Crystallization and characterization of the thallium form of the Oxytricha nova G-quadruplex.

ABSTRACT: The crystal structure of the Tl+ form of the G-quadruplex formed from the Oxytricha nova telomere sequence, d(G4T4G4), has been solved to 1.55 A. This G-quadruplex contains five Tl+ ions, three of which are interspersed between adjacent G-quartet planes and one in each of the two thymine loops. The structure displays a high degree of similarity to the K+ crystal structure [Haider et al. (2002), J. Mol. Biol., 320, 189-200], including the number and location of the monovalent cation binding sites. The highly isomorphic nature of the two structures, which contain such a large number of monovalent binding sites (relative to nucleic acid content), verifies the ability of Tl+ to mimic K+ in nucleic acids. Information from this report confirms and extends the assignment of 205Tl resonances from

SUBMITTER: Gill ML 

PROVIDER: S-EPMC1636370 | biostudies-literature | 2006

REPOSITORIES: biostudies-literature