Involvement of template-activating factor I/SET in transcription of adenovirus early genes as a positive-acting factor.
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.
Haruki
Hirohito
H
Department of Infection Biology, Graduate School of Comprehensive Human Sciences and Institute of Basic Medical Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Japan.
Okuwaki
Mitsuru
M
Miyagishi
Makoto
M
Taira
Kazunari
K
Nagata
Kyosuke
K
D000256:Adenoviridae / Q000235:genetics*; D000257:Adenoviridae Infections / Q000821:virology; D002467:Cell Nucleus / Q000378:metabolism; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D004268:DNA-Binding Proteins; D015967:Gene Expression Regulation, Viral; D006367:HeLa Cells; D056488:Histone Chaperones; D006801:Humans; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism; D013698:Templates, Genetic; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D014158:Transcription, Genetic; D014758:Viral Core Proteins / Q000378:metabolism
D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins; D056488:Histone Chaperones; D009687:Nuclear Proteins; D010750:Phosphoproteins; C513473:SET protein, human; D014157:Transcription Factors; D014758:Viral Core Proteins