Sequence of the hemagglutinin-neuraminidase gene of human parainfluenza virus type 1.

The nucleotide sequence of the gene encoding the hemagglutinin-neuraminidase (HN) glycoprotein of human parainfluenza virus type 1 (PI1) was determined from cDNA clones derived from poly(A)+ RNA extracted from infected cells. A single open reading frame in the sequence was found to encode a putative protein of 575 amino acids with a calculated molecular weight of 63,960. The predicted amino acid sequence contains ten potential sites for N-linked glycosylation and one major hydrophobic region located 35 amino acids from the amino terminus, which appears to be the signal-anchor domain of HN. Comparison of the amino acid sequence with the HN glycoproteins of other paramyxoviruses indicated that the PI1 HN protein is most closely related to the Sendai virus (SV) HN protein.