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

J. Biol. Chem., Vol. 280, Issue 24, 23397-23407, June 17, 2005

This Article Full Text Full Text (PDF) All Versions of this Article: 280/24/23397    most recent M414130200v1 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 Machwe, A. Articles by Orren, D. K. Search for Related Content PubMed PubMed Citation Articles by Machwe, A. Articles by Orren, D. K. Social Bookmarking                      What's this?

RecQ Family Members Combine Strand Pairing and Unwinding Activities to Catalyze Strand Exchange^*

Amrita Machwe, Liren Xiao, Joanna Groden, Steven W. Matson¶, and David K. Orren||

From the Graduate Center for Toxicology, University of Kentucky, Lexington, Kentucky 40536-0305, the Department of Molecular Genetics, Biochemistry, and Microbiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267, and the ^¶Department of Biology, University of North Carolina, Chapel Hill, North Carolina 27599

RecQ helicases are critical for maintaining genomic integrity. In this study, we show that three RecQ members (WRN, deficient in the Werner syndrome; BLM, deficient in the Bloom syndrome; and Drosophila melanogaster RecQ5b (dmRecQ5b)) possess a novel strand pairing activity. Furthermore, each of these enzymes combines this strand pairing activity with its inherent DNA unwinding capability to perform coordinated strand exchange. In this regard, WRN and BLM are considerably more efficient than dmRecQ5b, apparently because dmRecQ5b lacks conserved sequences C-terminal to the helicase domain that contribute to DNA binding, strand pairing, and strand exchange. Based on our findings, we postulate that certain RecQ helicases are structurally designed to accomplish strand exchange on complex replication and recombination intermediates. This is highly consistent with proposed roles for RecQ members in DNA metabolism and the illegitimate recombination and cancer-prone phenotypes associated with RecQ defects.

Received for publication, December 16, 2004 , and in revised form, April 7, 2005.

^* This work was supported by grants from the Ellison Medical Foundation and the University of Kentucky Research Foundation (to D. K. O.) and by NCI Grant R01 CA113371-01 from the National Institutes of Health (to D. K. O.). 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: Graduate Center for Toxicology, 356 Health Sciences Research Bldg., University of Kentucky, 800 Rose St., Lexington, KY 40536-0305. Tel.: 859-323-3612; Fax: 859-323-1059; E-mail: dkorre2{at}uky.edu.

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

This article has been cited by other articles:

				Y. Gu, Y. Masuda, and K. Kamiya Biochemical analysis of human PIF1 helicase and functions of its N-terminal domain Nucleic Acids Res., October 3, 2008; (2008) gkn609v1. [Abstract] [Full Text] [PDF]

				D. V. Bugreev, R. M. Brosh Jr., and A. V. Mazin RECQ1 Possesses DNA Branch Migration Activity J. Biol. Chem., July 18, 2008; 283(29): 20231 - 20242. [Abstract] [Full Text] [PDF]

				V. Popuri, C. Z. Bachrati, L. Muzzolini, G. Mosedale, S. Costantini, E. Giacomini, I. D. Hickson, and A. Vindigni The Human RecQ Helicases, BLM and RECQ1, Display Distinct DNA Substrate Specificities J. Biol. Chem., June 27, 2008; 283(26): 17766 - 17776. [Abstract] [Full Text] [PDF]

				S. M. Howell and D. W. Bray Amelanotic Melanoma in a Patient With Rothmund-Thomson Syndrome Arch Dermatol, March 1, 2008; 144(3): 416 - 417. [Full Text] [PDF]

				A. Machwe, L. Xiao, R. G. Lloyd, E. Bolt, and D. K. Orren Replication fork regression in vitro by the Werner syndrome protein (WRN): Holliday junction formation, the effect of leading arm structure and a potential role for WRN exonuclease activity Nucleic Acids Res., September 27, 2007; 35(17): 5729 - 5747. [Abstract] [Full Text] [PDF]

				M. McVey, S. L. Andersen, Y. Broze, and J. Sekelsky Multiple Functions of Drosophila BLM Helicase in Maintenance of Genome Stability Genetics, August 1, 2007; 176(4): 1979 - 1992. [Abstract] [Full Text] [PDF]

				F. V. Jacinto and M. Esteller Mutator pathways unleashed by epigenetic silencing in human cancer Mutagenesis, July 1, 2007; 22(4): 247 - 253. [Abstract] [Full Text] [PDF]

				B. T. Weinert and D. C. Rio DNA strand displacement, strand annealing and strand swapping by the Drosophila Bloom's syndrome helicase Nucleic Acids Res., February 28, 2007; 35(4): 1367 - 1376. [Abstract] [Full Text] [PDF]

				T. Masuda-Sasa, P. Polaczek, and J. L. Campbell Single Strand Annealing and ATP-independent Strand Exchange Activities of Yeast and Human DNA2: POSSIBLE ROLE IN OKAZAKI FRAGMENT MATURATION J. Biol. Chem., December 15, 2006; 281(50): 38555 - 38564. [Abstract] [Full Text] [PDF]

				R. Gupta, S. Sharma, K. M. Doherty, J. A. Sommers, S. B. Cantor, and R. M. Brosh Jr Inhibition of BACH1 (FANCJ) helicase by backbone discontinuity is overcome by increased motor ATPase or length of loading strand Nucleic Acids Res., December 2, 2006; 34(22): 6673 - 6683. [Abstract] [Full Text] [PDF]

				V. W. Choi, D. M. McCarty, and R. J. Samulski Host cell DNA repair pathways in adeno-associated viral genome processing. J. Virol., November 1, 2006; 80(21): 10346 - 10356. [Abstract] [Full Text] [PDF]

				J. D. Bartos, W. Wang, J. E. Pike, and R. A. Bambara Mechanisms by Which Bloom Protein Can Disrupt Recombination Intermediates of Okazaki Fragment Maturation J. Biol. Chem., October 27, 2006; 281(43): 32227 - 32239. [Abstract] [Full Text] [PDF]

				R. Kanagaraj, N. Saydam, P. L. Garcia, L. Zheng, and P. Janscak Human RECQ5{beta} helicase promotes strand exchange on synthetic DNA structures resembling a stalled replication fork Nucleic Acids Res., October 6, 2006; (2006) gkl677v4. [Abstract] [Full Text] [PDF]

				M. P. Killoran and J. L. Keck Sit down, relax and unwind: structural insights into RecQ helicase mechanisms Nucleic Acids Res., September 10, 2006; 34(15): 4098 - 4105. [Abstract] [Full Text] [PDF]

				C. Ralf, I. D. Hickson, and L. Wu The Bloom's Syndrome Helicase Can Promote the Regression of a Model Replication Fork J. Biol. Chem., August 11, 2006; 281(32): 22839 - 22846. [Abstract] [Full Text] [PDF]

				M. Muftuoglu, S. Sharma, T. Thorslund, T. Stevnsner, M. M. Soerensen, R. M. Brosh Jr, and V. A. Bohr Cockayne syndrome group B protein has novel strand annealing and exchange activities Nucleic Acids Res., January 12, 2006; 34(1): 295 - 304. [Abstract] [Full Text] [PDF]

				C. Z. Bachrati, R. H. Borts, and I. D. Hickson Mobile D-loops are a preferred substrate for the Bloom's syndrome helicase. Nucleic Acids Res., January 1, 2006; 34(8): 2269 - 2279. [Abstract] [Full Text] [PDF]

				S. Sharma, J. A. Sommers, R. K. Gary, E. Friedrich-Heineken, U. Hubscher, and R. M. Brosh Jr The interaction site of Flap Endonuclease-1 with WRN helicase suggests a coordination of WRN and PCNA Nucleic Acids Res., December 2, 2005; 33(21): 6769 - 6781. [Abstract] [Full Text] [PDF]

				C. F. Cheok, L. Wu, P. L. Garcia, P. Janscak, and I. D. Hickson The Bloom's syndrome helicase promotes the annealing of complementary single-stranded DNA Nucleic Acids Res., July 15, 2005; 33(12): 3932 - 3941. [Abstract] [Full Text] [PDF]