Characterization of the interaction between the methylosome and the human respiratory syncytial virus nucleocapsid

Abstract

The Human respiratory syncytial virus (HRSV) is one of the most important pathogens of the respiratory tract, causing respiratory illness particularly in newborns, babies, children and immunocompromised patients. Until the present there is no vaccine approved or antiviral effective against the HRSV. The genome of HRSV encodes eleven proteins, being fundamental to understand its relationship with the host, to characterize the interactions between those proteins and cellular components. In previous work of the laboratory viral nucleoprotein (N), phosphoprotein (P) and matrix (M) interactions with cellular proteins were analyzed both by the individual expression of these viral proteins transfecting plasmid vectors, as well as in the context of infection, in HEK-293T cells. It was found that N interacts with cellular proteins Hsp70, PRMT5 and WDR77; P interacts with Hsp70 and Tropomyosin; and M with Nucleophosmin and Tropomyosin. These interactions are being explored in greater detail in the lab, and in this project we aim to understand the interaction of proteins WDR77 and PRMT5, constituting the methylosome, with the N protein. N associates with the viral RNA forming the basic structure of the helical nucleocapsid of HRSV. N has arginine residues exposed on the surface that are potential targets of methylation by PRMT5. This modification could be modulating the interaction between N and the viral RNA, enabling access of viral RNA polymerase during the processes of transcription and replication. We propose to confirm these interactions with new approaches and search, in various stages of viral replication, for methylation or other transient post-translational modifications in N protein. In addition, we propose to carry functional tests, assessing the virus replication after methylosome inhibition. (AU)