HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

J. Biol. Chem., Vol. 278, Issue 32, 29649-29654, August 8, 2003

This Article Full Text Full Text (PDF) All Versions of this Article: 278/32/29649    most recent M305399200v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Prasad, R. Articles by Wilson, S. H. Search for Related Content PubMed PubMed Citation Articles by Prasad, R. Articles by Wilson, S. H. Social Bookmarking                      What's this?

Localization of the Deoxyribose Phosphate Lyase Active Site in Human DNA Polymerase by Controlled Proteolysis^*

Rajendra Prasad , Katarzyna Bebenek , Esther Hou , David D. Shock , William A. Beard , Roger Woodgate , Thomas A. Kunkel  and Samuel H. Wilson  ¶

From the Laboratory of Structural Biology, NIEHS, National Institutes of Health, Research Triangle Park, North Carolina 27709 and the Section on DNA Replication, Repair, and Mutagenesis, NICHD, National Institutes of Health, Bethesda, Maryland 20892

Human DNA polymerase (pol ) is a member of the Y-family of low fidelity lesion bypass DNA polymerases. In addition to a probable role in DNA lesion bypass, this enzyme has recently been shown to be required for somatic hypermutation in human B-cells. We found earlier that human pol has deoxyribose phosphate (dRP) lyase activity and unusual specificity for activity during DNA synthesis, suggesting involvement in specialized forms of base excision repair (BER). Here, mapping of the domain structure of human pol by controlled proteolysis revealed that the enzyme has a 48-kDa NH₂-terminal domain and a protease resistant 40-kDa "core domain" spanning residues Met⁷⁹ to Met⁴⁴⁵. A covalently cross-linked pol -DNA complex, representing a trapped intermediate in the dRP lyase reaction, was subjected to controlled proteolysis. Cross-linking was mapped to the 40-kDa core domain, indicating that the dRP lyase active site is in this region. To further evaluate the BER capacity of the enzyme, the dRP lyase and DNA polymerase activities were characterized on DNA substrates representing BER intermediates, and we found that pol was able to complement the in vitro single-nucleotide BER deficiency of a DNA polymerase null cell extract.

Received for publication, May 22, 2003

^* The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

^¶ To whom correspondence should be addressed: 111 T.W. Alexander Dr., P. O. Box 12233, MD B2-06, Research Triangle Park, NC 27709. Tel.: 919-541-3267; Fax: 919-541-3592; E-mail: wilson5{at}niehs.nih.gov.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				C. N. Kundu, R. Balusu, A. S. Jaiswal, and S. Narayan Adenomatous polyposis coli-mediated hypersensitivity of mouse embryonic fibroblast cell lines to methylmethane sulfonate treatment: implication of base excision repair pathways Carcinogenesis, October 1, 2007; 28(10): 2089 - 2095. [Abstract] [Full Text] [PDF]

				R. N. Trivedi, K. H. Almeida, J. L. Fornsaglio, S. Schamus, and R. W. Sobol The Role of Base Excision Repair in the Sensitivity and Resistance to Temozolomide-Mediated Cell Death Cancer Res., July 15, 2005; 65(14): 6394 - 6400. [Abstract] [Full Text] [PDF]

				L. Haracska, L. Prakash, and S. Prakash A mechanism for the exclusion of low-fidelity human Y-family DNA polymerases from base excision repair Genes & Dev., November 15, 2003; 17(22): 2777 - 2785. [Abstract] [Full Text] [PDF]