Schärer Group
Evolutionary Biology
Zoological Institute
University of Basel
Vesalgasse 1
CH-4051 Basel
Switzerland

Jeanne Brülhart

email: jeanne.bruelhart-at-stud.unibas.ch

I am a MSc student in the Schärer group. I am mainly interested in the molecular processes underlying sexual selection and sexual conflict.

Current research

Simultaneous hermaphrodites are confronted with conflict over the mating role of individuals. Usually, individuals are more eager to donate than to receive sperm during mating, which can lead to numerous antagonistic adaptations and counter-adaptations over the course of evolution. In many reciprocally mating species of the genus Macrostomum, the so-called suck-behavior has been proposed to have evolved as way to get rid of unwanted ejaculate that individuals have to accept in exchange of being allowed to transmit their own sperm. Two seminal fluid proteins (SFPs), Mlig-Pro31 and Mlig-Pro32, have recently been identified by Patlar et al. (2020) and proposed as a counter-adaptation to the suck behavior. After being transferred with the ejaculate during a mating event, these two proteins decrease the suck propensity of the mating partner, which allows the sperm donor to regain control over the fate of the transferred ejaculate.
Since many other Macrostomum species also show the suck behavior, I am interested in discovering whether they exhibit the same counter-adaptation. M. janickei is the closest known relative of M. lignano. It mates reciprocally and also shows the suck behavior, which makes it an ideal candidate to investigate this question. Using RNA interferance (RNAi) and in situ hybridization (ISH), I am trying to find if I can identify orthologs of Mlig-pro31 and Mlig-pro32 genes in M. janickei and whether they have the same function as in M. lignano.

Figure 1. ISH for one of the ortholog candidate of Mlig-pro32 in Macrostomum janickei.
The coloration indicates the organs where the protein of interest is expressed. Here, only the prostate glands are highlighted.
This is in accordance with what we would expect for SFPs, supporting the hypothesis that this candidate could be a Mlig-pro32 ortholog.

Former research

For my BSc thesis, I looked at adaptation of life-history traits to latitudinal clines in Drosophila melanogaster. I used populations from an experimental evolution study to look at the effect of allelic competition and evolution temperature on different life-history traits.

Publications

none yet