IAV-NP

The Influenza A virus nucleoprotein (NP) is a critical component of the viral replication machinery. It plays a multifaceted role in the virus’s life cycle, including encapsidating the viral RNA genome and interacting with host cell machinery to facilitate viral replication and transcription. Recombinant nucleoprotein is a form of this protein that is produced through recombinant DNA technology, allowing for its use in various research and therapeutic applications.

The nucleoprotein of Influenza A virus is a highly conserved protein among different strains of the virus. It consists of approximately 498-501 amino acids and has a molecular mass of around 56.7 kDa . The NP forms large, RNA-bound, helical filaments and acts as a scaffold for additional viral proteins . It contains two nuclear localization signals (NLSs) that are crucial for its function: a well-studied monopartite NLS1 and a less-characterized bipartite NLS2 .

The NP is essential for the replication and transcription of the viral RNA genome. It encapsidates the viral RNA, forming ribonucleoprotein (RNP) complexes that are necessary for the synthesis of viral RNA. The NP also interacts with the viral polymerase complex, facilitating the transcription and replication of the viral genome .

Recombinant nucleoprotein can be produced using various expression systems, including Escherichia coli and baculovirus-insect cell systems . The recombinant protein is often tagged with polyhistidine to facilitate purification. For example, a DNA sequence encoding the NP from the Influenza A virus (A/Puerto Rico/8/34/Mount Sinai (H1N1)) can be fused with a polyhistidine tag at the C-terminus and expressed in baculovirus-insect cells . The resulting protein can be purified and used for various applications, including vaccine development and diagnostic assays.

1. Vaccine Development: Recombinant NP has been explored as a potential candidate for universal influenza vaccines. Studies have shown that NP-based vaccines can elicit robust immune responses and provide cross-protection against different influenza strains .
2. Diagnostic Assays: Recombinant NP is used in serological assays to detect antibodies against Influenza A virus in clinical samples. These assays are crucial for diagnosing influenza infections and monitoring immune responses to vaccination.
3. Research: Recombinant NP is widely used in research to study the molecular mechanisms of influenza virus replication and host interactions. It serves as a valuable tool for investigating the structure-function relationships of viral proteins and developing antiviral therapeutics.