Reconstitution of influenza virus assembly in asymmetric model membrane systems


Cellular membranes are complex biological entities which perform a wide range of functions. The lateral organization of lipids and receptors in the plasma membrane (PM), for example, is involved in several biological processes such as cell-cell communication or viral infections. The mechanism by which the Influenza virus (IV) infects a cell and, eventually, spreads to other cells is paradigmatic in this context. It is known, in fact, that assembly and budding of progeny influenza virions is an intricate process that occurs through specialized lipid-protein domains of the PM named “rafts”. Unfortunately, the detailed molecular mechanisms behind this process remain unclear. In order to dissect the complex interactions between viral components and the lipids and membrane proteins of the host cell, we will use novel physical models of the PM, i.e. asymmetric model membranes. This represents an important step forward in the field of membrane biophysics since, until recently, investigation of lipid-protein interaction has been carried almost exclusively on symmetric simple models of cellular membranes. These model bilayers did not take into account the important compositional asymmetry between inner and outer leaflets of PM.

Our general goal is to clarify the molecular interactions governing the budding and exit of IV from infected cells, by reconstituting the key viral components in the above-mentioned reliable and controlled membrane models and characterizing them with a sophisticated combination of Atomic Force Microscopy and advanced fluorescence microscopy techniques. Firstly, we will focus on the role of the viral matrix protein M1 in orchestrating the spatial assembly of IV components into a new virion budding from the host PM. Furthermore, we will investigate the relationship between the raft domains in the PM and IV infectious cycle. The interaction between IV components and PM raft domains is, in fact, not well understood.

The knowledge deriving from the experiments described above will be of great value for understanding the molecular mechanisms of IV exit from host cells and, ultimately, developing innovative methods to prevent the spreading of the viral infection.

Cellular membranes are complex biological entities which perform a wide range of functions. The lateral organization of lipids and receptors in the plasma membrane (PM), for example, is involved in several biological processes such as cell-cell communication or viral infections. The mechanism by which the Influenza virus (IV) infects a cell and, eventually, spreads to other cells is paradigmatic in this context. It is known, in fact, that assembly and budding of progeny influenza virions is an intricate process that occurs through specialized lipid-protein domains of the PM named “rafts”. Unfortunately, the detailed molecular mechanisms behind this process remain unclear. In order to dissect the complex interactions between viral components and the lipids and membrane proteins of the host cell, we will use novel physical models of the PM, i.e. asymmetric model membranes. This represents an important step forward in the field of membrane biophysics since, until recently, investigation of lipid-protein interaction has been carried almost exclusively on symmetric simple models of cellular membranes. These model bilayers did not take into account the important compositional asymmetry between inner and outer leaflets of PM.

Our general goal is to clarify the molecular interactions governing the budding and exit of IV from infected cells, by reconstituting the key viral components in the above-mentioned reliable and controlled membrane models and characterizing them with a sophisticated combination of Atomic Force Microscopy and advanced fluorescence microscopy techniques. Firstly, we will focus on the role of the viral matrix protein M1 in orchestrating the spatial assembly of IV components into a new virion budding from the host PM. Furthermore, we will investigate the relationship between the raft domains in the PM and IV infectious cycle. The interaction between IV components and PM raft domains is, in fact, not well understood.

The knowledge deriving from the experiments described above will be of great value for understanding the molecular mechanisms of IV exit from host cells and, ultimately, developing innovative methods to prevent the spreading of the viral infection.

Principal investigators
Chiantia, Salvatore Dr. rer. nat. (Details) (Molecular Biophysics)

Duration of project
Start date: 06/2014
End date: 05/2017

Last updated on 2022-07-09 at 13:06