Nucleoprotein/NP Protein, H1N1 (Q5UEW0, sf9, His)

Nucleoprotein/NP coordinates critical steps in the influenza virus life cycle. It encapsulates negative-strand viral RNA, forming a protective ribonucleoprotein (RNP) template for transcription and replication. Nucleoprotein/NP Protein, H1N1 (Q5UEW0, sf9, His) is the recombinant Virus-derived Nucleoprotein/NP protein, expressed by Sf9 insect cells , with C-His labeled tag. The total length of Nucleoprotein/NP Protein, H1N1 (Q5UEW0, sf9, His) is 498 a.a., with molecular weight of ~57.7 kDa.

Nucleoprotein (NP) plays a crucial role in encapsidating the negative strand viral RNA, offering protection against nucleases. This encapsidated genomic RNA, known as the ribonucleoprotein (RNP), serves as a template for transcription and replication. To initiate an infectious cycle, the RNP needs to be localized in the host nucleus; however, its large size prevents diffusion through the nuclear pore complex. NP contains at least two nuclear localization signals that actively facilitate RNP import into the nucleus via the cellular importin alpha/beta pathway. Subsequently, the nuclear export of RNPs is mediated by viral proteins NEP, which interacts with M1 that binds to nucleoproteins. It is also possible that NP directly binds to host exportin-1/XPO1, actively participating in RNPs nuclear export. The interaction between M1 and RNP appears to mask NP's nuclear localization signals. However, upon infecting a new cell, M1 dissociates from RNP due to acidification driven by M2 protein, thereby revealing NP's nuclear localization signals and facilitating targeted RNP transport into the nucleus. Additionally, NP forms homomultimers to create the nucleocapsid and may bind to viral genomic RNA. The protein-RNA interactions involve a combination of electrostatic interactions between positively charged residues and the phosphate backbone, as well as planar interactions between aromatic side chains and bases.

Virus

Sf9 insect cells

C-His

Q5UEW0 (M1-N498)

/

Approximately 57.7 kDa

Greater than 85% as determined by reducing SDS-PAGE

<1 EU/μg, determined by LAL method.