title: A cellular homolog of hepatitis delta antigen: implications for viral replication and evolution.
abstract: Hepatitis delta virus (HDV) is a pathogenic human virus whose RNA genome and replication cycle resemble those of plant viroids. However, viroid genomes contain no open reading frames, whereas HDV RNA encodes a single protein, hepatitis delta antigen (HDAg), which is required for viral replication. A cellular gene whose product interacts with HDAg has now been identified, and this interaction was found to affect viral genomic replication in intact cells. DNA sequence analysis revealed that this protein, termed delta-interacting protein A (DIPA), is a cellular homolog of HDAg. These observations demonstrate that a host gene product can modulate HDV replication and suggest that HDV may have evolved from a primitive viroidlike RNA through capture of a cellular transcript.
authors.affiliation: Department of Microbiology, University of California, San Francisco, CA 94143, USA.
authors.forename: R
authors.initials: R
authors.lastname: Brazas
authors.forename: D
authors.initials: D
authors.lastname: Ganem
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000595:Amino Acid Sequence; D005075:Biological Evolution; D002352:Carrier Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D002460:Cell Line; D003001:Cloning, Molecular; D016679:Genome, Viral; D018963:Hepatitis Antigens / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D003698:Hepatitis Delta Virus / Q000235:genetics* / Q000502:physiology; D035923:Hepatitis delta Antigens; D006801:Humans; D008099:Liver / Q000737:chemistry; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000235:genetics; D012367:RNA, Viral / Q000235:genetics; D012097:Repressor Proteins; D016415:Sequence Alignment; D014162:Transfection; D014407:Tumor Cells, Cultured; D014772:Viroids / Q000235:genetics; D014779:Virus Replication
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C101409:CCDC85B protein, human; D002352:Carrier Proteins; D018963:Hepatitis Antigens; D035923:Hepatitis delta Antigens; D012333:RNA, Messenger; D012367:RNA, Viral; D012097:Repressor Proteins; C442244:hepatitis delta virus large antigen