Metabolic labeling of woodchuck hepatitis B virus X protein in naturally infected hepatocytes reveals a bimodal half-life and association with the nuclear framework.
In order to identify potential sites of hepadnavirus X protein action, we have investigated the subcellular distribution and the stability of woodchuck hepatitis virus (WHV) X protein (WHx) in primary hepatocytes isolated from woodchucks with persistent WHV infection. In vivo cell labeling and cell fractionation studies showed that the majority of WHx is a soluble cytoplasmic protein while a minor part of newly synthesized WHx is associated with a nuclear framework fraction (20%) and with cytoskeletal components (5 to 10%). Pulse-chase experiments revealed that cytoplasmic WHx has a short half-life and decays with bimodal kinetics (approximately 20 min and 3 h). The rates of association and turnover of nucleus-associated WHx suggest that compartmentalization may be responsible for the bimodal turnover observed in the cytoplasm.
Marion Bessin Liver Research Center, Department of Medicine, Jack and Pearl Resnick Campus of the Albert Einstein College of Medicine, Bronx, New York 10461, USA.
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M
Dandri
J
J
Petersen
R J
RJ
Stockert
T M
TM
Harris
C E
CE
Rogler
D000818:Animals; D002451:Cell Compartmentation; D002467:Cell Nucleus / Q000378:metabolism / Q000821:virology; D003600:Cytosol / Q000378:metabolism / Q000821:virology; D006207:Half-Life; D006509:Hepatitis B / Q000378:metabolism / Q000662:veterinary* / Q000821:virology; D017919:Hepatitis B Virus, Woodchuck / Q000378:metabolism* / Q000472:pathogenicity; D007700:Kinetics; D008099:Liver / Q000378:metabolism* / Q000821:virology*; D008392:Marmota; D012995:Solubility; D013347:Subcellular Fractions / Q000378:metabolism / Q000821:virology; D015534:Trans-Activators / Q000378:metabolism*; D014764:Viral Proteins / Q000378:metabolism*
D015534:Trans-Activators; D014764:Viral Proteins; C090237:protein X, Woodchuck hepatitis B virus