An RNA helicase, RHIV -1, induced by porcine reproductive and respiratory syndrome virus (PRRSV) is mapped on porcine chromosome 10q13.

The impact of porcine reproductive and respiratory syndrome virus (PRRSV) infection on porcine alveolar macrophages (Mo) was examined by differential display reverse transcription PCR (DDRT-PCR). A PRRSV-induced expressed gene tag (EST) was used to isolate and identify a single cDNA clone from a library prepared from porcine peripheral blood. Rapid amplification of cDNA ends (RACE) was employed to clone a 1.5 kb fragment at the 5' end of the mRNA. DNA sequencing identified an open reading frame (ORF) of 2820 bp. Deduced amino acid sequence revealed the eight conserved domains characteristic of the DEAD/H box protein superfamily. The putative porcine RNA helicase induced by virus (RHIV -1) showed 84% amino acid similarity to human retinoic acid-induced gene (RIG-I). Porcine RHIV -1 transcripts were ubiquitously expressed in various pig tissues, while in PRRSV-infected pigs, higher expression was observed in several tissues persistent for PRRSV. These data indicate the association of PRRSV genome replication with enhaced host cell RNA helicase gene expression. Finally, the RHIV -1 gene was localized on porcine chromosome 10q13 between markers SSC25A02 and SWR334 via somatic cell panel and radiation hybrid (RH) mapping strategies.