella (Opp and Prokopy 2000). Searching behavior is modified after mating in C. capitata, since virgin females are preferentially attracted to the male pheromone over host fruit odors, while the opposite characterizes mated females .…”