The Verhulst-group is embedded in the Laboratory of Entomology, Plant Sciences Group, Wageningen University. Our work is in the field of evolutionary developmental biology with a focus on the evolution of sex determination and differentiation in insects. In addition, the PI collaborates on biocontrol focused projects.
Our drive
The appearance of both sexes from the same species is often highly diverse; sometimes it is even hard to tell whether a male and a female belong to the same species at all! Insects are one notable class of organisms that showcase extreme differences between sexes, called sexual dimorphism. In addition to their diverse appearances, insects also have an astounding diversity in their molecular pathway that determines the sex during early development, the sex determination cascade. This variation is unexpected as the net result is always the same: male or female development.
All insects studied have the same gene, called doublesex, that regulates their sexual development and morphology. Doublesex is a transcription factor and responsible for regulating all the different sexually dimorphic traits that can be observed in nature. However, we still have limited understanding of the molecular mechanisms that underlie the huge dimorphic differences that we can see in insects. Do genes come and go, or do all insects have more or less the same set of genes and is there a difference in the regulation of these genes?
Over 40 years ago, King and Wilson reported that enormous differences in phenotype and behaviour are often not due to differences in protein sequence. They discovered that the evolution of gene regulation is a key player in adaptation and speciation. We have now gained first insights into this regulatory evolution and its players, but we are a long way from having a comprehensive understanding of the relation between transcription factor protein evolution and the continuously changing genetic architecture of their binding sites that regulate target gene expression.
In our research we aim to get a deeper understanding of the way evolution shapes molecular pathways that result in a bewildering biodiversity. Our main research interests are:
1) unraveling the evolution ofsex determination cascades, an important developmental pathway; to understand the enormous diversity in sex determining mechanisms throughout the animal kingdom.
2) the interaction ofdoublesex with its target genes, the highly conserved transcription factor at the bottom of the cascade, to understand how this ultimately result in rapid evolution of sexual dimorphic traits.
3) understanding challenges in polyploid evolution, by comparing a decade-old polyploid Nasonia vitripennis line with newly created polyploid lines by clever use of sex determination mutants.
In addition, we are involved in the fundamentals of using parasitoid wasps in biological control and integrated pest management.
20 January 2022 Four papers were accepted in the last few weeks, see Publications!
10 Jan 2022 Jade van Doorn starts her MSc thesis in our lab
12 November 2021 Julien presents his selected talk at the Dutch Chromatin Meeting 2021 on maternal silencing in N. vitripennis sex det.
25 October 2021 Keita Yamaguchi starts his Capita Selecta project in our lab
5 October 2021 Yidong Wang succesfully defended his thesis entitled: "Controlling sex - evolution of sex determination, sexual differentiation and endosymbiont-induced asexual reproduction in three parasitoid wasps" at WUR
14 & 23 September 2021 Karthick Gayendiran and Gabriel Charvalakis succesfully defend their MSc thesis
9 September 2021 Aidan will present his work on the Doublesex regulation of pheromone communication and odour-guided behaviour in Nasonia wasps at the International Society of Chemical Ecology 2021 conference
9 August 2021 Our review on the development and evolution of a sexually-dimorphic antennal lobe has been submitted to Entomologia Experimentalis et Applicata
3 August 2021 Our paper describing the Masc gene in Ephestia kuehniella is published in PLoS Genetics