Fig 8. Model of PLSCR1-mediated inhibition of the nuclear import of influenza NP.

In the cytoplasm, influenza virus NP, derived from newly synthesized NP or incoming vRNP, is bound by the heterodimeric import receptor, importin α/importin β, leading to its transport into the nucleus through the nuclear pore; in the presence of PLSCR1, an integrative complex among NP, PLSCR1, and importin α is formed in the cytoplasm that prevents importin α and importin β from forming a functional nuclear import receptor complex, thereby suppressing the nuclear import of NP.