Plant-parasitic nematodes are economically important crop pathogens that cause billions of dollars of crop losses to agriculture throughout the world. They are good examples of biotrophic pathogens that have evolved sophisticated interactions with a host in order to avoid the plant’s defences and live successfully inside the roots. Endoparasitic nematodes invade host roots and stimulate root vascular tissue to undergo cell division and re-differentiate into unique and metabolically active “feeding sites” from which they feed for a number of weeks (Jones et al., 2013).
At the same time, plants are also host to a range of other diverse biotrophic organisms. Some of these, like the nematodes, are damaging, whilst others are mutualists (e.g. arbuscular mycorrhizal fungi). Different symbionts often colonise their hosts simultaneously. This means that importantly, all symbionts must compete for the finite amount of host resources on offer to fuel their development and reproduction. Many studies describe the movement of resources between host and symbionts yet the mechanisms that underpin resource allocation and how they change upon symbiosis with multiple organisms remain unknown.
Our recent experiments indicate that damaging plant-parasitic nematodes acquire fewer resources from hosts that are simultaneously nourishing beneficial arbuscular mycorrhizal fungi, i.e. the same amount of food has to be shared around (Bell et al., 2022). We have preliminary evidence to suggest that nematodes detect and respond to this change in available nutrients in order to maximise their acquisition of sustenance by tailoring the expression of genes involved in resource acquisition and uptake.
This project will develop that preliminary work and as its starting point investigate the transcriptional response of root-knot nematodes when they are exposed to varying levels of nutrition from their host plant. This would involve co-colonisation with other symbionts, and also widen to look at host plants on which the nematodes are more or less successful. These experiments will provide a picture of how nematode gene expression changes with nutrient availability. The initial focus would be on genes involved in nutrient uptake and assimilation and the student would determine how the nematodes have evolved to feed optimally from their hosts in a range of conditions. Further experiments will determine the role of selected genes in nematode nutrient acquisition and explore how they are regulated, for example SWEET genes. The student will gain experience of the culture and analysis of plant parasitic nematodes and their host plants. The project will provide training in a range of molecular and bioinformatic techniques, including analysis of RNA sequencing data, gene cloning, RNA interference and quantitative PCR.
Eligibility:
You should hold a first degree equivalent to at least a UK upper-second class honours degree or a MSc degree in a relevant subject.
Applicants whose first language is not English must provide evidence that their English language is sufficient to meet the specific demands of their study. The Faculty of Biological Sciences minimum requirements in IELTS and TOEFL tests are:
- British Council IELTS - score of 6.0 overall, with no element less than 5.5
- TOEFL iBT - overall score of 87 with the listening and reading element no less than 20, writing element no less than 21 and the speaking element no less than 22.
How to apply:
To apply for this project applicants should complete an online application form and attach the following documentation to support their application.
- a full academic CV
- degree certificate and transcripts of marks
- Evidence that you meet the University's minimum English language requirements (if applicable).
To help us identify that you are applying for this studentship please ensure you provide the following information on your application form;
- Select PhD in Biological Sciences as your programme of study
- When asked for source of funding please make it clear that you are applying for a "Gosden PhD Scholarship"
- Give the full project title and name the supervisors listed in this advert.
If you have any further queries regarding this opportunity, please contact [Email Address Removed]
Continue with Facebook
