Isolation and molecular characterization of a novel cytopathogenic paramyxovirus from tree shrews

A cytopathic infectious agent was isolated from the kidneys of an apparentl y healthy tree shrew (Tupaia belangeri) that had been captured in the area around Bangkok. The infectivity was propagated in Tupaia fibroblast and kid ney cell cultures. Paramyxovirus-like pleomorphic enveloped particles and h elical nucleocapsids were observed by electron microscopy and accordingly t he infectious agent was termed Tupaia paramyxovirus (TPMV). However, no ser ological cross-reactions were detected between TPMV and known paramyxovirus es. For the molecular characterization of TPMV an experimental strategy tha t allows the random-primed synthesis of relatively large cDNA molecules fro m viral genomic RNA was applied. Nucleotide sequence analysis of a TPMV-spe cific cDNA fragment (1544 bp) revealed two nonoverlapping partial open read ing frames corresponding to paramyxoviral N and P transcription units. Usin g modified rapid amplification of cDNA ends techniques, a substantial conti guous portion of the viral genome (4065 nt) was elucidated including the co mplete N and P/V/C genes. The coding strategy of TPMV as well as significan t amino acid sequence homologies clearly indicates an evolutionary relation ship between TPMV and members of the genus Morbillivirus. Highest homologie s were detected between TPMV and Hendra virus (equine morbillivirus), which recently emerged in Australia, causing outbreaks of fatal respiratory and neurological disease in horses and humans. (C) 1999 Academic Press.