DisplayTitle

Interaction Between Tomato spotted wilt virus N Protein Monomers Involves Nonelectrostatic Forces Governed by Multiple Distinct Regions in the Primary Structure

First, third, and fourth authors: Department of Biology, Colgate University, 13 Oak Drive, Hamilton, NY 13346; second author: Functional Genomics Division, Department of Plant Systems Biology, Flanders Interuniversity Institute of Biotechnology (VIB), Ghent University, Technologie Park, 927, Ghent B-9052 Belgium; and fifth author: Department of Entomology, University of Wisconsin, 1630 Linden Drive, Madison 53706

The ambisense RNA genome of Tomato spotted wilt virus (TSWV) isby interaction with numerous copies of the virus encoded nucleocapsid (N) protein to form a subvirion structure called a ribonucleo-protein (RNP). RNPs are central to the viral replication cycle because they, and not free viral RNA, serve as templates for viral gene expression and genome replication. N protein monomers bind to viral RNA molecules in a cooperative manner. We have examined regions of the N protein that are involved in the N-N interactions that likely contribute to the cooperative binding of N to viral RNA. We created random and alanine scanning mutants of N and then screened the mutants for defects in N-N interaction using reverse and forward yeast two-hybrid assays. Our experiments identified residues in three distinct regions of the primary structure of the protein, residues 42 to 56, 132 to 152, and in the C-terminal 26 amino acids, that contribute to N-N dimerization or multimerization.interactions between N monomers mediated by the residues we identified are of a nonelectrostatic nature.

Additional keyword: tospovirus.