Submitted to: Virus Research
Publication Type: Peer reviewed journal
Publication Acceptance Date: 10/29/2002
Publication Date: 3/1/2003
Citation: SHIELL, B.J., GARDNER, D.R., CRAMERI, G., EATON, B.T., WOJTEK, M.P. SITES OF PHOSPHORYLATION OF P AND V PROTEINS FROM HENDRA AND NIPAH VIRUSES: NEWLY EMERGED MEMBERS OF PARAMYXOVIRIDAE. VIRUS RESEARCH. 2003. Interpretive Summary: Recently two closely related members of the family Paramyxoviridae, now known as Hendra virus (HeV) and Nipah virus (NiV), emerged in Australia and Malaysia. HeV, previously known as equine morbillivirus, emerged as the causative agent of an outbreak of fatal respiratory disease in horses and man in Australia in 1994 and also causes fatal systemic infections in laboratory horses, cats and guinea pigs and sub-clinical systemic infections in flying foxes. NiV emerged in 1998/1999 in Malaysia and Singapore causing fatal encephalitis in humans and a respiratory syndrome in pigs. The phosoproteins in all paramyxoviruses are highly phosphorylated in comparison to other viral proteins. The functional significance the P protein phosphorylation is not clear and this in part may stem from the lack of information on the precise location of the phosphorylation sites in the protein. A strategy for comprehensive comparison of viral protein sequences with the products predicted from the corresponding gene sequences is described and the phosphorylation status and general characterization of the P and V proteins of two new, closely related paramyxoviruses, HeV and NiV, were determined.
Technical Abstract: Hendra (HeV) and Nipah (NiV) viruses are newly emerged, zoonotic viruses and their genomes have nucleotide and predicted amino acid homologies placing them in the subfamily Paramyxovirinae. They polymerse-associated phosphorproteins (P proteins) of paramyxoviruses have been shown, by direct and indirect methods, to be highly phosphorylated. In this study, a comprehensive comparison of in vivo phosphorylation of HeV and NiV P proteins, derived from virus particles, was achieved by a direct approach using electrospray ionization ion trap mass spectrometry (ESI-IT-MS). Phosphorylation sites for the P proteins were determined at Ser-224 and Thr-239 in HeV and at Ser-240 and Ser-472 in NiV. These phosphorylation patterns do not appear to be consistent with those reported for other paramyxoviruses. Protein V, a product of a frame shift in the P protein gene, was identified by specific antibodies in HeV preparations but not in NiV. HeV V protein was found to contain phosphoserine but not phosphorthreonine. In addition, P proteins from both viruses were found to be modified by N-terminal acetylation.