Nucleic Acids Research, 1987, Vol. 15, No. 21 8877-8898
© 1987
Articles |
The cohering telomeres of Oxytricha
Helicon Foundation 4622 Santa Fe Street, San Diego, CA 92109, USA
Received May 21, 1987. Revised September 2, 1987. Accepted September 2, 1987.
We have studied the process by which purified Oxytricha macronuclear DNA associates with itself to form large aggregates. The various macronuclear DNA molecules all have the same terminal or telomeric DNA sequences that are shown below.
5' C4A4C4A4C4––mean length––––G4T4G4T4G4T4G4T4G4G4T4G4T4G4T4G4T4G4–––––2.4 kb––––––C4A4C4A4C4
When incubated at high concentrations, these telomeric sequences cohere with one another to form an unusual structure - one that is quite different from any DNA structure so far described. The evidence for this is the following: 1) These sequences cohere albeit slowly, in the presence of relatively high concentrations of Na+, and no other cation tested. This contras with the rapid coherence of complementary single-chain terminals of normal DNA (sticky ends) which occurs in the presence of any cation tested. 2) If the cohered form is transferred into buffers containing a special cation, K+, it becomes much more resistant to dissociation by heating. We estimate that K+ increases the thermal stability by 250 or more. The only precedent known (to us) for a cation-specific stabilization is that seen in the quadruplex structure formed by poly I. The thermal stability of double helical macronuclear DNA depends on the cation concentration, but not the cation type.
Limited treatment with specific nucleases show that the 3' and 5'-ended strands are essential for the formation of the cohering structure. Once in the cohered form, the telomeric sequences are protected from the action of nucleases. Coherence is inhibited by specific, but not by non-specific, synthetic oligomers, and by short telomeric fragments with or without their terminal single chains. We conclude that the coherence occurs by the formation of a novel condensed structure that involves the terminal nucleotides in three or four chains.
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  S. Paramasivan and P. H. Bolton Mix and measure fluorescence screening for selective quadruplex binders Nucleic Acids Res., October 1, 2008; 36(17): e106 - e106. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. D. Cian and J.-L. Mergny Quadruplex ligands may act as molecular chaperones for tetramolecular quadruplex formation Nucleic Acids Res., April 3, 2007; 35(8): 2483 - 2493. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. L. Gill, S. A. Strobel, and J. P. Loria Crystallization and characterization of the thallium form of the Oxytricha nova G-quadruplex Nucleic Acids Res., September 11, 2006; 34(16): 4506 - 4514. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
I. N. Rujan, J. C. Meleney, and P. H. Bolton Vertebrate telomere repeat DNAs favor external loop propeller quadruplex structures in the presence of high concentrations of potassium Nucleic Acids Res., April 7, 2005; 33(6): 2022 - 2031. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J.-L. Mergny, J.-F. Riou, P. Mailliet, M.-P. Teulade-Fichou, and E. Gilson Natural and pharmacological regulation of telomerase Nucleic Acids Res., February 15, 2002; 30(4): 839 - 865. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Schaffitzel, I. Berger, J. Postberg, J. Hanes, H. J. Lipps, and A. Pluckthun In vitro generated antibodies specific for telomeric guanine-quadruplex DNA react with Stylonychia lemnae macronuclei PNAS, June 28, 2001; (2001) 141229498. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J.-L. Mergny, L. Lacroix, M.-P. Teulade-Fichou, C. Hounsou, L. Guittat, M. Hoarau, P. B. Arimondo, J.-P. Vigneron, J.-M. Lehn, J.-F. Riou, et al. Telomerase inhibitors based on quadruplex ligands selected by a fluorescence assay PNAS, March 13, 2001; 98(6): 3062 - 3067. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Koeppel, J.-F. Riou, A. Laoui, P. Mailliet, P. B. Arimondo, D. Labit, O. Petitgenet, C. Helene, and J.-L. Mergny Ethidium derivatives bind to G-quartets, inhibit telomerase and act as fluorescent probes for quadruplexes Nucleic Acids Res., March 1, 2001; 29(5): 1087 - 1096. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. N. Weitzmann, K. J. Woodford, and K. Usdin The Development and Use of a DNA Polymerase Arrest Assay for the Evaluation of Parameters Affecting Intrastrand Tetraplex Formation J. Biol. Chem., August 23, 1996; 271(34): 20958 - 20964. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Schaffitzel, I. Berger, J. Postberg, J. Hanes, H. J. Lipps, and A. Pluckthun In vitro generated antibodies specific for telomeric guanine-quadruplex DNA react with Stylonychia lemnae macronuclei PNAS, July 17, 2001; 98(15): 8572 - 8577. [Abstract] [Full Text] [PDF]
|
|