Decoding the genetic and chemical basis of sexual attractiveness in parasitic wasps

Abstract

Attracting and securing potential mating partners is of fundamental importance for reproduction. Therefore, signaling sexual attractiveness is expected to be tightly coordinated in communication systems synchronizing senders and receivers. Chemical signaling has permeated through all taxa of life as the earliest and most widespread form of communication and is particularly prevalent in insects. However, it has been notoriously difficult to decipher how exactly information related to sexual signaling is encoded in complex chemical profiles. Similarly, our knowledge of the genetic basis of sexual signaling is very limited and usually restricted to a few case studies with comparably simple pheromonal communication mechanisms. The present study jointly addresses these two knowledge gaps by characterizing two fatty acid synthase genes, that most likely evolved by tandem gene duplication, simultaneously impacting sexual attractiveness and complex chemical surface profiles in parasitic wasps. Gene knock-down in female wasps dramatically reduces their sexual attractiveness coinciding with a drastic decrease in male courtship and copulation behavior. Concordantly, we found a striking shift of methyl-branching patterns in the female surface pheromonal compounds, which we subsequently demonstrate to be the main cause for the greatly reduced male response. Intriguingly, this suggests a potential coding mechanism for sexual attractiveness mediated by specific methyl-branching patterns in CHC profiles. So far, the genetic underpinnings of methyl-branched CHCs are not well understood despite their high potential for encoding information. Our study sheds light on how biologically relevant information can be encoded in complex chemical profiles and on the genetic basis of sexual attractiveness.

Data availability

The datasets generated or analyzed during this study are available at the figshare data repository under 10.6084/m9.figshare.20411958

The following data sets were generated

Article and author information

Author details

  1. Weizhao Sun

    Institute for Evolution and Biodiversity, University of Münster, Münster, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. Michelle Ina Lange

    Institute for Evolution and Biodiversity, University of Münster, Münster, Germany
    Competing interests
    The authors declare that no competing interests exist.
  3. Jürgen Gadau

    Institute for Evolution and Biodiversity, University of Münster, Münster, Germany
    Competing interests
    The authors declare that no competing interests exist.
  4. Jan Buellesbach

    Institute for Evolution and Biodiversity, University of Münster, Münster, Germany
    For correspondence
    buellesb@uni-muenster.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8493-692X

Funding

Deutsche Forschungsgemeinschaft (427879779)

  • Jan Buellesbach

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Rosalyn Gloag, University of Sydney, Australia

Version history

  1. Preprint posted: January 9, 2023 (view preprint)
  2. Received: January 14, 2023
  3. Accepted: July 10, 2023
  4. Accepted Manuscript published: July 11, 2023 (version 1)
  5. Version of Record published: August 17, 2023 (version 2)

Copyright

© 2023, Sun et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Weizhao Sun
  2. Michelle Ina Lange
  3. Jürgen Gadau
  4. Jan Buellesbach
(2023)
Decoding the genetic and chemical basis of sexual attractiveness in parasitic wasps
eLife 12:e86182.
https://doi.org/10.7554/eLife.86182

Share this article

https://doi.org/10.7554/eLife.86182

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