Open AccessThe NB Protein of Influenza B Virus Is Not Necessary for Virus Replication In Vitro
Author(s) -
Masato Hatta,
Yoshihiro Kawaoka
Publication year - 2003
Publication title -
journal of virology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.617
H-Index - 292
eISSN - 1070-6321
pISSN - 0022-538X
DOI - 10.1128/jvi.77.10.6050-6054.2003
Subject(s) - biology , virus , viral replication , virology , influenza a virus , mutant , orthomyxoviridae , in vitro , viral life cycle , viral matrix protein , cell culture , reverse genetics , gene , genetics
The NB protein of influenza B virus is thought to function as an ion channel and therefore would be expected to have an essential function in viral replication. Because direct evidence for its absolute requirement in the viral life cycle is lacking, we generated NB knockout viruses by reverse genetics and tested their growth properties both in vitro and in vivo. Mutants not expressing NB replicated as efficiently as the wild-type virus in cell culture, whereas in mice they showed restricted growth compared with findings for the wild-type virus. Thus, the NB protein is not essential for influenza B virus replication in cell culture but promotes efficient growth in mice.