Analysis of gene junction sequences of human parainfluenza virus type 3.

Abstract

Transcription of the human parainfluenza virus type 3 (hPIV3) genome occurs by a sequential stop-start mechanism which is directed by short conserved sequence elements found at the boundary of the each of the hPIV3 genes, yielding several monocistronic mRNAs. The general aim of this project was to begin to elucidate the role of these cis acting transcription regulatory sequences. A technique called minigenome rescue, which allows the in vitro manipulation and analysis of cDNA representing minigenome analogs of the hPIV3 genome, was used. The requirement of the rule of six for efficient rescue of hPIV3 minigenomes was verified using a series of monocistronic cDNAs. Minigenomes whose total length was a multiple of six nt (6n) were rescued more efficiently than minigenomes that were not 6n nt in length, as assayed by CAT activity. Removal of the eight extra nt from the M/F junction reduced the frequency of transcriptional readthrough to the level seen for the other hPIV3 gene junctions. (Abstract shortened by UMI.)