Involvement of template-activating factor I/SET in transcription of adenovirus early genes as a positive-acting factor

J Virol. 2006 Jan;80(2):794-801. doi: 10.1128/JVI.80.2.794-801.2006.

Abstract

The adenovirus genome complexed with viral core protein VII (adenovirus DNA-protein VII complex) at least is the bona fide template for transcription of adenovirus early genes. It is believed that the highly basic protein VII, like cellular histones, is a negative regulator for genome functions. Analyses with in vitro replication and transcription systems using the adenovirus DNA-protein VII complex have revealed that remodeling of the complex is crucial for efficient DNA replication and transcription. We identified host acidic proteins, template-activating factor I (TAF-I), TAF-II, and TAF-III as stimulatory factors for replication from the adenovirus DNA-protein VII complex. Recently, it was reported that the adenovirus DNA interacts with TAF-I and pp32, another host acidic protein (Y. Xue, J. S. Johnson, D. A. Ornelles, J. Lieberman, and D. A. Engel, J. Virol. 79:2474-2483, 2005). We found that TAF-I interacts and colocalizes with protein VII in adenovirus-infected cells during the early phases of infection, but pp32 does not. Although pp32 had the potential ability to interact with protein VII, pp32 did not remodel the adenovirus DNA-protein VII complex in vitro. Small interfering RNA-mediated knockdown of TAF-I expression leads to the delay of the transcription timing of early genes. These results provide evidence that TAF-I plays an important role in the early stages of the adenovirus infection cycle.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenoviridae / genetics*
  • Adenoviridae Infections / virology
  • Cell Nucleus / metabolism
  • Chromosomal Proteins, Non-Histone / genetics*
  • Chromosomal Proteins, Non-Histone / metabolism
  • Chromosomal Proteins, Non-Histone / physiology
  • DNA-Binding Proteins
  • Gene Expression Regulation, Viral
  • HeLa Cells
  • Histone Chaperones
  • Humans
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism
  • Phosphoproteins / genetics
  • Phosphoproteins / metabolism
  • Templates, Genetic
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism
  • Transcription Factors / physiology
  • Transcription, Genetic
  • Viral Core Proteins / metabolism

Substances

  • Chromosomal Proteins, Non-Histone
  • DNA-Binding Proteins
  • Histone Chaperones
  • Nuclear Proteins
  • Phosphoproteins
  • SET protein, human
  • Transcription Factors
  • Viral Core Proteins