2005 Fiscal Year Final Research Report Summary
The role of Epstein-Barr virus nuclear protein EBNA3A in B lymphocyte growth transformation
Project/Area Number |
16590380
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Virology
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Research Institution | Hokkaido University |
Principal Investigator |
MARUO Seiji Hokkaido University, Institute for Genetic Medicine, Associate Professor, 遺伝子病制御研究所, 助教授 (70292018)
|
Project Period (FY) |
2004 – 2005
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Keywords | EBV / Growth transformation / EBNA3A / RBP-Jκ |
Research Abstract |
Epstein-Barr virus (EBV) infection converts primary human B lymphocytes in vitro into continuously proliferating lymphoblastoid cell lines (LCLs). Reverse genetic experiments showed that EBV nuclear protein EBNA3A is essential for EBV-mediated growth transformation. To investigate how EBNA3A contributes to LCL growth, we established LCLs that express a conditionally active EBNA3A. Conditional EBNA3A LCLs ceased growing after EBNA3A inactivation. EBNA3A associates with the sequence-specific DNA binding protein RBP-Jκ. A series of EBNA3A deletion mutants were constructed and tested for the ability to associate with RBP-Jκ or the ability to repress RBP-Jκ-dependent transcription. We identified EBNA3A amino acid (aa) 170-240 is essential for the association with RBP-Jκ. EBNA3A aa 170-240, and EBNA3A aa 300-386 are required for the repression of RBP-Jκ-dependent transcription. Importantly, transcomplementation assay using conditional EBNA3A LCLs indicated that EBNA3A aa 170-240, and 300-386 are essential for LCL growth maintenance. The EBNA3A triple point mutant within the core RBP-Jκ binding domain that is deficient in repression was also null mutation for LCL growth. Thus, EBNA3A transcriptional regulation through RBP-Jκ is critical for LCL growth maintenance. We extracted RNAs from EBNA3A-active LCLs and EBNA3A-inactive LCLs, and performed MicroArray Analysis. We identified 13 EBNA3A-induced cellular genes and 41 EBNA3A-repressed cellular genes.
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Research Products
(3 results)