Structural Insights into the Function of Influenza NS1
Zachary A. Bornholdt, Berenice Carrillo and B.V. Venkataram Prasad
from: Influenza: Molecular Virology (Edited by: Qinghua Wang and Yizhi Jane Tao). Caister Academic Press, U.K. (2010)
The non-structural protein 1 (NS1) of influenza virus is a potent antagonist of the cellular antiviral interferon (IFN) response. It is a multifunctional protein with two domains, a dsRNA binding domain (RBD) and an effector domain (ED) which interacts with various cellular proteins. Although, initially sequestration of dsRNA was considered the primary mechanism for countering IFN, subsequent studies have shown that the interactions of ED with various cellular proteins are likely involved. NS1 is shown to be a virulence determinant, especially in the highly pathogenic H5N1 viruses that are currently a threat for another influenza pandemic. Among various influenza virus strains, NS1 is relatively well conserved with major differences occurring in the linker region and the C-terminus, where several NS1 proteins contain truncations. How these differences contribute to virulence remains unknown but these differences seem to have an effect on NS1 function that may be strain specific. In recent years, substantial progress has been made toward understanding of the structural aspects of this two-domain protein. Here we review this progress and discuss the structural basis of various activities of NS1 read more ...