Transcriptional activity among high and low risk human papillomavirus E2 proteins correlates with E2 DNA binding.
The Journal of biological chemistry
Animals; Bovine papillomavirus 1; Cell-Free System; DNA; DNA-Binding Proteins; Humans; Oncogene Proteins, Viral; Papillomaviridae; Promoter Regions, Genetic; Repressor Proteins; Risk Factors; Trans-Activators; Transcription Factors; Transcription, Genetic; Viral Proteins
The full-length E2 protein, encoded by human papillomaviruses (HPVs), is a sequence-specific transcription factor found in all HPVs, including cancer-causing high risk HPV types 16 and 18 and wart-inducing low risk HPV types 6 and 11. To investigate whether E2 proteins encoded by high risk HPVs may function differentially from E2 proteins encoded by low risk HPVs and animal papillomaviruses, we conducted comparative DNA-binding and transcription studies using electrophoretic mobility shift assays and cell-free transcription systems reconstituted with purified general transcription factors, cofactor, RNA polymerase II, and with E2 proteins encoded by HPV-16, HPV-18, HPV-11, and bovine papillomavirus type 1 (BPV-1). We found that although different types of E2 proteins all exhibited transactivation and repression activities, depending on the sequence context of the E2-binding sites, HPV-16 E2 shows stronger transcription activity and greater DNA-binding affinity than those displayed by the other E2 proteins. Surprisingly, HPV-18 E2 behaves more similarly to BPV-1 E2 than HPV-16 E2 in its functional properties. Our studies thus categorize HPV-18 E2 and BPV-1 E2 in the same protein family, a finding consistent with the available E2 structural data that separate the closely related HPV-16 and HPV-18 E2 proteins but classify together the more divergent BPV-1 and HPV-18 E2 proteins.
Neurosciences (Brain & Spine)
Hou, Samuel Y; Wu, Shwu-Yuan; and Chiang, Cheng-Ming, "Transcriptional activity among high and low risk human papillomavirus E2 proteins correlates with E2 DNA binding." (2002). Articles, Abstracts, and Reports. 881.
Samuel Hou is affiliated with Providence St. Joseph Health.