Non-structural protein 2/NS2 Protein, H1N1 (His)

Non-structural protein 2/NS2 Protein assumes a crucial role in the influenza virus life cycle by mediating the nuclear export of encapsidated genomic RNAs, acting as a vital adapter between viral ribonucleoprotein complexes (RNPs) and the host cell's nuclear export machinery. Despite lacking intrinsic RNA-binding activity, NS2 includes a C-terminal M1-binding domain that allows indirect recognition of RNPs bound to the viral protein M1. This indirect recognition mechanism ensures that genomic RNPs are not prematurely exported from the host nucleus before sufficient quantities of viral mRNA and progeny genomic RNA have been synthesized, as protein M1 is limited in the early stages of infection. Moreover, NS2 facilitates the entry of RNPs into the host cytoplasm only when associated with the M1 protein, which guides them to the plasma membrane. Additionally, NS2 may down-regulate viral RNA synthesis when overproduced and interacts with M1, while also potentially interacting with host nucleoporin RAB/HRB and exportin XPO1/CRM1, further emphasizing its intricate role in orchestrating influenza virus replication.