Acquisition, persistence, and loss of reproductive symbionts


Heritable bacterial symbionts are an important component of arthropod ecology and evolution. Many of these symbionts are maternally transmitted, following an ovarial transmission route. Maternally transmitted symbionts can spread rapidly within arthropod populations by inducing various reproductive phenotypes. These phenotypes include: cytoplasmic incompatibility, parthenogenesis, and sex allocation distortion.
We use a diversity of entomological systems to dissect the traits that shape the acquisition, persistence, and loss of (endo)symbiotic infection in arthropods. Our model systems include rove beetles, ants, leaf-mining flies, and spider mites (we love arthropods). Across these divergent systems, we unravel the mechanisms and efficiency of maternal transmission. We study the mechanistic basis of symbiont-mediated phenotypes from the perspective of host and symbiont. Our work also contributes to the development of effective and stable CI-based pest management.

                                                                                        

 

Hybrid dysfunction

Incompatible matings can result in dysfunctional hybrid offspring that suffer from sterility and inviability. Hybrid dysfunction is a strong isolating barrier that drives speciation and maintains species barriers and its underpinning genetic processes have captivated evolutionary biologists since the early 20th century. The complex Tetranychus genus consists of cryptic species group that are typified by widespread nuclear and mito-nuclear incompatibilities that cause multiple hybrid defects. We focus on characterizing the molecular basis of hybrid dysfunction and identifying the causal incompatibility alleles.

 

Herbivory

Herbivory, or feeding on non-decayed plant material, has only evolved in approximately one third of all animal species. Plant feeding imposes major nutritional challenges to animals. Plant tissues are typically nutritionally imbalanced and contain complex phytochemicals, recalcitrant to enzymatic digestion. In addition, in response to feeding, plants have developed many chemical defense mechanisms to protect themselves. To counter these chemical defences, arthropods in turn develop an arsenal of enzymatic mechanisms, of which detoxification and transportartion are best studied. Cyanogenesis is a common plant defence mechanism that releases toxic cyanide upon herbivore feeding. Several arthropod lineages have acquired a cyanide detoxification gene by horizontal gene transfer from bacteria. We are currently building on the established functionality to fully couple varying levels of resistance to plant-produced cyanide to arthropod species and genotype. Here, we combine field entomology with population and molecular biology.

We study granivorous Messor ants, leaf-mining agromyzid flies, and cell content-feeding spider mites.