Identification of cis-regulatory elements in the upstream regulatory region of human papillomavirus type 59

Abstract

Human papillomavirus type 59 (HPV-59) was cloned from a vulvar intraepithelial neoplasia and the complete nucleotide sequence was determined. This virus is closely related to HPV-18 and -39 (600/0 homology in nucleotide sequence) and is grouped with the genital HPV types. In the present paper, we demonstrate that the HPV-59 E2 transactivator represses its E6 promoter-mediated transcription. We have also analyzed cis-regulatory elements in the upstream regulatory region (URR) of HPV-59 using chloramphenicol acetyl transferase assays as well as electrophoresis mobility shift assays (EMSA). The results allow for a subdivision of the HPV-59 URR into three regions of activity: distal (nt 7149-7493), central (nt 7493-7742), and proximal (nt 7742-7748). In particular, the 250 bp (nt 7493-7742) of the central region plays an important role as a constitutive enhancer element for the maximal transcription of the E6 promoter. Our results suggest that the transcription factors AP1, Oct1, SP1 and unidentified factors bind to the HPV-59 E6 promoter region, whereas NF1, GRE and TFIID fail to bind despite the presence of putative binding sites in the DNA sequence. (C) 1997 Elsevier Science B.V.