Endogenous Promoters Can Direct the Transcription of Hepatitis Delta Virus RNA from a Recircularized cDNA Template

摘要: Abstract Transcription and replication of hepatitis delta virus (HDV) RNA is thought to be performed by host polymerase II. The mechanism which enables II use as a template unclear. However, since extensive intramolecular complementarity allows HDV form rod-shaped structure, it possible that the mostly double-stranded may resemble DNA in can thus used template. To investigate this possibility, we examined whether cDNA counterpart contains promoter drive transcription RNA. Circularized monomers cDNA, when transfected into various cell lines, were found generate both monomeric dimeric forms antigen at levels comparable those generated with multimers under control SV40 late promoter, suggesting endogenous promoters. Using chloramphenicol acetyltransferase human growth hormone reporter genes, specific activity for synthesis antigenomic was localized 29-nucleotide region (nucleotides 1650-1679), although an additional 224-nucleotide upstream also necessary maximum activity. Similarly, genomic 160-nucleotide around position 1679 overlapped region. Since these regions are highly conserved RNA,they represent promoters recognized This result suggests convenient method, using circularized monomer study replication.