Physical interaction of Epstein-Barr virus (EBV) nuclear antigen leader protein (EBNA-LP) with human oestrogen-related receptor 1 (hERR1): hERR1 interacts with a conserved domain of EBNA-LP that is critical for EBV-induced B-cell immortalization.
Epstein-Barr virus (EBV) nuclear antigen leader protein (EBNA-LP) consists of W1W2 repeats and a unique C-terminal Y1Y2 domain and plays a critical role in EBV-induced transformation. To identify the cellular proteins associating with EBNA-LP, we performed a yeast two-hybrid screen using EBNA-LP cDNA containing a single W1W2 domain as bait and an EBV-transformed human peripheral blood lymphocyte cDNA library as the source of cellular genes. Our results were as follows. (i) A cDNA in the positive yeast colony was found to encode a cellular protein, human oestrogen-related receptor 1 (hERR1), which is a constitutive transcriptional activator of the various types of oestrogen response elements. (ii) A purified chimeric protein consisting of glutathione S-transferase (GST) fused to hERR1 specifically formed complexes with EBNA-LPs containing one (EBNA-LPR1), two (EBNA-LPR2) or four W1W2 repeats (EBNA-LPR4) transiently expressed in COS-7 cells. Reciprocally, GST fused to EBNA-LPR1 or EBNA-LPR2 pulled down hERR1 transiently expressed in COS-7 cells. (iii) Mutational analyses of EBNA-LP revealed that the Y2 domain of EBNA-LP is responsible for the interaction with hERR1 and two leucines in the Y2 domain (Leu-78 and -82), which are conserved among a subset of primate gammaherpesviruses, are interactive sites for hERR1. So far, it has been reported that the only domain of EBNA-LP critical for EBV-induced transformation is the Y1Y2 domain. Potential roles of hERR1 in EBV-induced transformation are discussed.
Igarashi
Mie
M
Department of Microbiology, Tokyo Medical University, 6-1-1, Shinjuku, Shinjuku-ku, Tokyo 160-8402, Japan.|Department of Tumor Virology, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
Kawaguchi
Yasushi
Y
Department of Tumor Virology, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
Hirai
Kanji
K
Department of Tumor Virology, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
Mizuno
Fumio
F
Department of Microbiology, Tokyo Medical University, 6-1-1, Shinjuku, Shinjuku-ku, Tokyo 160-8402, Japan.
D000595:Amino Acid Sequence; D000818:Animals; D001402:B-Lymphocytes / Q000821:virology; D019556:COS Cells; D002472:Cell Transformation, Viral; D017124:Conserved Sequence; D015723:Gene Library; D005982:Glutathione Transferase / Q000235:genetics / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D008969:Molecular Sequence Data; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D020798:Two-Hybrid System Techniques; D014764:Viral Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D000097983:ERRalpha Estrogen-Related Receptor
D005982:Glutathione Transferase; D018160:Receptors, Cytoplasmic and Nuclear; D011960:Receptors, Estrogen; D011993:Recombinant Fusion Proteins; D014764:Viral Proteins; D000097983:ERRalpha Estrogen-Related Receptor; C402640:EBNA-LP protein, Human herpesvirus 4