MAPPING THE DOMAINS ON THE PHOSPHOPROTEIN OF BOVINE RESPIRATORY SYNCYTIAL VIRUS REQUIRED FOR N-P INTERACTION USING A 2-HYBRID SYSTEM

Specific interactions between the nucleocapsid protein (N) and the pho sphoprotein (P) of bovine respiratory syncytial virus (BRSV) have been investigated using a yeast-based two-hybrid system. Plasmids encoding the yeast GAL4 DNA binding domain fused with the N gene and GAL4 acti vation domain fused with the P gene were contransfected into competent yeast cells. The ability of the N and P proteins to interact in vivo was measured by activation of the lacZ reporter gene by the GAL4 trans activation region. Results indicated that the N and P protein interact very strongly in vivo. When interactions between N and various deleti on mutants of the P protein were examined, an internal region (aa 132- 168) and the highly acidic C-terminal region (aa 236-241) of the P pro tein were found to be essential for N-P interaction. In addition, the highly basic N-terminal region (amino acids 1-40) was found to be invo lved in N-P interaction to a lesser extent.