Heat shock factor 1 upregulates transcription of Epstein-Barr Virus nuclear antigen 1 by binding to a heat shock element within the BamHI-Q promoter.
Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA1) is essential for maintenance of the episome and establishment of latency. In this study, we observed that heat treatment effectively induced EBNA1 transcription in EBV-transformed B95-8 and human LCL cell lines. Although Cp is considered as the sole promoter used for the expression of EBNA1 transcripts in the lymphoblastoid cell lines, the RT-PCR results showed that the EBNA1 transcripts induced by heat treatment arise from Qp-initiated transcripts. Using bioinformatics, a high affinity and functional heat shock factor 1 (HSF1)-binding element within the -17/+4 oligonucleotide of the Qp was found, and was determined by electrophoretic mobility shift assay and chromatin immunoprecipitation assay. Moreover, heat shock and exogenous HSF1 expression induced Qp activity in reporter assays. Further, RNA interference-mediated HSF1 gene silencing attenuated heat-induced EBNA1 expression in B95-8 cells. These results provide evidence that EBNA1 is a new target for the transcription factor HSF1.
The State Key Laboratory of Oncology in South China, Cancer Center, Sun Yat-Sen University, Guangzhou, China.
Feng-Wei
FW
Wang
Xian-Rui
XR
Wu
Wen-Ju
WJ
Liu
Yi-Ji
YJ
Liao
Sheng
S
Lin
Yong-Sheng
YS
Zong
Mu-Sheng
MS
Zeng
Yi-Xin
YX
Zeng
Shi-Juan
SJ
Mai
Dan
D
Xie
D000818:Animals; D001402:B-Lymphocytes / Q000821:virology; D002144:Callithrix; D002461:Cell Line, Transformed; D047369:Chromatin Immunoprecipitation; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D015245:Deoxyribonuclease BamHI; D024202:Electrophoretic Mobility Shift Assay; D019309:Epstein-Barr Virus Nuclear Antigens / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D015967:Gene Expression Regulation, Viral; D000076249:Heat Shock Transcription Factors; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D018869:Heat-Shock Response; D004854:Herpesvirus 4, Human / Q000235:genetics / Q000378:metabolism; D006801:Humans; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000096:biosynthesis; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic; D015854:Up-Regulation; D017735:Virus Latency / Q000235:genetics
D004268:DNA-Binding Proteins; D019309:Epstein-Barr Virus Nuclear Antigens; C000619706:HSF1 protein, human; D000076249:Heat Shock Transcription Factors; D006360:Heat-Shock Proteins; D012333:RNA, Messenger; D014157:Transcription Factors; D015245:Deoxyribonuclease BamHI