MRC DiMeN Doctoral Training Partnership: Identification of cellular receptors for bunyaviruses, a group of emerging haemorrhagic fever viruses

Many viruses infect cells by hijacking cellular trafficking pathways, beginning by using their external spikes to bind specific receptor molecules on the cell surface. The receptor/virus complex then gets internalised into the cell, where it enters the cellular endocytic pathway, with the virus mimicking a useful cargo. The objective of this PhD project is to identify and characterise the cell surface receptors used by a group of human pathogenic viruses called the bunyaviruses. Knowing the identify of viral receptors can pave the way for understanding much about the molecular basis for virus pathogenesis, tissue tropism, host range/switching, virus emergence as well as providing targets for antiviral therapies that may block the virus/receptor interaction. 

Bunyaviruses are a large group of around 500 insect-borne viruses, with notable examples Rift Valley fever virus (RVFV), Crimean-Congo haemorrhagic fever virus (CCHFV) and Oropouche virus (OROV), all of which are associated with devastating, often fatal, untreatable human disease. Several bunyaviruses are recognised by the WHO as emerging viruses with pandemic potential and thus are classed as so-called ‘priority pathogens’ that require urgent research and development. The cellular receptor for human infection by RVFV, CCHFV and OROV is known to be LRP1, a cellular protein responsible for the import of molecules known as low density lipoproteins, which represent an important source of components used for cellular metabolism. However, in the case of CCHFV, recent work suggests the viral spikes do not directly bind LRP1, but instead, the virus and LRP1 depends on a host factor called apolipoprotein-E (ApoE) that binds the viral spikes, forming a bridge to LRP1. This project aims to identify the receptors for other bunyaviruses and also determine whether they also use host lipoproteins to bridge the spike-receptor interaction. We will achieve this by exploiting CRISPR gene knock-out technologies to identify both essential and contributing host proteins required for the entry of a broad panel of bunyaviruses into both mammalian and insect cells. Validation of potential receptors will be achieved by visualising viruses in the process of infecting both permissive as well as knock-out cell lines. We further aim to determine the molecular details of spike-receptor-lipoprotein interaction through direct visualization of purified virions using cryo-electron microscopy (cryo-EM). Techniques will include CRISPR-Cas9 gene editing, virus manipulation using reverse genetics, virus purification, cutting edge confocal and cryo-EM alongside genome-wide screening strategies. Candidates will acquire highly transferable skills preparing students for a potential research career in virology, or in the wider field of molecular, cellular and structural biology. 

Supervisor webpages:  

Primary supervisor, Dr John N. Barr: 

https://biologicalsciences.leeds.ac.uk/molecular-and-cellular-biology/staff/22/dr-john-n-barr 

Secondary supervisor, Dr Martin Stacey: 

https://biologicalsciences.leeds.ac.uk/molecular-and-cellular-biology/staff/138/dr-martin-stacey 

Benefits of being in the DiMeN DTP: 

This project is part of the Discovery Medicine North Doctoral Training Partnership (DiMeN DTP), a diverse community of PhD students across the North of England researching the major health problems facing the world today. Our partner institutions (Universities of Leeds, Liverpool, Newcastle, York and Sheffield) are internationally recognised as centres of research excellence and can offer you access to state-of-the-art facilities to deliver high impact research. 

We are very proud of our student-centred ethos and committed to supporting you throughout your PhD. As part of the DTP, we offer bespoke training in key skills sought after in early career researchers, as well as opportunities to broaden your career horizons in a range of non-academic sectors. 

Being funded by the MRC means you can access additional funding for research placements, training opportunities or internships in science policy, science communication and beyond. Further information on the programme and how to apply can be found on our website: 

https://www.dimen.org.uk/