Cell cycle arrest mediated by hepatitis delta antigen.
Hepatitis delta antigen (HDAg) is the only viral-encoded protein of the hepatitis delta virus (HDV). This protein has been extensively characterized with respect to its biochemical and functional properties. However, the molecular mechanism responsible for persistent HDV infection is not yet clear. Previously, we reported that overexpression of HDAg protects insect cells from baculovirus-induced cytolysis [Hwang, S.B. Park, K.-J. and Kim, Y.S. (1998) Biochem. Biophys. Res. Commun. 244, 652-658]. Here we report that HDAg mediates cell cycle arrest when overexpressed in recombinant baculovirus-infected insect cells. Flow cytometry analysis has shown that HDAg expression in Spodoptera frugiperda cells causes an accumulation of substantial amounts of polyploid DNA in the absence of cell division. This phenomenon may be partly responsible for the persistent infection of chronic HDV patients.
Hwang
S B
SB
Institute of Environment and Life Science, The Hallym Academy of Sciences, Hallym University, Chuncheon, South Korea. sbhwang@sun.hallym.ac.kr
Park
K J
KJ
D000818:Animals; D002453:Cell Cycle; D002455:Cell Division; D002460:Cell Line; D002470:Cell Survival; D004247:DNA / Q000032:analysis; D018963:Hepatitis Antigens / Q000235:genetics / Q000378:metabolism*; D003698:Hepatitis Delta Virus / Q000378:metabolism*; D035923:Hepatitis delta Antigens; D011123:Polyploidy; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D018411:Spodoptera / Q000166:cytology; D017361:Viral Nonstructural Proteins / Q000235:genetics / Q000378:metabolism; D012324:RNA-Dependent RNA Polymerase
D004247:DNA; D018963:Hepatitis Antigens; D035923:Hepatitis delta Antigens; D011993:Recombinant Fusion Proteins; D017361:Viral Nonstructural Proteins; C442244:hepatitis delta virus large antigen; C087036:NS-5 protein, hepatitis C virus; D012324:RNA-Dependent RNA Polymerase