The nine C-terminal amino acids of the respiratory syncytial virus protein P are necessary and sufficient for binding to ribonucleoprotein complexes in which six ribonucleotides are contacted per N protein protomer.

Tran, T. et al. (2007) The nine C-terminal amino acids of the respiratory syncytial virus protein P are necessary and sufficient for binding to ribonucleoprotein complexes in which six ribonucleotides are contacted per N protein protomer. Journal of General Virology, 88(1), pp. 196-206. (doi: 10.1099/vir.0.82282-0)

Abstract

The respiratory syncytial virus (RSV) phosphoprotein (P) is a major polymerase co-factor that interacts with both the large polymerase fragment (L) and the nucleoprotein (N). The N-binding domain of RSV P has been investigated by co-expression of RSV P and N proteins in Escherichia coli. Pull-down assays performed with a series of truncated forms of P fused to glutathione S-transferase (GST) revealed that the region comprising the last nine C-terminal amino acid residues of P (233-DNDLSLEDF-241) is sufficient for efficient binding to N. Site-directed mutagenesis shows that the last four residues of this peptide are crucial for binding and must be present at the end of a flexible C-terminal tail. The presence of the P oligomerization domain (residues 100-160) was an important stabilizing factor for the interaction. The tetrameric full-length P fused to GST was able to pull down both helical and ring structures, whereas a monomeric C-terminal fragment of P (residues 161-241) fused to GST pulled down exclusively RNA-N rings. Electron-microscopy analysis of the purified rings showed the presence of two types of complex: undecamers (11N) and decamers (10N). Mass-spectrometry analysis of the RNA extracted from rings after RNase A treatment showed two peaks of 22,900 and 24,820 Da, corresponding to a mean RNA length of 67 and 73 bases, respectively. These results suggest strongly that each N subunit contacts 6 nt, with an extra three or four bases further protected from nuclease digestion by the ring structure at both the 5' and 3' ends.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Bhella, Professor David
• Authors: Tran, T., Castagné, N., Bhella, D., Varela, P.F., Bernard, J., Chilmonczyk, S., Berkenkamp, S., Benhamo, V., Grznarova, K., Grosclaude, J., Nespoulos, C., Rey, F.A., and Eléouët, J.
• College/School: College of Medical Veterinary and Life Sciences > School of Infection & Immunity; College of Medical Veterinary and Life Sciences > School of Infection & Immunity > Centre for Virus Research
• Journal Name: Journal of General Virology
• Publisher: Society for General Microbiology
• ISSN: 0022-1317