EBNA2 amino acids 3 to 30 are required for induction of LMP-1 and immortalization maintenance.
Epstein-Barr virus (EBV) nuclear antigen 2 (EBNA2), a direct transcriptional activator of viral and cellular genes, is required for EBV-induced B-cell transformation. The functional role of conserved regions within the amino terminus of the protein preceding the poly-proline region has yet to be fully characterized. Thus, we tested whether the EBNA2 amino-terminal 30 amino acid residues, containing evolutionarily conserved region 1, are required for stimulating viral and cellular gene expression necessary for B-cell transformation in a viral transcomplementation assay. We found that these residues are required for its ability to induce LMP-1 expression in lymphoblastoid cell lines (LCLs), to stimulate LMP-1 promoter reporter plasmids in transient-cotransfection assays, and to rescue LCL growth following inactivation of endogenous wild-type EBNA2 protein. Deletion of amino acid residues 3 to 30 also impaired its ability to self-associate in coimmunoprecipitation assays. These data indicate that EBNA2 residues 3 to 30 comprise an essential domain required for induction of LMP-1 expression and, consequently, for maintenance of the immortalized phenotype of LCLs. The ability to self-associate into dimers or multimers conferred by this domain may be an important mechanism for these effects.
Gordadze
Alexey V
AV
Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas 77030, USA.
Onunwor
Chisaroka W
CW
Peng
RongSheng
R
Poston
David
D
Kremmer
Elisabeth
E
Ling
Paul D
PD
D048868:Adaptor Proteins, Signal Transducing; D000595:Amino Acid Sequence; D001402:B-Lymphocytes / Q000166:cytology / Q000821:virology; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D002051:Burkitt Lymphoma / Q000235:genetics / Q000503:physiopathology / Q000821:virology; D002352:Carrier Proteins / Q000096:biosynthesis* / Q000235:genetics; D002460:Cell Line; D045744:Cell Line, Tumor; D002472:Cell Transformation, Viral / Q000235:genetics / Q000502:physiology*; D003598:Cytoskeletal Proteins; D004279:DNA, Viral / Q000235:genetics; D004268:DNA-Binding Proteins / Q000378:metabolism; D019309:Epstein-Barr Virus Nuclear Antigens / Q000737:chemistry* / Q000235:genetics / Q000502:physiology*; D015870:Gene Expression; D016259:Genes, myc; D004854:Herpesvirus 4, Human / Q000235:genetics / Q000502:physiology; D006801:Humans; D051819:Immunoglobulin J Recombination Signal Sequence-Binding Protein; D047908:Intracellular Signaling Peptides and Proteins; D060588:LIM Domain Proteins; D009687:Nuclear Proteins / Q000378:metabolism; D011401:Promoter Regions, Genetic; D014162:Transfection; D014764:Viral Proteins
D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; D003598:Cytoskeletal Proteins; D004279:DNA, Viral; D004268:DNA-Binding Proteins; C402641:EBNA-2 protein, Human herpesvirus 4; D019309:Epstein-Barr Virus Nuclear Antigens; D051819:Immunoglobulin J Recombination Signal Sequence-Binding Protein; D047908:Intracellular Signaling Peptides and Proteins; D060588:LIM Domain Proteins; D009687:Nuclear Proteins; C484380:PDLIM7 protein, human; C497570:RBPJ protein, human; D014764:Viral Proteins