A mating plug protein reduces early female remating in Drosophila melanogaster

School of Biological Sciences, University of East Anglia, Norwich, Norfolk NR4 7TJ, UK.
Journal of insect physiology (Impact Factor: 2.47). 10/2009; 56(1):107-13. DOI: 10.1016/j.jinsphys.2009.09.010
Source: PubMed


Mating plugs are formed within the female reproductive tract during mating from male ejaculate constituents or even from male genitalia themselves. Across species, mating plugs have roles in sperm storage and the prevention of female remating. In the fruitfly Drosophila melanogaster, accessory gland proteins such as the sex peptide are known to reduce female remating, however this effect can take some time to establish, hence other ejaculate components must also be involved. We hypothesised a role for the PEBII mating plug protein in the prevention of early female remating. Using RNA interference we produced PEBII knockdown males. We found that these males were significantly less able to prevent female remating in the 4h following mating. The mating plugs produced by PEBII knockdown males also showed lower levels of autofluorescence in the first 10min after the start of mating, suggesting they differed in composition to those of control males. Reduced levels of PEBII had no effect, however, on fecundity, progeny production or egg-adult viability in the first 24 after mating, suggesting there were no short-term effects of PEB II on sperm transfer, storage or use. Our results show that PEBII has a subtle but significant role in the prevention of early female remating.

21 Reads
    • "To date, only three D. melanogaster MP proteins have been identified: the PMP proteins PEBme and PEBII (Ludwig et al. 1991; Lung and Wolfner 2001; Bretman et al. 2010) and the AMP protein Acp36DE (Bertram et al. 1996). Of these, Acp36DE (Neubaum and Wolfner 1999; Bloch Qazi and Wolfner 2003; Avila and Wolfner 2009) and PEBme (this report) have an impact on female fertility. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Within the mated reproductive tracts of females of many taxa, seminal fluid proteins (SFPs) coagulate into a structure known as the mating plug (MP). MPs have diverse roles, including preventing female remating, altering female receptivity post-mating, and being necessary for mated females to successfully store sperm. The Drosophila melanogaster MP, which is maintained in the mated female for several hours post-mating, is comprised of a posterior MP (PMP) that forms quickly after mating begins and an anterior MP (AMP) that forms later. The PMP is composed of seminal proteins from the ejaculatory bulb (EB) of the male reproductive tract. To examine the role of the PMP protein PEBme in D. melanogaster reproduction, we identified an EB GAL4 driver and used it to target PEBme for RNAi knockdown. PEBme knockdown in males compromised PMP coagulation in their mates and resulted in a significant reduction in female fertility, adversely affecting post-mating uterine conformation, sperm storage, mating refractoriness, egg-laying and progeny generation. These defects resulted from the inability of females to retain the ejaculate in their reproductive tracts after mating. The uncoagulated MP impaired uncoupling by the knockdown male and, when he ultimately uncoupled, the ejaculate was pulled out of the female. Thus PEBme and MP coagulation are required for optimal fertility in D. melanogaster. Given the importance of the PMP for fertility, we identified additional MP proteins by mass spectrometry and found fertility functions for two of them. Our results highlight the importance of the MP and the proteins that comprise it in reproduction, and suggest that in Drosophila, the PMP is required to retain the ejaculate within the female reproductive tract to ensure the storage of sperm by mated females. Copyright © 2015, The Genetics Society of America.
    Genetics 06/2015; 200(4). DOI:10.1534/genetics.115.176669 · 5.96 Impact Factor
  • Source
    • "lifespan (Perry et al., 2013; Ram and Wolfner, 2007). In addition, male ejaculates often form copulatory plugs that reduce the female remating rate (Baer et al., 2001; Bretman et al., 2010; Shine et al., 2000), although they can also be important for general fertility (Dean, 2013). Such effects may often benefit males at the expense of their female mates (Oberhauser, 1989; Wolfner, 1997), resulting in the potential for antagonistic co-evolution between manipulative compounds in male ejaculates and counter-adaptations in the female reproductive tract. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Reproductive traits experience high levels of selection because of their direct ties to fitness, often resulting in rapid adaptive evolution. Much of the work in this area has focused on male reproductive traits. However, a more comprehensive understanding of female reproductive adaptations and their relationship to male characters is crucial to uncover the relative roles of sexual cooperation and conflict in driving co-evolutionary dynamics between the sexes. We focus on the physiology of a complex female reproductive adaptation in butterflies and moths: a stomach-like organ in the female reproductive tract called the bursa copulatrix that digests the male ejaculate (spermatophore). Little is known about how the bursa digests the spermatophore. We characterized bursa proteolytic capacity in relation to female state in the polyandrous butterfly Pieris rapae. We found that the virgin bursa exhibits extremely high levels of proteolytic activity. Furthermore, in virgin females, bursal proteolytic capacity increases with time since eclosion and ambient temperature, but is not sensitive to the pre-mating social environment. Post copulation, bursal proteolytic activity decreases rapidly before rebounding toward the end of a mating cycle, suggesting active female regulation of proteolysis and/or potential quenching of proteolysis by male ejaculate constituents. Using transcriptomic and proteomic approaches, we report identities for nine proteases actively transcribed by bursal tissue and/or expressed in the bursal lumen that may contribute to observed bursal proteolysis. We discuss how these dynamic physiological characteristics may function as female adaptations resulting from sexual conflict over female remating rate in this polyandrous butterfly. © 2015. Published by The Company of Biologists Ltd.
    Journal of Experimental Biology 05/2015; 218(10):1548-1555. DOI:10.1242/jeb.118323 · 2.90 Impact Factor
    • "Longer-term changes in female receptivity across a wide range of insects, however, derive from the actions of SFPs (reviewed in Gillott 2003; Arnqvist and Rowe 2005; Avila et al. 2011). In species that form mating plugs, specific mating plug proteins (e.g., PEB2 in Drosophila) can increase latency to remating in females (Bretman et al. 2010). In all cases in which SFPs influence female remating , they appear to decrease the probability or frequency of remating. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Sexual reproduction requires coordinated contributions from both sexes to proceed efficiently. However, the reproductive strategies that the sexes adopt often have the potential to give rise to sexual conflict because they can result in divergent, sex-specific costs and benefits. These conflicts can occur at many levels, from molecular to behavioral. Here, we consider sexual conflict mediated through the actions of seminal fluid proteins. These proteins provide many excellent examples in which to trace the operation of sexual conflict from molecules through to behavior. Seminal fluid proteins are made by males and provided to females during mating. As agents that can modulate egg production at several steps, as well as reproductive behavior, sperm "management," and female feeding, activity, and longevity, the actions of seminal proteins are prime targets for sexual conflict. We review these actions in the context of sexual conflict. We discuss genomic signatures in seminal protein (and related) genes that are consistent with current or previous sexual conflict. Finally, we note promising areas for future study and highlight real-world practical situations that will benefit from understanding the nature of sexual conflicts mediated by seminal proteins. Copyright © 2014 Cold Spring Harbor Laboratory Press; all rights reserved.
    Cold Spring Harbor perspectives in biology 12/2014; 7(2). DOI:10.1101/cshperspect.a017533 · 8.68 Impact Factor
Show more