Structure and dynamics of the nucleocapsid-binding domain of the Sendai virus phosphoprotein in solution

Virology. 2004 Feb 20;319(2):201-11. doi: 10.1016/j.virol.2003.10.029.


The RNA-dependent RNA polymerase of the Sendai virus (SeV) consists of the large protein (L) and the phosphoprotein (P). P plays a crucial role in the enzyme by positioning L (which carries the polymerase activity) onto the matrix for transcription and replication formed by the RNA and the nucleoprotein, the N-RNA. P has a modular structure with distinct functional domains: an N-terminal domain involved in binding to N degrees (N that is not yet bound to RNA) and a C-terminal domain that carries the oligomerisation domain, the N-RNA binding domain and the L binding domain and that, combined with L, is active in transcription. Structural data have previously been obtained on the N-terminal domain and on the oligomerisation domain of P, but not yet on its N-RNA binding domain (also-called the X protein). Here we present an NMR and a small angle neutron scattering study of the SeV X protein. We show that this molecule presents two subdomains linked by an 11-residue linker, with the N-subdomain lacking a well-defined conformation. The 3D structure of the C-subdomain consists of three alpha-helices revealing an asymmetric charge distribution that may be important for binding to RNA-bound nucleoprotein. The structure of the entire C-terminal domain of P is modelled from its constituent parts in combination with small angle scattering data on this domain.

Publication types

  • Comparative Study

MeSH terms

  • Amino Acid Sequence
  • Magnetic Resonance Spectroscopy
  • Models, Molecular
  • Molecular Sequence Data
  • Nucleocapsid / metabolism*
  • Phosphoproteins / chemistry
  • Phosphoproteins / metabolism*
  • Protein Structure, Secondary
  • Protein Structure, Tertiary
  • Sendai virus / chemistry
  • Sendai virus / metabolism*
  • Sequence Alignment
  • Viral Proteins / chemistry
  • Viral Proteins / metabolism*


  • Phosphoproteins
  • Viral Proteins