Research Topics
| Michael M C LaiSummaryAffiliation: University of Southern California Country: USA Publications
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Detail Information
Publications
RNA replication without RNA-dependent RNA polymerase: surprises from hepatitis delta virusMichael M C Lai
Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, 2011 Zonal Ave, HMR503C, Los Angeles, California 90033, USA
J Virol 79:7951-8. 2005- c-Jun mediates hepatitis C virus hepatocarcinogenesis through signal transducer and activator of transcription 3 and nitric oxide-dependent impairment of oxidative DNA repairKeigo Machida
Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, Los Angeles, CA 90033, USA
Hepatology 52:480-92. 2010.... 
SARS virus: the beginning of the unraveling of a new coronavirusMichael M C Lai
Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, Los Angeles, CA 90033, USA
J Biomed Sci 10:664-75. 2003..The comparative studies of other coronaviruses offer insights into the understanding of SARS virus...- Hepatitis C virus inhibits DNA damage repair through reactive oxygen and nitrogen species and by interfering with the ATM-NBS1/Mre11/Rad50 DNA repair pathway in monocytes and hepatocytesKeigo Machida
Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
J Immunol 185:6985-98. 2010..These effects may explain the oncogenicity and immunological perturbation of HCV infection... - Hepatitis C virus triggers mitochondrial permeability transition with production of reactive oxygen species, leading to DNA damage and STAT3 activationKeigo Machida
Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, Los Angeles, 90033, USA
J Virol 80:7199-207. 2006..These HCV studies thus identified ROS, along with the previously identified NO, as the primary inducers of DSBs and mitochondrial damage in HCV-infected cells... - Reactive oxygen species suppress hepatitis C virus RNA replication in human hepatoma cellsJinah Choi
Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
Hepatology 39:81-9. 2004..In conclusion, our results show that ROS can rapidly inhibit HCV RNA replication in human hepatoma cells. The increased ROS levels in hepatitis C patients may therefore play an important role in the suppression of HCV replication... - RNA-templated replication of hepatitis delta virus: genomic and antigenomic RNAs associate with different nuclear bodiesYi-Jia Li
Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, 2011 Zonal Ave, Los Angeles, CA 90033-1054, USA
J Virol 80:6478-86. 2006..These findings provide additional evidence that HDV RNA synthesis occurs in the Pol I and Pol II transcription machineries, thus extending the capability of the cellular DNA-dependent RNA polymerases to utilizing RNA as templates... - Enzymatic characterization of the full-length and C-terminally truncated hepatitis C virus RNA polymerases: function of the last 21 amino acids of the C terminus in template binding and RNA synthesisNam Viet Vo
Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, Los Angeles, California 90033-1054, USA
Biochemistry 43:10579-91. 2004..Together, these findings indicated that the HCV NS5B C(21) domain, in addition to being a membrane anchor, functions in template binding, NTP substrate selection, and modulation of terminal transferase activity... - Hepatitis C virus E2-CD81 interaction induces hypermutation of the immunoglobulin gene in B cellsKeigo Machida
Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, 2011 Zonal Ave, Los Angeles, California 90033, USA
J Virol 79:8079-89. 2005.... - Hepatitis C virus infection activates the immunologic (type II) isoform of nitric oxide synthase and thereby enhances DNA damage and mutations of cellular genesKeigo Machida
Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, 2011 Zonal Ave, Los Angeles, CA 90033, USA
J Virol 78:8835-43. 2004..NO causes DNA breaks and enhances DNA mutation. This sequence of events provides a mechanism for HCV pathogenesis and oncogenesis... - Hepatitis C virus RNA replication occurs on a detergent-resistant membrane that cofractionates with caveolin-2Stephanie T Shi
Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, California 90033, USA
J Virol 77:4160-8. 2003..We suggest that HCV RNA synthesis occurs on a lipid raft membrane structure... - Genomic but not antigenomic hepatitis delta virus RNA is preferentially exported from the nucleus immediately after synthesis and processingThomas B Macnaughton
Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, California 90033-1054, USA
J Virol 76:3928-35. 2002..These findings uncover a previously unrecognized presence of HDV RNA in the cytoplasm, which may have implications for viral RNA synthesis and packaging... - Hepatitis delta virus antigen is methylated at arginine residues, and methylation regulates subcellular localization and RNA replicationYi-Jia Li
Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, 2011 Zonal Ave, Los Angeles, CA 90033-1054, USA
J Virol 78:13325-34. 2004.... - Rolling circle replication of hepatitis delta virus RNA is carried out by two different cellular RNA polymerasesThomas B Macnaughton
Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, California 90033-1054, USA
J Virol 76:3920-7. 2002.... - Characterization of the hepatitis C virus RNA replication complex associated with lipid raftsHideki Aizaki
Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, 2011 Zonal Avenue, Los Angeles, CA 90033, USA
Virology 324:450-61. 2004..Depletion of cellular cholesterol selectively reduced HCV RNA replication. These findings provide further insights into the mechanism of HCV replication in vivo... - Hepatitis C virus NS5A colocalizes with the core protein on lipid droplets and interacts with apolipoproteinsStephanie T Shi
Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, Los Angeles, California 90033, USA
Virology 292:198-210. 2002.... - HCV core expression in hepatocytes protects against autoimmune liver injury and promotes liver regeneration in miceHiroki Kawamura
Department of Molecular Microbiology, USC/Norris Comprehensive Cancer Center, University of Southern California Keck School of Medicine, Los Angeles, CA 90089-9176, USA
Hepatology 44:936-44. 2006..In conclusion, HCV core inhibits STAT1 and stimulates STAT3 activation, which protects infected hepatocytes from attack by the cell-mediated immune system and promotes their proliferation... - Large hepatitis delta antigen is not a suppressor of hepatitis delta virus RNA synthesis once RNA replication is establishedThomas B Macnaughton
Department of Molecular Microbiology and Immunology, University of Southern California Keck School of Medicine, Los Angeles, California 90033-1054, USA
J Virol 76:9910-9. 2002.... - Toll-like receptor 4 mediates synergism between alcohol and HCV in hepatic oncogenesis involving stem cell marker NanogKeigo Machida
Southern California Research Center for Alcoholic, Liver, and Pancreatic Diseases and Cirrhosis, and Department of Molecular Microbiology, University of Southern California, Keck School of Medicine, 2011 Zonal Avenue, Los Angeles, CA 90033, USA
Proc Natl Acad Sci U S A 106:1548-53. 2009..Taken together, our study demonstrates a TLR4-dependent mechanism of synergistic liver disease by HCV and alcohol and an obligatory role for Nanog, a TLR4 downstream gene, in HCV-induced liver oncogenesis enhanced by alcohol... - SYNCRIP (synaptotagmin-binding, cytoplasmic RNA-interacting protein) is a host factor involved in hepatitis C virus RNA replicationHelene Minyi Liu
Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, Los Angeles, CA 90033, USA
Virology 386:249-56. 2009..These findings indicate that SYNCRIP has dual functions, participating in both RNA replication and translation in HCV life cycle... - Hepatitis C virus causes uncoupling of mitotic checkpoint and chromosomal polyploidy through the Rb pathwayKeigo Machida
Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, Los Angeles, California 90033, USA
J Virol 83:12590-600. 2009..Taken together, these data suggest that HCV infection may inhibit the mitotic checkpoint to induce polyploidy, which likely contributes to neoplastic transformation... - Hepatitis C virus genotype 1b core protein does not exert immunomodulatory effects on virus-induced cellular immunityZhang-Xu Liu
Department of Molecular Microbiology and Immunology, USC/Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, California 90089, USA
J Virol 76:990-7. 2002..It is concluded that the HCV core protein of genotype 1b has no modulatory effects on induction of virus-specific immune responses and may therefore be a suitable component of an HCV vaccine... - Polypyrimidine-tract-binding protein affects transcription but not translation of mouse hepatitis virus RNAKeum S Choi
Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, Los Angeles, California 90033, USA
Virology 303:58-68. 2002.... - The C-terminal transmembrane domain of hepatitis C virus (HCV) RNA polymerase is essential for HCV replication in vivoKi Jeong Lee
Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, Los Angeles, California 90033, USA
J Virol 78:3797-802. 2004..This finding suggests that the C-terminal 21 amino acids not only have a membrane-anchoring function but also may perform additional functions for RNA synthesis in vivo... - Interactions between viral nonstructural proteins and host protein hVAP-33 mediate the formation of hepatitis C virus RNA replication complex on lipid raftLu Gao
Department of Molecular Microbiology and Immunology, University of Southern California Keck School of Medicine, Los Angeles, California 90033, USA
J Virol 78:3480-8. 2004..These results indicate that protein-protein interactions among the various HCV NS proteins and hVAP-33 are important for the formation of HCV replication complex... - Hepatitis delta virus RNA encoding the large delta antigen cannot sustain replication due to rapid accumulation of mutations associated with RNA editingThomas B Macnaughton
Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, California 90033-1054, USA
J Virol 77:12048-56. 2003..They also explain why L-HDAg is not produced early in HDV infection, despite the fact that HDV-L RNA is present in the virion... - Identification of a ribavirin-resistant NS5B mutation of hepatitis C virus during ribavirin monotherapyKung-Chia Young
Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, 2011 Zonal Avenue, Los Angeles, CA 90089-9094, USA
Hepatology 38:869-78. 2003..Furthermore, the selection of an RBV-resistant variant with a single amino acid substitution in NS5B suggested that RBV may directly interact with HCV RNA polymerase, thus interfering with its enzymatic activity... - Establishment of B-cell lymphoma cell lines persistently infected with hepatitis C virus in vivo and in vitro: the apoptotic effects of virus infectionVicky M-H Sung
Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, California 90033, USA
J Virol 77:2134-46. 2003..HCV-infected cell lines show significantly enhanced apoptosis. These B-cell lines provide a reproducible cell culture system for studying the complete replication cycle and biology of HCV infections... - Mutagenic and inhibitory effects of ribavirin on hepatitis C virus RNA polymeraseNam V Vo
Department of Molecular Microbiology and Immunology, University of Southern California School of Medicine, Los Angeles, California 90033-1054, USA
Biochemistry 42:10462-71. 2003..Consequently, the level of RNA synthesis on a ribavirin-containing template is significantly reduced. These findings suggest that ribavirin not only is mutagenic but also interferes with HCV polymerase-mediated RNA synthesis... - Interaction with a ubiquitin-like protein enhances the ubiquitination and degradation of hepatitis C virus RNA-dependent RNA polymeraseLu Gao
Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, California 90033 1054, USA
J Virol 77:4149-59. 2003..Thus, hPLIC1 may be a regulator of HCV RNA replication through interaction with NS5B... 
Hepatitis C virus infection of T cells inhibits proliferation and enhances fas-mediated apoptosis by down-regulating the expression of CD44 splicing variant 6Yasuteru Kondo
Department of Molecular Microbiology and Immunology, University of Southern California Keck School of Medicine, Los Angeles, USA Division of Gastroenterology, Tohoku University, Sendai City
J Infect Dis 199:726-36. 2009..During T cell development and activation, transient expression of CD44 splicing variant 6 (CD44v6) plays a significant role...- Multiple type A/B heterogeneous nuclear ribonucleoproteins (hnRNPs) can replace hnRNP A1 in mouse hepatitis virus RNA synthesisStephanie T Shi
Department of Molecular Microbiology and Immunology and Howard Hughes Medical Institute, University of Southern California Keck School of Medicine, Los Angeles, California 90033, USA
J Virol 77:10584-93. 2003..Our findings demonstrate that the functions of hnRNP A1 in MHV RNA synthesis can be replaced by other closely related hnRNPs, further supporting the roles of cellular proteins in MHV RNA synthesis... - The hepatitis C virus persistence: how to evade the immune system?Nicole Pavio
Department of Molecular Microbiology, University of Southern California, Keck School of Medicine, Los Angeles, CA 90033, USA
J Biosci 28:287-304. 2003..These various strategies used by HCV to counter the immune response of the host are reviewed here. A better understanding of these mechanisms would help design new therapeutic targets... - Hepatitis C virus (HCV)-induced immunoglobulin hypermutation reduces the affinity and neutralizing activities of antibodies against HCV envelope proteinKeigo Machida
Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, 2011 Zonal Avenue, Los Angeles, CA 90033, USA
J Virol 82:6711-20. 2008..These results suggest that HCV infection could cause some anti-HCV-antibody-producing hybridoma B cells to make less-protective antibodies... - Hepatitis C virus infects T cells and affects interferon-gamma signaling in T cell linesYasuteru Kondo
Department of Molecular Microbiology and Immunology, University of Southern California Keck School of Medicine, 2011 Zonal Avenue, Los Angeles, CA 90033, USA
Virology 361:161-73. 2007..In conclusion, HCV could infect and transiently replicate in T cells and that HCV replication suppressed the IFN-gamma/STAT-1/T-bet signaling due to the reduction of STAT-1 and inhibition of its activation (phosphorylation)... - Identification of RNA ligands that bind hepatitis C virus polymerase selectively and inhibit its RNA synthesis from the natural viral RNA templatesNam Viet Vo
Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, Los Angeles, CA 90033-1054, USA
Virology 307:301-16. 2003..These RNA ligands will be useful for further characterization of NS5B-binding properties and, with further modifications, may have potential therapeutic value... - Detection of a novel unglycosylated form of hepatitis C virus E2 envelope protein that is located in the cytosol and interacts with PKRNicole Pavio
Howard Hughes Medical Institute, Keck School of Medicine, University of Southern California, Los Angeles, California 90033, USA
J Virol 76:1265-72. 2002..Thus, an ER protein can exist in the cytosol as an unglycosylated species and impair cellular functions... - Palmitoylation and polymerization of hepatitis C virus NS4B proteinGuann-Yi Yu
Department of Molecular Microbiology and Immunology, University of Southern California Keck School of Medicine, Los Angeles, CA 90033-1054, USA
J Virol 80:6013-23. 2006..The lipid modification and the polymerization activity could be two properties of NS4B important for its induction of the specialized membrane structure involved in viral RNA replication... - Hepatitis C virus IRES-dependent translation is insensitive to an eIF2alpha-independent mechanism of inhibition by interferon in hepatocyte cell linesGennadiy Koev
Howard Hughes Medical Institute, Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, California 90033, USA
Virology 297:195-202. 2002..This may present a new potential mechanism of viral resistance to IFN treatment during the early steps of virus infection... - Hepatitis C virus induces a mutator phenotype: enhanced mutations of immunoglobulin and protooncogenesKeigo Machida
Department of Molecular Microbiology and Immunology, University of Southern California Keck School of Medicine, 2011 Zonal Avenue, Los Angeles, CA 90033, USA
Proc Natl Acad Sci U S A 101:4262-7. 2004..These results indicate that HCV induces a mutator phenotype and may transform cells by a hit-and-run mechanism. This finding provides a mechanism of oncogenesis for an RNA virus... - SYNCRIP, a member of the heterogeneous nuclear ribonucleoprotein family, is involved in mouse hepatitis virus RNA synthesisKeum S Choi
Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, 2011 Zonal Ave, HMR 401, Los Angeles, CA 90033-1054, USA
J Virol 78:13153-62. 2004..These results suggest that SYNCRIP may be directly involved in MHV RNA replication as a positive regulator. This study identified an additional cellular hnRNP as an MHV RNA-binding protein potentially involved in viral RNA synthesis... - Detection and characterization of small and large HDV antigensThomas B Macnaughton
Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, USA
Methods Mol Med 95:99-105. 2004 - Hepatitis delta virus RNA transfection for the cell culture modelThomas B Macnaughton
Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, Los Angeles, USA
Methods Mol Med 96:351-7. 2004 - Hepatitis C virus induces toll-like receptor 4 expression, leading to enhanced production of beta interferon and interleukin-6Keigo Machida
Department of Molecular Microbiology and Immunology, USC Keck School of Medicine, 2011 Zonal Avenue, Los Angeles, CA 90033, USA
J Virol 80:866-74. 2006..In conclusion, HCV infection directly induces TLR4 expression and thereby activates B cells, which may contribute to the host's innate immune responses... - Polypyrimidine-tract-binding protein is a component of the HCV RNA replication complex and necessary for RNA synthesisHideki Aizaki
Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, 2011 Zonal Ave, HMR-503, Los Angeles, CA 90033, USA
J Biomed Sci 13:469-80. 2006..These studies together indicated that PTB is a part of the HCV RNA replication complex and participates in viral RNA synthesis. Thus, PTB has dual functions in HCV life cycle, including translation and RNA replication... - Transcription of subgenomic mRNA of hepatitis delta virus requires a modified hepatitis delta antigen that is distinct from antigenomic RNA synthesisChung Hsin Tseng
Institute of Molecular Biology, Academia Sinica, Taipei 115, Taiwan
J Virol 82:9409-16. 2008..We propose that acetylation and deacetylation of HDAg may provide a molecular switch for the synthesis of the different HDV RNA species... - Association of hepatitis C virus replication complexes with microtubules and actin filaments is dependent on the interaction of NS3 and NS5AChao Kuen Lai
Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
J Virol 82:8838-48. 2008.... - [Hepatitis C virus replication associated with lipid rafts]Hideki Aizaki
Department of Virology II, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan
Seikagaku 78:321-6. 2006 - Redox modulation of the hepatitis C virus replication complex is calcium dependentJinah Choi
School of Natural Sciences, University of California at Merced, CA 95344, USA
Free Radic Biol Med 41:1488-98. 2006..Effects on the infectivity and the morphogenesis of HCV remain to be determined. These findings suggest possible regulatory roles for redox and calcium signaling during viral infections...