Investigating the role of signalling and the cytoskeleton during Vaccinia virus egress

About the project

About the Project A 2027 Crick PhD project with Michael Way. Project background and description Viruses are obligate intracellular parasites that critically depend on their hosts to generate new progeny. Investigating how viruses use the different cellular machineries and processes of their hosts during replication, assembly and spread offers a unique opportunity to obtain mechanistic insights into the regulation and function of diverse cellular processes. It can also provide important insights into the underlying cause of disease and helps identify potential targets for therapeutic intervention. To this end, our laboratory (website - https://michaelway0.wixsite.com/waylab ) uses Vaccinia virus as a model system, combining quantitative imaging and biochemical approaches to study a variety of cellular processes, including regulation and function of RhoGTPases, host pathogen interactions, actin and microtubule-based transport, as well as septins. Vaccinia virus is the prototypical member of the poxvirus family, which includes the causative agents of smallpox and mpox. Like all poxviruses, Vaccinia undergoes a complex replication and assembly process within peri-nuclear viral factories in the cytoplasm of infected cells [1]. Following assembly, both intracellular mature (IMV) and intracellular enveloped (IEV) virions recruit kinesin-1 to undergo microtubule-based motility from their site of assembly to the plasma membrane [2]. We have a good understanding of how IEV recruit kinesin-1, but the molecular basis for motor recruitment to IMV still remains unknown. We also lack an understanding of how virions fuse with the plasma membrane and how the cytoskeleton and associated signalling pathways regulate viral exocytosis. Immediately after virion fusion with the plasma membrane, but prior to the induction of actin polymerization, vaccinia recruits septins and clathrin [3, 4]. Septins act as a restriction factor that suppresses viral release from the cell, while clathrin enhances viral spread by promoting actin assembly. The molecular basis for septin recruitment beneath extracellular virions on the plasma membrane remains unknown. In addition, the roles of other signaling pathways, including Rho /Arf GTPase and lipid signalling, in viral exocytosis and virus induced actin polymerization remain to be investigated. In summary the project aims to address the outstanding questions outlined above, using a combination of biochemical, structural and cellular approaches. These will include advanced live cell imaging and in vitro motility assays to investigate the role of signalling and understand the role of molecular motors (kinesins and myosins), as well as microtubules, actin and septins in the assembly and egress of vaccinia virus. Candidate background The precise project will be decided based on the candidate’s background and interests in consultation with the supervisor during the interview. Applicants should have a background in cell biology, biochemistry or biophysics and be interested in using advanced imaging and in vitro approaches to investigate signalling and cytoskeletal regulation. The Way lab uses a multidisciplinary approach so students will receive training in a wide variety of techniques. However, I am particularly interested in receiving applications from candidates with experience in biochemistry, live cell imaging and/or image analysis. Lab-specific question What do you consider to be an important unanswered question in the Way lab, and how would you approach addressing it?

Research areas