P32/TAP, a cellular protein that interacts with EBNA-1 of Epstein-Barr virus

被引:141
作者
Wang, YL
Finan, JE
Middeldorp, JM
Hayward, SD
机构
[1] JOHNS HOPKINS UNIV, SCH MED, DEPT PHARMACOL & MOL SCI, MOL VIROL LAB, BALTIMORE, MD 21205 USA
[2] ORGANON TEKN, NL-5281 RM BOXTEL, NETHERLANDS
关键词
D O I
10.1006/viro.1997.8739
中图分类号
Q93 [微生物学];
学科分类号
071005 ; 100705 ;
摘要
The Epstein-Barr virus (EBV) EBNA-1 protein has a central role in the maintenance of a latent EBV infection and is the only virus-encoded protein expressed in all EBV-associated tumors. EBNA-1 is required for replication of the episomal form of the latent viral genome and transactivates the latency C and LMP-1 promoters. The mechanisms by which EBNA-1 performs these functions are not known. Here we describe the cloning, expression, and characterization of a cellular protein, P32/TAP, which strongly interacts with EBNA-1. We show that P32/TAP is expressed at high levels in Raji cells and is synthesized as a proprotein of 282 amino acids (aa) that is posttranslationally processed by a two-step cleavage process to yield a mature protein of 209 aa. It has been previously reported that P32/TAP is expressed on the cell surface. Our transient expression assays detected full-length P32/TAP (1-282 aa) in the cytoplasm while mature P32/TAP protein localized to the nucleus. Three lines of evidence support P32/TAP interaction with EBNA-1. First, in the yeast two-hybrid system we mapped two interactive N-terminal regions of EBNA-1, aa 40-60 and aa 325-376, each of which contains arginine-glycine repeats, These regions interact with the C-terminal half of P32/TAP. Second, the full-length cytoplasmic P32/TAP protein can translocate nuclear EBNA-1 into the cytoplasm. Third, P32/TAP co-immunoprecipitated with EBNA-1, We have confirmed that a Gal4 fusion protein containing the C-terminal region of P32/TAP (aa 244-282) transactivates expression from a reporter containing upstream Gal4-binding sites. Deletion of the P32/TAP interactive regions of EBNA-1 severely diminished EBNA-1 transactivation of FRTKCAT in transient expression assays. Our data suggest that interaction with P32/TAP may contribute to EBNA-1-mediated transactivation. (C) 1997 Academic Press.
引用
收藏
页码:18 / 29
页数:12
相关论文
共 70 条
[1]   DEFINITION OF THE SEQUENCE REQUIREMENTS FOR BINDING OF THE EBNA-1 PROTEIN TO ITS PALINDROMIC TARGET SITES IN EPSTEIN-BARR-VIRUS DNA [J].
AMBINDER, RF ;
SHAH, WA ;
RAWLINS, DR ;
HAYWARD, GS ;
HAYWARD, SD .
JOURNAL OF VIROLOGY, 1990, 64 (05) :2369-2379
[2]   FUNCTIONAL DOMAINS OF EPSTEIN-BARR-VIRUS NUCLEAR ANTIGEN EBNA-1 [J].
AMBINDER, RF ;
MULLEN, M ;
CHANG, YN ;
HAYWARD, GS ;
HAYWARD, SD .
JOURNAL OF VIROLOGY, 1991, 65 (03) :1466-1478
[3]   NOTCH SIGNALING [J].
ARTAVANISTSAKONAS, S ;
MATSUNO, K ;
FORTINI, ME .
SCIENCE, 1995, 268 (5208) :225-232
[4]   Crystal structure of the DNA-Binding domain of the Epstein-Barr virus origin-binding protein, EBNA1, bound to DNA [J].
Bochkarev, A ;
Barwell, JA ;
Pfuetzner, RA ;
Bochkareva, E ;
Frappier, L ;
Edwards, AM .
CELL, 1996, 84 (05) :791-800
[5]   REGULATION OF THE YEAST HO GENE [J].
BREEDEN, L ;
NASMYTH, K .
COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY, 1985, 50 :643-650
[6]  
BRUCKNER RC, 1991, J BIOL CHEM, V266, P2669
[7]   Open reading frame P - A herpes simplex virus gene repressed during productive infection encodes a protein that binds a splicing factor and reduces synthesis of viral proteins made from spliced mRNA [J].
Bruni, R ;
Roizman, B .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1996, 93 (19) :10423-10427
[8]   HIGH-EFFICIENCY TRANSFORMATION OF MAMMALIAN-CELLS BY PLASMID DNA [J].
CHEN, C ;
OKAYAMA, H .
MOLECULAR AND CELLULAR BIOLOGY, 1987, 7 (08) :2745-2752
[9]   DELINEATION OF A 16-AMINO-ACID-SEQUENCE THAT FORMS A CORE DNA RECOGNITION MOTIF IN THE EPSTEIN-BARR-VIRUS EBNA-1 PROTEIN [J].
CHEN, MR ;
ZONG, JC ;
HAYWARD, SD .
VIROLOGY, 1994, 205 (02) :486-495
[10]   SEPARATION OF THE COMPLEX DNA-BINDING DOMAIN OF EBNA-1 INTO DNA RECOGNITION AND DIMERIZATION SUBDOMAINS OF NOVEL STRUCTURE [J].
CHEN, MR ;
MIDDELDORP, JM ;
HAYWARD, SD .
JOURNAL OF VIROLOGY, 1993, 67 (08) :4875-4885