Deduced Amino Acid Sequence of the Fusion Glycoprotein of Turkey Rhinotracheitis Virus has Greater Identity with that of Human Respiratory Syncytial Virus, a Pneumovirus, than that of Paramyxoviruses and Morbilliviruses

The sequence of the fusion (F) glycoprotein of turkey rhinotracheitis virus (TRTV) has been deduced from cDNA clones derived from oligo(dT)-selected infected cell RNA. The protein consists of 538 amino acids, the F2 and F1 subunits containing 102 (including the F2-F1 connecting peptide RRRR) and 436 residues, respectively. Each subunit has one potential N-linked glycosylation site. The protein has 38 to 39% amino acid identity with the F protein of respiratory syncytial virus (Pneumovirus genus) but only about half that with members of the other two genera (Paramyxovirus and Morbillivirus) in the Paramyxoviridae family. This is the first sequence evidence to support the view that TRTV is a pneumovirus, the first avian member of the genus to be described.