This Article Full Text Full Text (PDF) Other Versions of this Article: MCB.01314-07v1 27/21/7475    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Wacker, D. A. Articles by Kraus, W. L. Search for Related Content PubMed PubMed Citation Articles by Wacker, D. A. Articles by Kraus, W. L.

 Previous Article  |  Next Article 

Molecular and Cellular Biology, November 2007, p. 7475-7485, Vol. 27, No. 21
0270-7306/07/$08.00+0     doi:10.1128/MCB.01314-07
Copyright © 2007, American Society for Microbiology. All Rights Reserved.

The DNA Binding and Catalytic Domains of Poly(ADP-Ribose) Polymerase 1 Cooperate in the Regulation of Chromatin Structure and Transcription

David A. Wacker ,^1,2,, Donald D. Ruhl,^1, Ehsan H. Balagamwala,¹ Kristine M. Hope,^1,3 Tong Zhang,¹ and W. Lee Kraus^1,3,4*

Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853,¹ Graduate Field of Biophysics, Cornell University, Ithaca, New York 14853,² Graduate Field of Environmental Toxicology, Cornell University, Ithaca, New York 14853,³ Department of Pharmacology, Weill Medical College of Cornell University, New York, New York 10021⁴

Received 21 July 2007/ Accepted 16 August 2007

We explored the mechanisms of chromatin compaction and transcriptional regulation by poly(ADP-ribose) polymerase 1 (PARP-1), a nucleosome-binding protein with an NAD⁺-dependent enzymatic activity. By using atomic force microscopy and a complementary set of biochemical assays with reconstituted chromatin, we showed that PARP-1 promotes the localized compaction of chromatin into supranucleosomal structures in a manner independent of the amino-terminal tails of core histones. In addition, we defined the domains of PARP-1 required for nucleosome binding, chromatin compaction, and transcriptional repression. Our results indicate that the DNA binding domain (DBD) of PARP-1 is necessary and sufficient for binding to nucleosomes, yet the DBD alone is unable to promote chromatin compaction and only partially represses RNA polymerase II-dependent transcription in an in vitro assay with chromatin templates (50% of the repression observed with wild-type PARP-1). Furthermore, our results show that the catalytic domain of PARP-1, which does not bind nucleosomes on its own, cooperates with the DBD to promote chromatin compaction and efficient transcriptional repression in a manner independent of its enzymatic activity. Collectively, our results have revealed a novel function for the catalytic domain in chromatin compaction. In addition, they show that the DBD and catalytic domain cooperate to regulate chromatin structure and chromatin-dependent transcription, providing mechanistic insights into how these domains contribute to the chromatin-dependent functions of PARP-1.

Published ahead of print on 4 September 2007.

Present address: School of Medicine, Yale University, New Haven, CT 06510.

D.A.W. and D.D.R. contributed equally to this work.

This article has been cited by other articles:

• Godon, C., Cordelieres, F. P., Biard, D., Giocanti, N., Megnin-Chanet, F., Hall, J., Favaudon, V. (2008). PARP inhibition versus PARP-1 silencing: different outcomes in terms of single-strand break repair and radiation susceptibility. Nucleic Acids Res 36: 4454-4464 [Abstract] [Full Text]  
• Pacher, P., Szabo, C. (2008). Role of the Peroxynitrite-Poly(ADP-Ribose) Polymerase Pathway in Human Disease. Am. J. Pathol. 173: 2-13 [Abstract] [Full Text]  
• Krishnakumar, R., Gamble, M. J., Frizzell, K. M., Berrocal, J. G., Kininis, M., Kraus, W. L. (2008). Reciprocal Binding of PARP-1 and Histone H1 at Promoters Specifies Transcriptional Outcomes. Science 319: 819-821 [Abstract] [Full Text]