- 作者: Ken-Lin Chen chun-Ming chen chwen-Ming Shih Huey-Lan Huang Yan-Hwa Wu Lee chungming Chang Szecheng J.Lo
- 作者服務機構: institute of Microbiology and Immunology, Institute of Biochemistry, National Yang-Ming University, Division of Molecular and Genomic Medicine research, National Health Research Institute, Taipei, Taiwan, ROC
- 中文摘要: --
- 英文摘要: Hepadnaviruses and retroviruses are evolutionarily re-lated families because they both require a process ofreverse transcription for genome replication. However,hepadnaviruses produce polymerase (pol) and core pro-teins separately, while retroviruses synthesize a gag-polfusion protein that is subsequently cleaved by a virallyencoded protease to release a functional polymerase. Totest whether an additional sequence at the N-terminus ofpol in hepatitis B virus (HBV) interferes with its function,we created two plasmids expressing core-pol fusion pro-teins, core144-pol and core31-pol. Secreted particles ob-tained from HuH-7 cells, which were cotransfected with acore-pol fusion protein-expressing plasmid and a core-expressing plasmid, showed a positive signal of HBVDNA by the endogenous polymerase assay, indicatingthat the core-pol fusion proteins retain DNA priming,polymerization and RNase H activities.The fusion pro-tein was detected in the cytoplasm of transfected cellsand in secreted virions by immunoprecipitation. Further-more, we found by immunofluorescence staining thatthe HBV core-pol fusion protein colocalized with the hep-atitis C virus (HCV) core protein in cytoplasm and in lipiddroplets. Immunoprecipitation studies showed that theanti-HCV core complex contained the HBV core-pol fu-sion protein while the anti-HBV pol complex containedthe HCV core protein, which supports the hypothesis thatthe HCV core protein can form a complex with the HBVcore-pol fusion protein.
- 中文關鍵字: --
- 英文關鍵字: Endogenous polymerase activity. Evolutionary distance. Hepatitis C virus core protein Immunofluorescence microscopy. reverse transcription. Pol localization