Activation of the CKI-CDK-Rb-E2F pathway in full genome hepatitis C virus-expressing cells.
Hepatitis C virus (HCV) causes persistent infection in hepatocytes, and this infection is, in turn, strongly associated with the development of hepatocellular carcinoma. To clarify the mechanisms underlying these effects, we established a Cre/loxP conditional expression system for the precisely self-trimmed HCV genome in human liver cells. Passage of hepatocytes expressing replicable full-length HCV (HCR6-Rz) RNA caused up-regulation of anchorage-independent growth after 44 days. In contrast, hepatocytes expressing HCV structural, nonstructural, or all viral proteins showed no significant changes after passage for 44 days. Only cells expressing HCR6-Rz passaged for 44 days displayed acceleration of CDK activity, hyperphosphorylation of Rb, and E2F activation. These results demonstrate that full genome HCV expression up-regulates the CDK-Rb-E2F pathway much more effectively than HCV proteins during passage.
Tsukiyama-Kohara
Kyoko
K
Department of Microbiology and Cell Biology and Cell Physiology, Tokyo Metropolitan Institute of Medical Science, 3-18-22 Honkomagome, Bunkyo-ku, Tokyo 113-8613, Japan.
Toné
Shigenobu
S
Maruyama
Isao
I
Inoue
Kazuaki
K
Katsume
Asao
A
Nuriya
Hideko
H
Ohmori
Hiroshi
H
Ohkawa
Jun
J
Taira
Kazunari
K
Hoshikawa
Yutaka
Y
Shibasaki
Futoshi
F
Reth
Michael
M
Minatogawa
Yohsuke
Y
Kohara
Michinori
M
D015153:Blotting, Western; D047388:Casein Kinases; D002453:Cell Cycle; D018797:Cell Cycle Proteins; D002455:Cell Division; D002460:Cell Line; D002469:Cell Separation; D003001:Cloning, Molecular; D050759:Cyclin-Dependent Kinase Inhibitor p21; D018844:Cyclin-Dependent Kinases / Q000378:metabolism*; D016213:Cyclins / Q000378:metabolism; D018076:DNA, Complementary / Q000378:metabolism; D004268:DNA-Binding Proteins; D050684:E2F Transcription Factors; D005434:Flow Cytometry; D015967:Gene Expression Regulation, Viral; D017930:Genes, Reporter; D016679:Genome, Viral; D016174:Hepacivirus / Q000235:genetics*; D022781:Hepatocytes / Q000378:metabolism; D006801:Humans; D015151:Immunoblotting; D008099:Liver / Q000821:virology*; D008957:Models, Genetic; D020411:Oligonucleotide Array Sequence Analysis; D010766:Phosphorylation; D010957:Plasmids / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011494:Protein Kinases / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D016160:Retinoblastoma Protein / Q000378:metabolism*; D013997:Time Factors; D014157:Transcription Factors / Q000378:metabolism*; D014162:Transfection; D015854:Up-Regulation
C493956:CDKN1A protein, human; D018797:Cell Cycle Proteins; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D050684:E2F Transcription Factors; D012333:RNA, Messenger; D016160:Retinoblastoma Protein; D014157:Transcription Factors; D011494:Protein Kinases; D047388:Casein Kinases; D018844:Cyclin-Dependent Kinases