title: Epstein-Barr virus nuclear protein 3C binds to the N-terminal (NTD) and beta trefoil domains (BTD) of RBP/CSL; only the NTD interaction is essential for lymphoblastoid cell growth.
abstract: Association of EBV nuclear proteins EBNA2, EBNA3A and EBNA3C with RBP/CSL, is essential for lymphoblastoid cell line (LCL) proliferation. Conserved residues in the EBNA3 homology domain, required for RBP/CSL interaction, lack the WΦP motif that mediates EBNA2 and Notch binding to the RBP/CSL beta-trefoil domain (BTD). We map RBP/CSL interacting residues within EBNA3A(aa128-204) and EBNA3C(aa211-233). The EBNA3A results are consistent with an earlier report (aa125-222), but the EBNA3C domain is unexpectedly small and includes a "WTP" sequence. This EBNA3C WTP motif confers RBP/CSL binding in vitro, in yeast, and in mammalian cells. Further, an EBNA3C WTP→STP(W227S) mutation impaired BTD binding whereas EBNA3 homology domain mutations disrupted RBP/CSL N-terminal domain (NTD) binding. WTP was not essential for EBNA3C repression of EBNA2 in reporter assays or for maintenance of LCL growth. Our results indicate that EBNA3 proteins interact with multiple RBP/CSL domains, but only NTD interactions are required for LCL growth.
authors: Department of Medicine, Channing Laboratory, Brigham and Women's Hospital, Harvard Medical School, 181 Longwood Avenue, Boston, MA 02115, USA.
authors: Michael A
authors: MA
authors: Calderwood
authors: Sungwook
authors: S
authors: Lee
authors: Amy M
authors: AM
authors: Holthaus
authors: Stephen C
authors: SC
authors: Blacklow
authors: Elliott
authors: E
authors: Kieff
authors: Eric
authors: E
authors: Johannsen
mesh_terms: D000956:Antigens, Viral / Q000378:metabolism*; D002460:Cell Line; D019309:Epstein-Barr Virus Nuclear Antigens / Q000378:metabolism*; D017930:Genes, Reporter; D004854:Herpesvirus 4, Human / Q000472:pathogenicity*; D054884:Host-Pathogen Interactions; D006801:Humans; D051819:Immunoglobulin J Recombination Signal Sequence-Binding Protein / Q000378:metabolism*; D047468:Immunoprecipitation; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D025941:Protein Interaction Mapping; D020798:Two-Hybrid System Techniques
chemical_list: D000956:Antigens, Viral; C508151:EBNA-3A antigen; C498774:EBNA-3C, epstein-barr virus; D019309:Epstein-Barr Virus Nuclear Antigens; D051819:Immunoglobulin J Recombination Signal Sequence-Binding Protein; C497570:RBPJ protein, human; D008156:Luciferases