Influenza virus nucleoprotein (NP) is associated with the genome RNA, forming ribonucleoprotein cores. To identify the amino acid sequence involved in RNA binding, we performed Northwestern blot analysis with a set of N- and C-terminal deletion mutants of NP produced in Escherichia coli. The RNA binding region has been mapped between amino acid residues 91 and 188, a stretch of residues that co...

Natural killer (NK) cells are important players in the innate immune response against influenza A virus and the activating receptor NKp46, which binds hemagglutinin on the surface of infected cells, has been assigned a role in this context. As pigs are natural hosts for influenza A viruses and pigs possess both NKp46- and NKp46+ NK cells, they represent a good animal model for studying the role...

The influenza A virus NEP (NS2) protein is an structural component of the viral particle. To investigate whether this protein has an effect on viral RNA synthesis, we examined the expression of an influenza A virus-like chloramphenicol acetyltransferase (CAT) RNA in cells synthesizing the four influenza A virus core proteins (nucleoprotein, PB1, PB2, and PA) and NEP from recombinant plasmids. I...

Influenza virus strains are often pleiomorphic, a characteristic that is largely attributed to specific residues in matrix protein 1 (M1). Although the mechanism by which M1 controls virion morphology has not yet been defined, it is suggested that the M1 interaction with other viral proteins plays an important role. In this study, we rescued recombinant virus WSN-AichiM1 containing the spherica...

Influenza A virus-specific cytotoxic T lymphocytes (CTL) capable of lysing cells infected with any influenza A virus ("cross-reactive CTL") constitute a major portion of the host CTL response to influenza. The viral nucleoprotein (NP), a major internal virion structural protein, has been implicated as a possible target antigen for cross-reactive CTL. To directly examine CTL recognition of NP, a...

The nucleoprotein (NP) of influenza B virus is 50 amino acids longer at the N-terminus than influenza A virus NP and lacks homology to the A virus protein over the first 69 residues. We have deleted the N-terminal 51 and 69 residues of the influenza B/Ann Arbor/1/66 virus NP and show that nuclear accumulation of the protein is unaffected. This indicates that the nuclear localization signal is n...

SUKENO, N., OTSUKI, Y., KONNo, J. , YAMANE, N., ODAGIRI, T., ARIKAWA, J. and ISHIDA, N. Anti-Nucleoprotein Antibody Response in Influenza A Infection. Tohoku J. exp. Med., 1979 , 128 (3). 241-249 The nucleoprotein (NP) antigen isolated from influenza A virus by solubilization with Triton X-100 (TX-100) and further electrophoresis with SDS-cellulose acetate membrane gave a single band on SDS-pol...

Canine influenza is a highly contagious respiratory infection of dogs caused by the Influenza A Virus (IAV), characterized cough, sneeze, nasal secretions, and inappetence. Infections can be mild, severe or fatal. Aquatic birds constitute natural reservoir for IAV, which transmitted to terrestrial birds, including poultry. IAV has also emerged in other mammalian species, humans, swine, horses, ...

In November 2016, an influenza A(H5N8) outbreak caused deaths of wild birds and domestic poultry in Germany. Clade 2.3.4.4 virus was closely related to viruses detected at the Russia-Mongolia border in 2016 but had new polymerase acidic and nucleoprotein segments. These new strains may be more efficiently transmitted to and shed by birds.

The genome of influenza A viruses consists of eight segments of single-stranded, negative-sense RNA that are encapsidated as individual rod-shaped ribonucleoprotein complexes (RNPs). Each RNP contains a viral RNA, a viral polymerase and multiple copies of the viral nucleoprotein (NP). Influenza A virus RNPs play important roles during virus infection by directing viral RNA replication and trans...