Transcription factor human Skn-1a enhances replication of human papillomavirus DNA through the direct binding to two sites near the viral replication origin.
Human papillomavirus type 16 (HPV16) DNA replication, which requires two viral proteins E1 and E2, occurs only in the differentiating epithelium. Besides the general factors necessary for cellular DNA synthesis, other unidentified cellular factors are assumed to be involved in the regulation of HPV DNA replication. In the present study, we found that the POU-domain transcription factor human Skn-1a, which induces the terminal differentiation of keratinocytes and activates the HPV16 late promoter, enhanced the transient replication of a plasmid containing the HPV16 replication origin in HEK293 cells when co-transfected with a plasmid expressing E1 and E2. An electrophoretic mobility shift assay with a bacterially expressed human Skn-1a or an extract of HeLa cells over-expressing human Skn-1a revealed the presence of two human Skn-1a binding sites that are distinct from the known three sites, near the replication origin. A chromatin immunoprecipitation analysis showed that human Skn-1a bound to these sites in cells. Nucleotide substitutions in the sites abolished the binding of human Skn-1a and the human Skn-1a-mediated replication enhancement. The data strongly suggest that, through the binding to the two sites, human Skn-1a enhances HPV DNA replication.
Kukimoto
Iwao
I
Center for Pathogen Genomics, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo, Japan. ikuki@nih.go.jp
Mori
Seiichiro
S
Sato
Hidetaka
H
Takeuchi
Takamasa
T
Kanda
Tadahito
T
D001665:Binding Sites; D002460:Cell Line; D004261:DNA Replication; D004279:DNA, Viral / Q000096:biosynthesis*; D016679:Genome, Viral; D052162:Human papillomavirus 16 / Q000235:genetics* / Q000502:physiology; D006801:Humans; D009154:Mutation; D050810:Octamer Transcription Factors / Q000737:chemistry / Q000378:metabolism*; D010957:Plasmids / Q000235:genetics; D017434:Protein Structure, Tertiary; D018741:Replication Origin; D014779:Virus Replication
D004279:DNA, Viral; D050810:Octamer Transcription Factors; C484169:POU2F3 protein, human