Antisense RNAs transcribed from the upstream region of the precore/core promoter of hepatitis B virus.
The bidirectional activity of the precore/core promoter of hepatitis B virus (HBV) has been demonstrated in cultured cell lines. However, HBV antisense transcripts (asRNAs) have not been demonstrated in vivo. In the present study using liver tissue from patients with chronic hepatitis, an anchored 5'RACE mapping the 5' ends at position 1680/1681, 1655 or 1609/1602 was carried out. In limited cases, RLM-3'RACE detected asRNAs to terminate at four or five consecutive dT residues in the 0.7 kb downstream region. PCR of oligo(dT)-primed cDNA did not amplify a typical polyadenylated asRNA. RT-PCR using various primers did not detect any spliced forms. Competitive RT-PCR estimated the copy numbers of the asRNAs to be 0.05-0.4 % of total sense RNAs. All sequenced asRNAs had ORF6 but, in one patient, the asRNA initiating at position 1680/1681 had additional initiation and termination codons in front of ORF6. Therefore, asRNAs are transcribed by RNA polymerase III at a low level, encompass a dispensable ORF6 gene and might be retained in the nucleus. The endogenous asRNAs complementary to the common ends of all sense RNAs suggest antisense-mediated self-regulation of hepadnavirus.
Moriyama
Kosei
K
Department of Medicine, Fukuoka Dental College, 2-15-1 Tamura, Sawara-ku, Fukuoka 814-0193, Japan.
Hayashida
Kazuhiro
K
Department of Medicine and Biosystemic Science, Graduate School of Medical Sciences, Kyushu University, Higashi-ku, Fukuoka 812-8582, Japan.
Shimada
Mitsuo
M
Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan.
Nakano
Shuji
S
Department of Medicine and Biosystemic Science, Graduate School of Medical Sciences, Kyushu University, Higashi-ku, Fukuoka 812-8582, Japan.
Nakashima
Yoshiyuki
Y
Department of Medicine, Fukuoka Dental College, 2-15-1 Tamura, Sawara-ku, Fukuoka 814-0193, Japan.
Fukumaki
Yasuyuki
Y
Division of Disease Genes, Research Center for Genetic Information, Medical Institute of Bioregulation, Kyushu University, Fukuoka 812-8582, Japan.
D001483:Base Sequence; D015967:Gene Expression Regulation, Viral; D006512:Hepatitis B Core Antigens / Q000235:genetics / Q000378:metabolism; D006515:Hepatitis B virus / Q000235:genetics* / Q000378:metabolism; D019694:Hepatitis B, Chronic / Q000821:virology*; D006801:Humans; D008099:Liver / Q000378:metabolism; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D011498:Protein Precursors / Q000235:genetics / Q000378:metabolism; D016372:RNA, Antisense / Q000235:genetics / Q000378:metabolism*; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic; D054334:Viral Regulatory and Accessory Proteins
D006512:Hepatitis B Core Antigens; D011498:Protein Precursors; D016372:RNA, Antisense; D015534:Trans-Activators; D054334:Viral Regulatory and Accessory Proteins; C057628:hepatitis B virus X protein