Novel cellular interacting partners of the human papillomavirus 16 transcription/replication factor E2

Human papillomaviruses (HPVs) are causative agents in a number of human diseases. HPV can be divided into two groups: low risk that cause diseases such as genital warts, and high risk that cause ano-genital cancers. Of the high-risk group, HPV16 is the most commonly found in cervical cancer. All HPV encode an E2 protein and this protein regulates transcription from, and replication of, the viral genome making it essential for the viral life cycle. In order to function E2 must interact with cellular proteins; identification of these cellular partners will provide targets for disruption of the viral life cycle and will also provide insights into the processes of transcription and replication. To identify the cellular interacting partners for HPV16 E2, we carried out a yeast two-hybrid screen with the amino-terminus of E2 that is essential for mediating transcription and replication. Here we describe how this screen was carried out and detail the interacting partners that were identified; these include the proteins TopBP1, RACK1, POMP, p27BBP, ODC antizyme, and Delta-adaptin. Several of these partners have characteristics that make them ideal candidates for mediating E2 function.