Analysis of transcriptional regulatory sequences in the human endogenous retrovirus W long terminal repeat.
The U3 region of the human endogenous retrovirus W long terminal repeat (HERV-W LTR) contains several putative regulatory sequences that might not only regulate transcription of viral genes but also influence the expression of neighbouring cellular genes. In this study, we analysed the U3 region in detail in order to understand the transcriptional regulatory mechanism of HERV-W. Two transcription factor (TF) binding sites for Oct-1 and C/EBP were important as a silencer and an enhancer, respectively, for transcriptional regulation. Furthermore, it was possible to divide the HERV-W LTR isolates into two groups depending on their promoter strength, which might be determined by the integrity of the two TF binding sites. However, neither the Oct-1 binding site nor the CAAT-box was required for the cell type-specific activity of the HERV-W LTR. Instead, the 3' terminus of U3 from 191 to 260, which includes a TATA box, was sufficient for specificity, suggesting that the efficiency of assembly of basic transcription machinery at the TATA box of HERV-W LTR might determine the cell type specificity.
Lee
Woo Jung
WJ
Department of Microbiology, College of Natural Sciences, Pusan National University, Pusan 609-735, South Korea.
Kwun
Hyun Jin
HJ
Department of Microbiology, College of Natural Sciences, Pusan National University, Pusan 609-735, South Korea.
Jang
Kyung Lib
KL
Department of Microbiology, College of Natural Sciences, Pusan National University, Pusan 609-735, South Korea.
D001665:Binding Sites; D002460:Cell Line; D004268:DNA-Binding Proteins / Q000378:metabolism; D020077:Endogenous Retroviruses / Q000235:genetics*; D015967:Gene Expression Regulation, Viral; D006367:HeLa Cells; D051863:Host Cell Factor C1; D006801:Humans; D050811:Octamer Transcription Factor-1; D011401:Promoter Regions, Genetic; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics*; D020079:Terminal Repeat Sequences / Q000235:genetics*; D014157:Transcription Factors / Q000378:metabolism; D014158:Transcription, Genetic
D004268:DNA-Binding Proteins; C497692:HCFC1 protein, human; D051863:Host Cell Factor C1; D050811:Octamer Transcription Factor-1; C494165:POU2F1 protein, human; D014157:Transcription Factors