The expression of the transcription factor TAF1 is modified by the HPV16 E2 protein

Acta Virol. 2020;64(3):375-379. doi: 10.4149/av_2020_307.

Abstract

High-risk human papillomaviruses (e.g., HPV16 and 18) are associated with cervical cancer occurrence and development. The early viral gene E2 encodes a protein involved in several key processes in HPV biology, such as replication, genome segregation, and viral gene transcription. E2's presence also affects the expression of a variety of cellular genes involved in a wide range of biological processes, including cell cycle regulation and apoptosis, which are mediated by E2's interaction with cellular proteins. In this report, a lentiviral system was used to express the HPV16 E2 gene in the HPV-negative C-33A cell line for several weeks. E2 expression was measured by RT-qPCR and its biological activity was evaluated using a reporter gene. In HPV16 E2-positive cells, we observed a statistically significant increase in mRNA and protein levels of TAF1 and p27, a basal transcription factor and one of its target genes, respectively. To our knowledge, this is the first study showing that the viral protein HPV16 E2 upregulates TAF1 expression. This suggests that E2's expression promotes a transcriptionally-favorable cellular environment that allows HPV to successfully complete its replication cycle. Keywords: HPV16; E2 protein; transcription; TAF1 regulation.

MeSH terms

  • Cell Line
  • DNA-Binding Proteins / metabolism*
  • Gene Expression Regulation
  • Histone Acetyltransferases / metabolism*
  • Human papillomavirus 16
  • Humans
  • Oncogene Proteins, Viral / metabolism*
  • Papillomavirus Infections
  • TATA-Binding Protein Associated Factors / metabolism*
  • Transcription Factor TFIID / metabolism*

Substances

  • DNA-Binding Proteins
  • E2 protein, Human papillomavirus type 16
  • Oncogene Proteins, Viral
  • TATA-Binding Protein Associated Factors
  • Transcription Factor TFIID
  • Histone Acetyltransferases
  • TATA-binding protein associated factor 250 kDa