5DIL: Crystal Structure Of The Effector Domain Of The Ns1 Protein From Influenza Virus B

Influenza viruses cause a highly contagious respiratory disease in humans. The NS1 proteins of influenza A and B viruses (NS1A and NS1B proteins, respectively) are composed of two domains, a dimeric N-terminal domain and a C-terminal domain, connected by a flexible polypeptide linker. Here we report the 2.0-A X-ray crystal structure and nuclear magnetic resonance studies of the NS1B C-terminal domain, which reveal a novel and unexpected basic RNA-binding site that is not present in the NS1A protein. We demonstrate that single-site alanine replacements of basic residues in this site lead to reduced RNA-binding activity, and that recombinant influenza B viruses expressing these mutant NS1B proteins are severely attenuated in replication. This novel RNA-binding site of NS1B is required for optimal influenza B virus replication. Most importantly, this study reveals an unexpected RNA-binding function in the C-terminal domain of NS1B, a novel function that distinguishes influenza B viruses from influenza A viruses.
PDB ID: 5DILDownload
MMDB ID: 142076
PDB Deposition Date: 2015/9/1
Updated in MMDB: 2017/10
Experimental Method:
x-ray diffraction
Resolution: 2.01  Å
Source Organism:
Similar Structures:
Biological Unit for 5DIL: monomeric; determined by author and by software (PISA)
Molecular Components in 5DIL
Label Count Molecule
Protein (1 molecule)
Non-structural Protein 1
Molecule annotation
Chemicals (8 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB