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Hepatitis delta virus (HDV) is unique relative to all known animal viruses, especially in terms of its ability to redirect host RNA polymerase(s) to transcribe its 1,679-nucleotide (nt) circular RNA genome. During replication there accumulates not only more molecules of the genome but also its exact complement, the antigenome. In addition, there are(More)
The genome of hepatitis delta virus (HDV) is a 1,679-nucleotide (nt) single-stranded circular RNA that is predicted to fold into an unbranched rodlike structure. During replication, two complementary RNAs are also detected: an exact complement, referred to as the antigenome, and an 800-nt polyadenylated RNA that could act as the mRNA for the delta antigen.(More)
The circular RNA genome of hepatitis delta virus (HDV) can fold into an unbranched rodlike structure. We mutagenized the two ends of this structure and assayed the effects on the ability of the genomes to replicate and accumulate processed RNA transcripts in transfected cells. The top end, defined as that nearest to the 5' end of the putative mRNA for delta(More)
Intrinsic to the life cycle of hepatitis delta virus (HDV) is the fact that its RNAs undergo different forms of posttranscriptional RNA processing. Transcripts of both the genomic RNA and its exact complement, the antigenomic RNA, undergo ribozyme cleavage and RNA ligation. In addition, antigenomic RNA transcripts can undergo 5' capping, 3' polyadenylation,(More)
Astrocytomas are heterogeneous intracranial glial neoplasms ranging from the highly aggressive malignant glioblastoma multiforme (GBM) to the indolent, low-grade pilocytic astrocytoma. We have investigated whether DNA microarrays can identify gene expression differences between high-grade and low-grade glial tumors. We compared the transcriptional profile(More)
Molecular classification of tumors based on their gene expression profiles promises to significantly refine diagnosis and management of cancer patients. The establishment of organ-specific gene expression patterns represents a crucial first step in the clinical application of the molecular approach. Here, we report on the gene expression profiles of 154(More)
Hepatitis B virus (HBV) and hepatitis delta virus (HDV) are major sources of acute and chronic hepatitis. HDV requires the envelope proteins of HBV for the processes of assembly and infection of new cells. Both viruses are able to infect hepatocytes though previous studies have failed to determine the mechanism of entry into such cells. This study began(More)
In animal cells, small interfering RNAs (siRNA), when exogenously provided, have been reported to be capable of inhibiting replication of several different viruses. In preliminary studies, siRNA species were designed and tested for their ability to act on the protein expressed in Huh7 cells transfected with DNA-directed mRNA constructs containing hepatitis(More)
Replication of the genome of hepatitis delta virus (HDV) requires RNA-directed RNA synthesis using a host polymerase(s). This manuscript reviews the relevant published evidence. It also provides two new studies, both of which made use of transiently transfected Huh7 cells undergoing HDV RNA-directed RNA synthesis. For the first study, RNA transcription(More)
The endonuclease dicer cleaves RNAs that are 100% double stranded and certain RNAs with extensive but <100% pairing to release approximately 21-nucleotide (nt) fragments. Circular 1,679-nt genomic and antigenomic RNAs of human hepatitis delta virus (HDV) can fold into a rod-like structure with 74% pairing. However, during HDV replication in hepatocytes of(More)