|Virology (2002) 304(2):291-301|
|Northeast Structural Genomics Consortium|
(click to unfold)
The N-terminal domains of the NS1 protein of influenza B virus (NS1B protein) and the NS1 protein of influenza A virus (NS1A protein) share one function: binding double-stranded RNA (dsRNA). ...
Here we show that the N-terminal domain of the NS1B protein possesses an additional function that is not shared by its NS1A counterpart: binding the ubiquitin-like ISG15 protein that is induced by influenza B virus infection. Homology modeling predicts that the dimeric six-helical N-terminal domain of the NS1B protein differs from its NS1A protein counterpart in containing large loops between helices 1 and 2 (loops 1 and 1') and between helices 2 and 3 (loops 2 and 2'). Mutagenesis establishes that residues located in loop 1/1' together with residues located in polypeptide segment 94-103 form the ISG15 protein-binding site of NS1B protein. Loop 1/1' is not required for dsRNA binding, which instead requires arginine residues R50, R53, R50', and R53' located in antiparallel helices 1 and 1'. Further, we demonstrate that the binding sites for RNA and protein are independent of each other. In particular, ISG15 and dsRNA can bind simultaneously; the binding of the ISG15 protein does not have a detectable effect on the binding of dsRNA, and vice versa.
|chemistry analogs & derivatives metabolism |
|Models, Molecular Dimerization Molecular Sequence Data RNA, Viral Cytokines Binding Sites Amino Acid Sequence Viral Nonstructural Proteins Protein Binding Ubiquitins Influenza B virus |
|28 (Last update: 04/21/2018 2:07:15pm)|
|Virology. 2002 Dec 20;304(2):291-301.|