DNA structure and flexibility in the sequence-specific binding of papillomavirus E2 proteins

摘要: The papillomavirus E2 proteins are transcriptional regulators that bind to a consensus DNA sequence ACCG NNNN CGGT. Multiple copies of this binding site found in the viral genomes. affinities naturally occurring sites for predominantly dependent upon spacer. hierarchies among present genomes result differential occupancy during life-cycle. In turn, regulates transcription from promoters, including those oncogenes E6 and E7. Structural biochemical studies have shown bend which they specifically bind. Atomic resolution structures complexes bovine strain 1 (BPV-1) protein show does not contact spacer DNA. A direct comparison DNA-binding domains BPV-1 human 16 (HPV-16) series as function their central and/or presence nick or gap one strand is presented paper. domain only moderately sensitive nature spacer; less than several fold differences affinity were observed when was varied introduced. contrast, HPV-16 binds containing A:T-rich spacers with significantly increased affinity. introduction into these high sequences very detrimental while comparable nicks gaps small effects low sequences. These results suggest recognizes structure mechanism DNA-sequence specific homologous different.