Elsevier

Virology

Volume 296, Issue 1, 25 April 2002, Pages 107-116
Virology

Regular Article
Sequence-Specific Binding of Poly(ADP-Ribose) Polymerase-1 to the Human T Cell Leukemia Virus Type-I Tax Responsive Element

https://doi.org/10.1006/viro.2002.1385Get rights and content
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Abstract

We have previously identified poly(ADP-ribose) polymerase-1 (PARP-1) as a coactivator for the human T cell leukemia virus type I (HTLV-I) transcription activator Tax. While PARP-1 is believed to contribute to DNA repair, PARP-1 has been described as a coactivator for other transcription factors. Recent evidence suggests that PARP-1 forms complexes on cellular promoters, so we investigated PARP-1 complexes on the HTLV-I Tax responsive elements (TxREs) using an end-blocked DNA binding assay. We observed sequence-specific binding of PARP-1 to the TxREs. The DNA binding domain of PARP-1 was fused to the transcriptional activation domain of VP16, and this fusion protein activated the HTLV-I promoter in a TxRE-dependent manner. Internal, sequence-specific binding of PARP-1 to DNA provides a mechanism for transcriptional regulation of the HTLV-I promoter. The mechanism of PARP-1 function in the HTLV-I system may have common mechanistic steps with other cellular promoters, including the formation of active complexes on the promoter.

Keywords

HTLV-I
Tax
PARP-1
transcription
coactivator
TxRE
DNA binding
CREB

Cited by (0)

1

Present address: Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, MI 48201.

2

To whom correspondence and reprint requests should be addressed at Institute of Molecular Medicine and Genetics, Medical College of Georgia, 1120 15th Street, Augusta, GA 30912. Fax: 706-721-8752. E-mail: [email protected].