Epstein-Barr virus nuclear antigen 2 induces FcRH5 expression through CBF1.
Fc-receptor homolog 5 (FcRH5) is a recently identified B-cell membrane protein of unknown function. In Burkitt lymphoma cell lines with chromosome 1q21 abnormalities, FcRH5 expression is deregulated, implicating FcRH5 in lymphomagenesis. Epstein-Barr virus infects and immortalizes B cells, and is implicated in the etiology of several tumors of B-cell origin. Overexpression of genes located on 1q21-25 has been proposed as a surrogate for Epstein-Barr virus in Burkitt lymphoma. We now report that Epstein-Barr virus nuclear antigen 2 (EBNA2) markedly induces the expression of the FcRH5 gene, encoded on chromosome 1q21. Induction occurred in the absence of other viral proteins and did not require de novo protein synthesis. EBNA2 lacks a DNA-binding domain and can target responsive genes through the host DNA binding protein CBF1. We show that induction of FcRH5 by EBNA2 is strictly CBF1 dependent, as it was abolished in CBF1-deficient cells. Accordingly, EBNA2 targeted CBF1 binding sites present in the FcRH5 promoter in vivo, as detected by chromatin immunoprecipitation. These results identify FcRH5 as a novel, direct target of EBNA2 that may contribute to the development of Epstein-Barr virus-associated tumors.
Mohan
Joanne
J
Division of Monoclonal Antibodies, Center for Drug Evaluation and Research, Food and Drug Administration, Rockville, MD 20857, USA.
Dement-Brown
Jessica
J
Maier
Sabine
S
Ise
Tomoko
T
Kempkes
Bettina
B
Tolnay
Mate
M
D001402:B-Lymphocytes / Q000276:immunology*; D001665:Binding Sites; D002460:Cell Line; D002878:Chromosomes, Human, Pair 1; D019309:Epstein-Barr Virus Nuclear Antigens / Q000502:physiology*; D005786:Gene Expression Regulation / Q000276:immunology*; D006801:Humans; D051819:Immunoglobulin J Recombination Signal Sequence-Binding Protein; D011401:Promoter Regions, Genetic; D011956:Receptors, Cell Surface / Q000235:genetics*; D011961:Receptors, Fc / Q000235:genetics*; D014764:Viral Proteins
C402641:EBNA-2 protein, Human herpesvirus 4; D019309:Epstein-Barr Virus Nuclear Antigens; C432367:FCRL5 protein, human; D051819:Immunoglobulin J Recombination Signal Sequence-Binding Protein; C497570:RBPJ protein, human; D011956:Receptors, Cell Surface; D011961:Receptors, Fc; D014764:Viral Proteins