E6 Proteins from Multiple Human Betapapillomavirus Types Degrade Bak and Protect Keratinocytes from Apoptosis after UVB Irradiation

• DOI: 10.1128/jvi.00902-08
• Publication Date: 2008-08-21T00:15:13Z
• Authors: Michael P. Underb...; Heather L. Howie; Kristin M. Bedard; Jennifer I. Koop; Denise A. Galloway
• Keywords: BETA (programming language)

ABSTRACT Human papillomavirus (HPV) types from the beta genus (beta-HPVs) have been implicated in development of skin cancer. A potentially important aspect their carcinogenic role is ability E6 protein to degrade proapoptotic family member Bak, which gives cells survive UV damage. However, it unknown if Bak limited certain beta-HPV or whether expression keratinocytes affects other proteins for apoptosis signaling. We tested abilities several representative members beta-HPVs and protect UV-treated apoptosis. The type 5 (HPV5), -8, -20, -22, -38, -76, -92, -96, as well alpha HPV HPV16, all degraded prevented its accumulation following treatment but did not constitutively. In addition, when using HPV16 (16E6) 8E6 genera, respectively, degradation was dependent on E3 ubiquitin ligase, E6AP. Other regulators apoptotic signaling were examined found be unperturbed by proteins. Importantly, protected same extent 16E6-expressing cells. conclusion, possess reducing levels those cells, thus blocking intrinsic pathway.