Measles virus phosphoprotein retains the nucleocapsid protein in the cytoplasm

Virology. 1991 Nov;185(1):299-308. doi: 10.1016/0042-6822(91)90777-9.


Measles virus (MV) proteins were efficiently expressed in COS and Vero cells from vectors based on the strong cytomegalovirus enhancer-promoter and the simian virus 40 origin of replication. When expressed alone, nucleocapsid protein (N) migrates predominantly into the nucleus whereas phosphoprotein (P) is located in the cytoplasm. Coexpression of N and P proteins results in retention of the N protein in the cytoplasm, as seen also in infected cells. The retention of N protein is due to specific interactions with the P protein since coexpression of N with either the matrix or the hemagglutinin protein had no effect. Mapping of the regions of N-P interactions on P protein revealed that the carboxy-terminal 40% of P was sufficient for specific binding to N; however, the carboxy-terminal 60% of P was required for retention of N in the cytoplasm. Thus, the V and C proteins encoded within the first half of the P gene are not involved in the cytoplasmic retention of N protein. N protein might be fortuitously targeted to the nucleus as a result of its many basic amino acids, presumably destined to interact with the MV genome. However, this set of experiments has allowed to analyze in vivo the interactions between the N and P proteins.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Base Sequence
  • Capsid / genetics*
  • Cell Line
  • Cytomegalovirus / genetics
  • Cytoplasm / physiology
  • DNA Replication
  • DNA, Viral / genetics
  • Enhancer Elements, Genetic
  • Fluorescent Antibody Technique
  • Genetic Vectors
  • Measles virus / genetics*
  • Measles virus / metabolism
  • Molecular Sequence Data
  • Oligodeoxyribonucleotides
  • Phosphoproteins / genetics*
  • Promoter Regions, Genetic
  • Simian virus 40 / genetics
  • Transfection
  • Vero Cells
  • Viral Core Proteins / genetics*


  • DNA, Viral
  • Oligodeoxyribonucleotides
  • Phosphoproteins
  • Viral Core Proteins