 As the NP protein accumulates, the transition from the transcription to the replication occurs.The NP protein encapsidates the genomic RNA, forming a helical nucleocapsid which is the template for RNA synthesis by the viral RNA polymerase.The protein is a crusial component of the following complexes NP-P (P, phosphoprotein), NP-NP, nucleocapsid-polymerase, and RNA-NP.