Single molecule detection of direct, homologous, DNA/DNA pairingopen access
- Authors
- Danilowicz, C.; Lee, C. H.; Kim, Keunpil; Hatch, K.; Coljee, V. W.; Kleckner, N.; Prentiss, M.
- Issue Date
- Nov-2009
- Publisher
- NATL ACAD SCIENCES
- Keywords
- dsDNA; sequence-dependent
- Citation
- PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, v.106, no.47, pp 19824 - 19829
- Pages
- 6
- Journal Title
- PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
- Volume
- 106
- Number
- 47
- Start Page
- 19824
- End Page
- 19829
- URI
- https://scholarworks.bwise.kr/cau/handle/2019.sw.cau/57444
- DOI
- 10.1073/pnas.0911214106
- ISSN
- 0027-8424
1091-6490
- Abstract
- Using a parallel single molecule magnetic tweezers assay we demonstrate homologous pairing of two double-stranded (ds) DNA molecules in the absence of proteins, divalent metal ions, crowding agents, or free DNA ends. Pairing is accurate and rapid under physiological conditions of temperature and monovalent salt, even at DNA molecule concentrations orders of magnitude below those found in vivo, and in the presence of a large excess of nonspecific competitor DNA. Crowding agents further increase the reaction rate. Pairing is readily detected between regions of homology of 5 kb or more. Detected pairs are stable against thermal forces and shear forces up to 10 pN. These results strongly suggest that direct recognition of homology between chemically intact B-DNA molecules should be possible in vivo. The robustness of the observed signal raises the possibility that pairing might even be the "default" option, limited to desired situations by specific features. Protein-independent homologous pairing of intact dsDNA has been predicted theoretically, but further studies are needed to determine whether existing theories fit sequence length, temperature, and salt dependencies described here.
- Files in This Item
-
- Appears in
Collections - College of Natural Sciences > Department of Life Science > 1. Journal Articles
Items in ScholarWorks are protected by copyright, with all rights reserved, unless otherwise indicated.