Domains of human respiratory syncytial virus P protein essential for homodimerization and for binding to N and NS1 protein

In this report we used the two-hybrid technique to test for binding among h uman respiratory syncytial virus (HRSV) proteins involved in the control of viral replication. Besides the expected positive interactions for the nucl eoprotein (N) with itself and the phosphoprotein (P), our results also demo nstrated P-P interaction and P-NS1 binding. However, no interactions have b een detected for the matrix protein M, the M2-1 and the M2-2 protein neithe r with each other nor in combination with the phosphoprotein P, the nucleop rotein N or the non-structural protein NS1. While the N-P interaction was a bolished by N- and C-terminal deletions of both partners, C-terminal deleti on mutants of P were still able to form homodimers. In contrast, the C-term inal region of P turned out to be essential for binding of NS1. N-N interac tion was disrupted by any of the N- and C-terminal deletions.