![]()
|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Papers In Press, published online ahead of print April 14, 2004
Department of Biochemistry, The Robert Wood Johnson Medical School, Piscataway, NJ 08854
Corresponding Author: patelss{at}umdnj.edu
While helicases participate in virtually every cellular process involving nucleic acids, the details of their mechanism including the role of interaction between the subunits remains unclear. Here we study the unwinding kinetics of the helicase from hepatitis C virus (HCV) using DNA substrates with a range of tail and duplex lengths. The binding of the helicase to the substrates was characterized by electron microscopy and fluorimetric titrations. Depending on the length of the ssDNA tail, one or more helicase molecules can be loaded on the DNA. Unwinding was measured under single-turnover conditions and the results show that a monomer is active on short duplexes, yet multiple molecules are needed to unwind long duplexes. Thus, increasing the ssDNA tail length increases the unwinding efficiency. The unwinding kinetics was modeled as a stepwise process performed by single or multiple helicase molecules. The model programmed in MATLAB was used for global fitting of the kinetics yielding values for the rate of unwinding, processivity, cooperativity, step size, and occlusion site. The results indicate that a single HCV helicase molecule unwinds DNA with a low processivity. The multiple helicase molecules present on the DNA substrate show functional cooperativity and unwind with greater efficiency, although they bind and release the substrate non-cooperatively and the ATPase cycle of the helicase molecules is not coordinated. The functional interaction model explains the efficient unwinding by multiple helicases and is generally applicable.
J. Biol. Chem, 10.1074/jbc.M403257200
Submitted on March 23, 2004
Revised on April 14, 2004
Accepted on April 14, 2004
The functional interaction of the hepatitis C virus helicase molecules is responsible for unwinding processivity
![]()
CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati What's this?
This article has been cited by other articles:
![]() |
B. Sikora, Y. Chen, C. F. Lichti, M. K. Harrison, T. A. Jennings, Y. Tang, A. J. Tackett, J. B. Jordan, J. Sakon, C. E. Cameron, et al. Hepatitis C Virus NS3 Helicase Forms Oligomeric Structures That Exhibit Optimal DNA Unwinding Activity in Vitro J. Biol. Chem., April 25, 2008; 283(17): 11516 - 11525. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Yang, S.-X. Dou, H. Ren, P.-Y. Wang, X.-D. Zhang, M. Qian, B.-Y. Pan, and X. G. Xi Evidence for a functional dimeric form of the PcrA helicase in DNA unwinding Nucleic Acids Res., April 1, 2008; 36(6): 1976 - 1989. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Gozdek, I. Zhukov, A. Polkowska, J. Poznanski, A. Stankiewicz-Drogon, J. M. Pawlowicz, W. Zagorski-Ostoja, P. Borowski, and A. M. Boguszewska-Chachulska NS3 Peptide, a Novel Potent Hepatitis C Virus NS3 Helicase Inhibitor: Its Mechanism of Action and Antiviral Activity in the Replicon System Antimicrob. Agents Chemother., February 1, 2008; 52(2): 393 - 401. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. L. Tellinghuisen, M. J. Evans, T. von Hahn, S. You, and C. M. Rice Studying Hepatitis C Virus: Making the Best of a Bad Virus J. Virol., September 1, 2007; 81(17): 8853 - 8867. [Full Text] [PDF] |
||||
![]() |
I. Donmez, V. Rajagopal, Y.-J. Jeong, and S. S. Patel Nucleic Acid Unwinding by Hepatitis C Virus and Bacteriophage T7 Helicases Is Sensitive to Base Pair Stability J. Biol. Chem., July 20, 2007; 282(29): 21116 - 21123. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Balistreri, J. Caldentey, L. Kaariainen, and T. Ahola Enzymatic Defects of the nsP2 Proteins of Semliki Forest Virus Temperature-Sensitive Mutants J. Virol., March 15, 2007; 81(6): 2849 - 2860. [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] |
||||
![]() |
B. Sikora, R. L. Eoff, S. W. Matson, and K. D. Raney DNA Unwinding by Escherichia coli DNA Helicase I (TraI) Provides Evidence for a Processive Monomeric Molecular Motor J. Biol. Chem., November 24, 2006; 281(47): 36110 - 36116. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Lionnet, A. Dawid, S. Bigot, F.-X. Barre, O. A. Saleh, F. Heslot, J.-F. Allemand, D. Bensimon, and V. Croquette DNA mechanics as a tool to probe helicase and translocase activity Nucleic Acids Res., September 10, 2006; 34(15): 4232 - 4244. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. G. Mackintosh and K. D. Raney DNA unwinding and protein displacement by superfamily 1 and superfamily 2 helicases Nucleic Acids Res., September 10, 2006; 34(15): 4154 - 4159. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. S. Patel and I. Donmez Mechanisms of Helicases J. Biol. Chem., July 7, 2006; 281(27): 18265 - 18268. [Full Text] [PDF] |
||||
![]() |
A. Sampath, T. Xu, A. Chao, D. Luo, J. Lescar, and S. G. Vasudevan Structure-based mutational analysis of the NS3 helicase from dengue virus. J. Virol., July 1, 2006; 80(13): 6686 - 6690. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. K. Byrd and K. D. Raney Displacement of a DNA binding protein by Dda helicase Nucleic Acids Res., May 31, 2006; 34(10): 3020 - 3029. [Abstract] [Full Text] [PDF] |
||||
![]() |
X.-D. Zhang, S.-X. Dou, P. Xie, J.-S. Hu, P.-Y. Wang, and X. G. Xi Escherichia coli RecQ Is a Rapid, Efficient, and Monomeric Helicase J. Biol. Chem., May 5, 2006; 281(18): 12655 - 12663. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. G. Mackintosh, J. Z. Lu, J. B. Jordan, M. K. Harrison, B. Sikora, S. D. Sharma, C. E. Cameron, K. D. Raney, and J. Sakon Structural and Biological Identification of Residues on the Surface of NS3 Helicase Required for Optimal Replication of the Hepatitis C Virus J. Biol. Chem., February 10, 2006; 281(6): 3528 - 3535. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Yon, T. Teramoto, N. Mueller, J. Phelan, V. K. Ganesh, K. H. M. Murthy, and R. Padmanabhan Modulation of the Nucleoside Triphosphatase/RNA Helicase and 5'-RNA Triphosphatase Activities of Dengue Virus Type 2 Nonstructural Protein 3 (NS3) by Interaction with NS5, the RNA-dependent RNA Polymerase J. Biol. Chem., July 22, 2005; 280(29): 27412 - 27419. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. M. Brendza, W. Cheng, C. J. Fischer, M. A. Chesnik, A. Niedziela-Majka, and T. M. Lohman Autoinhibition of Escherichia coli Rep monomer helicase activity by its 2B subdomain PNAS, July 19, 2005; 102(29): 10076 - 10081. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. J. Tackett, Y. Chen, C. E. Cameron, and K. D. Raney Multiple Full-length NS3 Molecules Are Required for Optimal Unwinding of Oligonucleotide DNA in Vitro J. Biol. Chem., March 18, 2005; 280(11): 10797 - 10806. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. M. I. Lam, R. S. Rypma, and D. N. Frick Enhanced nucleic acid binding to ATP-bound hepatitis C virus NS3 helicase at low pH activates RNA unwinding Nucleic Acids Res., August 2, 2004; 32(13): 4060 - 4070. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. L. Garcia, G. Bradley, C. J. Hayes, S. Krintel, P. Soultanas, and P. Janscak RPA alleviates the inhibitory effect of vinylphosphonate internucleotide linkages on DNA unwinding by BLM and WRN helicases Nucleic Acids Res., July 15, 2004; 32(12): 3771 - 3778. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| All ASBMB Journals | Molecular and Cellular Proteomics |
| Journal of Lipid Research | ASBMB Today |