The 195- and 214-amino-acid (aa) forms of the delta protein (deltaAg-S and deltaAg-L, respectively) of hepatitis delta virus (HDV) differ only in the 19-aa C-terminal extension unique to deltaAg-L. deltaAg-S is needed for genome replication, while deltaAg-L is needed for particle assembly. These proteins share a region at aa 12 to 60, which mediates protein-protein interactions essential for HD...

The secondary structures proposed for the cis-acting hepatitis delta virus (HDV) ribozymes contain four duplex regions, three sequences joining the duplexes and two hairpin loops. The core and active site of the ribozyme could be formed by portions of the joining sequences, J1/4 and J4/2, together with one of the hairpin loops, L3. To establish the core region and define essential bases within ...

In elucidating function of two important single-stranded regions [SSrA (726-731 nt) and SSrB (762-766 nt)] derived mainly from three secondary structure models in genomic hepatitis delta virus (HDV) ribozyme possessing self-cleavage activity, we have constructed several random mutants at those two regions on the HDV88 molecule (683-770 nt) by oligonucleotide-directed mutagenesis. When self-clea...

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 inhibitors were added to the transfected c...

An RNA fold is the result of packing together two or more coaxial helical stacks. To date, four RNA folds have been determined at near-atomic resolution by X-ray crystallography: transfer RNA, the hammerhead ribozyme, the P4-P6 domain of the Tetrahymena group I intron, and the hepatitis delta virus ribozyme. All four folds result in RNAs that are considerably more compact than isolated A-form d...