Adeno-associated virus Rep78 binds to E2-responsive element 1 of bovine papillomavirus type 1.
Adeno-associated virus type-2 (AAV-2) is a helper-dependent parvovirus that has been implicated in the inhibition of replication and oncogenic transformation of bovine papillomavirus type-1 (BPV-1) and other transforming DNA viruses. Previous studies have suggested that the Rep78 protein of AAV-2 is a key player mediating this effect. In this report we have analyzed the effect of AAV-2 Rep78 protein on the regulation of gene expression of a reporter gene under the control of the long control region (LCR) of BPV-1. Our results show that Rep78 is capable of down-regulating the promoter activity of the LCR in vivo in tissue culture cells. Inhibition of LCR activity in vivo suggested the need for Rep78 to bind to a region of the LCR promoter spanning the E2-responsive elements of BPV-1. This observation was further confirmed in vitro with gel shift assays showing specific binding of Rep78 to DNA oligonucleotides containing E2-responsive element 1 (E2RE1) sequences of BPV-1 LCR. Our results expand the understanding of the mechanism of trans-regulation mediated by Rep78 and involving this protein and DNA sequences with complex secondary structure.
Chon
S K
SK
College of Veterinary Medicine, Chonbuk National University, Chonju, Korea. schon@unlinfo2.un1.edu
Rim
B M
BM
Im
D S
DS
D000818:Animals; D001483:Base Sequence; D052688:Bovine papillomavirus 1 / Q000235:genetics* / Q000378:metabolism*; D002417:Cattle; D002461:Cell Line, Transformed; D004268:DNA-Binding Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D000229:Dependovirus / Q000235:genetics / Q000378:metabolism*; D015536:Down-Regulation / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015967:Gene Expression Regulation, Viral; D006801:Humans; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics; D020218:Response Elements; D013379:Substrate Specificity; D020079:Terminal Repeat Sequences; D014764:Viral Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*
D004268:DNA-Binding Proteins; C051550:E2 protein, Bovine papillomavirus; D011994:Recombinant Proteins; D014764:Viral Proteins; C068734:rep proteins, Adeno-associated virus 2