PhD: viral manipulation of caterpillar behaviour in a multidimensional context

Many parasites, including viruses, manipulate the behaviour of host organisms to increase their own transmission, linking to the concept of the ‘extended phenotype’. Fascinating examples include behavioural manipulation of caterpillars by baculoviruses, with infected caterpillars expressing hyperactivity as well as climbing to elevated positions on plants just prior to death. These behavioural alterations have a crucial evolutionary benefit to the virus, enhancing its transmission. Until now, parasitic manipulation of host behaviour has been investigated as a bidirectional interaction between the manipulative parasite and the host.

While the possible influence of the host or parasite microbiome on host behavioural manipulation is starting to be recognized, the influence of the host’s resident virome has so far been ignored. The past decades, evidence has accumulated that insects harbour a wide range of covert virus infections that do not cause any signs of disease. In this project, you will study manipulative parasite-host interactions in a multidimensional context, by investigating how covert virus infections modulate crosstalk between manipulative baculoviruses and their caterpillar host.

You will start with analysing the phenotype of baculovirus-induced behavioural manipulation across several closely and more distantly related baculoviruses and lepidopteran hosts, and determine the impact of the insect’s virome on the manipulation. Next, you will investigate in detail the molecular mechanisms underlying the manipulation, especially focusing on changes induced in the lepidopteran central nervous system (CNS). You will specifically perform an in-depth analysis of viral CNS invasion and determine localisation of baculoviruses as well as covert virus infections.

Furthermore, you will validate putative mechanisms by functional analyses of candidate genes and proteins, using a range of techniques including RNAi and CRISPR/Cas9 technology. This research will aid in identifying how virus-induced manipulation has evolved across lepidopterans and identify commonalities and differences in underlying mechanisms, and will also reveal how the behavioural outcome of manipulation is dependent on the context of resident viruses present in the host.

This PhD project is part of a larger Vici project, funded by the Dutch Research Council (NWO). As such, you will closely collaborate with another PhD student and a postdoc in this project, working on related questions.

As a PhD candidate you will contribute to fundamental science in the context of insect virology. In addition, you will participate in cursory teaching of the chair group. You will be embedded in the Laboratory of Virology. In addition, you will collaborate with (inter)national colleagues from both in- and outside Wageningen University & Research.

Your duties and responsibilities include:

• Designing and executing experiments with insects and viruses, measuring behavioural manipulation;
• Investigating the molecular mechanisms underlying behavioural manipulation using dissections, transcriptome, proteome and small RNA profiling;
• Studying virus invasion of the lepidopteran central nervous system, using GFP-labelled viruses, hybridisation techniques, antibody labelling and microscopy;
• Teaching in courses and supervise BSc and MSc students;
• Writing and presenting research at/in internationally renowned conferences/journals.

You will work here
You will work with in the Insect Virology group, as part of the NWO Vici project ‘Invisible influencers: How hidden virus infections shape insect life’ led by Dr. Vera Ros. The project is aimed at disentangling how the insect’s virome (i.e. the assemblage of viruses) impacts insect immune responses, fitness and behaviour, and thereby influences interactions with and effects of incoming virus infections.

The Insect Virology group is part of the chair group Laboratory of Virology, and research in Insect Virology focuses on multiple aspects of insect-virus interactions including mechanisms behind viral manipulation of insect behaviour, virus discovery, covert virus infections (i.e. infections without clear symptoms) in insects and the use of viruses for biological control of insect pests. You will be supervised by Dr. Vera Ros (WUR Laboratory of Virology) and Prof. Monique van Oers (chair of the WUR Laboratory of Virology). In addition, you will also be embedded in the PE&RC graduate school (Home | PE&RC), which will allow you to follow a wide variety of training courses and will provide support during your academic journey.

The Laboratory of Virology is part of the Plant Sciences Group of Wageningen University. It is located at the Wageningen Campus in the Radix building. We provide virology teaching at Wageningen University within BSc and MSc programs across various disciplines. The Virology chair group comprises around 35 members, including research/teaching staff, technicians, PhD candidates, postdocs and visiting researchers. Each year, an average of 25 BSc and MSc students undertake their final-year thesis research within Virology. The Virology group conducts fundamental research into plant viruses, insect viruses and arboviruses. Where possible, the knowledge generated is translated into applications aimed at improving food production and human and animal health.