Program:
15.00-15.15: coffee & cake in the foyer
15.15-16.15: scientific talk in Auditorium I

Speaker: Marta Bally, Associate Professor of Virology, Umeå University

Abstract:
The initial recruitment of a virus particle to the cell surface requires diffusion of the virus particle through the glycocalyx, the sugar coat covering cells, to reach the cell membrane where it may further diffuse laterally in search of a suitable point of entry. This complex and dynamic process is mediated by a multitude of well-timed biomolecular interactions which act in concert to optimize entry. In this context, the affinity of the interaction between individual ligands and receptor, as well as the number of bonds established between the virus particle and the cell surface, is likely key in fine-tuning the dynamic characteristics of the virus at the cell surface.  

In our work, we study the molecular mechanisms modulating virus attachment, detachment and diffusion at the cell surface. We primarily focus on viruses interacting with heparan sulfate, a chemically heterogeneous polysaccharide abundantly found on most cells. Our experimental approach is based on probing interactions between individual virus particles and the cell surface using both cell-surface mimics of controlled biomolecular composition, and live cell microscopy. Single particle tracking and total internal reflection fluorescence microscopy are used to study the interaction kinetics and diffusion of individual viruses. Complementary atomic force microscopy-based single molecule force spectroscopy contributes to studying individual ligand-receptor interactions involved in the process.

Taken together, our research contributes to a better understanding of the mechanisms regulating the interaction between a virus and the surface of its host. Such insights will without doubt facilitate the design of more efficient antiviral drugs or vaccines.

Figure: The initial recuitment of a virus at the cell surface is a highly dynamic process which may require diffusion of the virus through the glycocalyx and at the cell surface. The biomolecular interactions involved need to be tighly regulated to ensure efficient virus transport and entry.