TAF-like functions of human cytomegalovirus immediate-early proteins

被引:89
作者
Lukac, DM
Harel, NY
Tanese, N
Alwine, JC
机构
[1] UNIV PENN,SCH MED,DEPT MICROBIOL,PHILADELPHIA,PA 19104
[2] UNIV PENN,SCH MED,GRAD GRP MOL BIOL,PHILADELPHIA,PA 19104
[3] NYU,MED CTR,DEPT MICROBIOL,NEW YORK,NY 10016
[4] NYU,MED CTR,KAPLAN CANC CTR,NEW YORK,NY 10016
关键词
D O I
10.1128/JVI.71.10.7227-7239.1997
中图分类号
Q93 [微生物学];
学科分类号
071005 ; 100705 ;
摘要
The human cytomegalovirus (HCMV) major immediate-early (IE) proteins IEP86 (IE2(579aa)) and IEP72 (IE1(491aa)) can transcriptionally activate a variety of simple promoters containing a TATA element and one upstream transcription factor binding site, In our previous studies, transcriptional activation was shown to correlate with IEP86 binding to both the TATA-box binding protein (TBP) and the transcription factor bound upstream, IEP72 often synergistically affects the activation by IEP86, although it has not previously been shown to directly interact in vitro with IEP86, TBP, or transcription factors (e.g., Spl and Tef-1) bound by IEP86. We report biochemical and genetic evidence suggesting that the major IE proteins may perform a function similar to that of the TBP-associated factors (TAFs) which make up TFIID. Consistent with this model, we found that the major IE proteins interact with a number of TAFs, In vitro, IEP86 bound with drosophila TAF(II)110 (dTAF(II)110) and human TAF(II)130 (hTAF(II)130), while IEP72 bound dTAF(II)40, dTAF(II)110, and hTAF,130, Regions on major IE proteins which mediate binding have been defined. In addition, our data indicate that both IEP72 and IEP86 can bind simultaneously to hTAF(II)130, suggesting that this TAF may provide bridging interactions between the two proteins for transcriptional activation and synergy, In agreement, a transcriptional activation mutant of IEP72 is unable to participate in bridging. Confirmation that these in vitro interactions were relevant was provided by data showing that both IEP72 and IEP86 copurify with TFIID and coimmunoprecipitate with purified TFIID derived from infected cell nuclei, To further support a TAF-like function of the IE proteins, we have found that the IE proteins expressed from the intact major IE gene, and to a lesser extent IEP86 alone, can rescue the temperature-sensitive (ts) transcriptional defect in TAF(II)250 in the BHK-21 cell line ts13, Analyses of mutations in the major IE region show that IEP86 is essential for rescue and that IEP72 augments its effect, and that mutations which affect TAF interactions are debilitated in rescue. Our data, showing that the IE proteins can bind with TFIID and rescue a ts transcriptional defect in TAF(II)250, support the model that the IE proteins perform a TAF-like function as components of TFIID.
引用
收藏
页码:7227 / 7239
页数:13
相关论文
共 91 条
[2]   IDENTIFICATION OF BINDING-SITES FOR THE 86-KILODALTON IE2 PROTEIN OF HUMAN CYTOMEGALOVIRUS WITHIN AN IE2-RESPONSIVE VIRAL EARLY PROMOTER [J].
ARLT, H ;
LANG, D ;
GEBERT, S ;
STAMMINGER, T .
JOURNAL OF VIROLOGY, 1994, 68 (07) :4117-4125
[3]   SUPPRESSION OF HUMAN COLORECTAL-CARCINOMA CELL-GROWTH BY WILD-TYPE-P53 [J].
BAKER, SJ ;
MARKOWITZ, S ;
FEARON, ER ;
WILLSON, JKV ;
VOGELSTEIN, B .
SCIENCE, 1990, 249 (4971) :912-915
[4]   AN ISOFORM VARIANT OF THE CYTOMEGALOVIRUS IMMEDIATE EARLY AUTO REPRESSOR FUNCTIONS AS A TRANSCRIPTIONAL ACTIVATOR [J].
BARACCHINI, E ;
GLEZER, E ;
FISH, K ;
STENBERG, RM ;
NELSON, JA ;
GHAZAL, P .
VIROLOGY, 1992, 188 (02) :518-529
[5]   CYTOMEGALOVIRUS ACTIVATES TRANSCRIPTION DIRECTED BY THE LONG TERMINAL REPEAT OF HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 [J].
BARRY, PA ;
PRATTLOWE, E ;
PETERLIN, BM ;
LUCIW, PA .
JOURNAL OF VIROLOGY, 1990, 64 (06) :2932-2940
[6]   SEQUENCE REQUIREMENTS FOR ACTIVATION OF THE HIV-1 LTR BY HUMAN CYTOMEGALOVIRUS [J].
BIEGALKE, BJ ;
GEBALLE, AP .
VIROLOGY, 1991, 183 (01) :381-385
[7]   FUNCTIONAL INTERACTION OF ADENOVIRUS-E1A WITH HOLO-TFIID [J].
BOYER, TG ;
BERK, AJ .
GENES & DEVELOPMENT, 1993, 7 (09) :1810-1823
[8]  
BURNS LJ, 1993, BLOOD, V81, P1558
[9]   Human cytomegalovirus immediate-early 2 (IE2) protein can transactivate the human hsp70 promoter by alleviation of Dr1-mediated repression [J].
Caswell, R ;
Bryant, L ;
Sinclair, J .
JOURNAL OF VIROLOGY, 1996, 70 (06) :4028-4037
[10]   THE HUMAN CYTOMEGALOVIRUS-86K IMMEDIATE-EARLY (IE) 2-PROTEIN REQUIRES THE BASIC REGION OF THE TATA-BOX BINDING-PROTEIN (TBP) FOR BINDING, AND INTERACTS WITH TBP AND TRANSCRIPTION FACTOR TFIIB VIA REGIONS OF IE2 REQUIRED FOR TRANSCRIPTIONAL REGULATION [J].
CASWELL, R ;
HAGEMEIER, C ;
CHIOU, CJ ;
HAYWARD, G ;
KOUZARIDES, T ;
SINCLAIR, J .
JOURNAL OF GENERAL VIROLOGY, 1993, 74 :2691-2698