Rickettsial symbionts in green lacewings
Rickettsia is best known as human pathogen (e.g., as causative agent of typhus or spotted fevers). However, bacteria of this genus are also one of the most common inherited symbionts of arthropods. In contrast to other typical arthropod symbionts, Rickettsia may also be found in other invertebrates, such as leeches, cnidarians, and even ciliates and amoeba.
Ricketttsia-induced phenotypes in arthropods may include sex-ratio distorting mechanisms such as male killing or parthenogenesis, but also increased fecundity.
This project aims at understanding the role of Rickettsia symbionts in green lacewings (Neuroptera: Chrysopidae). This group of holometabolous insects is best known for their predeaceous larvae, which are employed as biological control agents against crop pests such as aphids. Here, we first investigated the incidence and diversity of Rickettsia in lacewings. We found not only that many species carry Rickettsia (>50% of tested species), but also that the diversity of bacterial lineages associated with green lacewings is surprisingly high and exceeds that of any other Rickettsia host taxon.
The next steps will involve determining the fitness impacts of Rickettsia and other symbionts on green lacewings, whole genome sequencing of selected Rickettsia strains from green lacewings, and measuring the potential impact of Rickettsia on biased sex-ratios often observed in natural populations of green lacewings.
This is a collaborative project with Dr. Axel Gruppe of the Technische Universität München.
Further reading
Gerth M, Wolf R, Bleidorn C, Richter J, Sontowski R, Unrein J, Schlegel M, Gruppe A (2017) Green lacewings (Neuroptera: Chrysopidae) are commonly associated with a diversity of rickettsial endosymbionts. Zoological Letters 3: 12.
Sontowski R, Gerth M, Richter S, Gruppe A, Schlegel M, van Dam N, Bleidorn C (2018) Infection patterns and fitness effects of Rickettsia and Sodalis symbionts in the green lacewing Chrysoperla carnea. bioRxiv 327130. Link
Ricketttsia-induced phenotypes in arthropods may include sex-ratio distorting mechanisms such as male killing or parthenogenesis, but also increased fecundity.
This project aims at understanding the role of Rickettsia symbionts in green lacewings (Neuroptera: Chrysopidae). This group of holometabolous insects is best known for their predeaceous larvae, which are employed as biological control agents against crop pests such as aphids. Here, we first investigated the incidence and diversity of Rickettsia in lacewings. We found not only that many species carry Rickettsia (>50% of tested species), but also that the diversity of bacterial lineages associated with green lacewings is surprisingly high and exceeds that of any other Rickettsia host taxon.
The next steps will involve determining the fitness impacts of Rickettsia and other symbionts on green lacewings, whole genome sequencing of selected Rickettsia strains from green lacewings, and measuring the potential impact of Rickettsia on biased sex-ratios often observed in natural populations of green lacewings.
This is a collaborative project with Dr. Axel Gruppe of the Technische Universität München.
Further reading
Gerth M, Wolf R, Bleidorn C, Richter J, Sontowski R, Unrein J, Schlegel M, Gruppe A (2017) Green lacewings (Neuroptera: Chrysopidae) are commonly associated with a diversity of rickettsial endosymbionts. Zoological Letters 3: 12.
Sontowski R, Gerth M, Richter S, Gruppe A, Schlegel M, van Dam N, Bleidorn C (2018) Infection patterns and fitness effects of Rickettsia and Sodalis symbionts in the green lacewing Chrysoperla carnea. bioRxiv 327130. Link