Structure and Stability of a Dimeric G-Quadruplex Formed by Cyclic Oligonucleotides

نویسندگان

  • Joan Casals
  • Júlia Viladoms
  • Enrique Pedroso
  • Carlos González
چکیده

We have studied the structure and stability of the cyclic dodecamer d, containing two copies of the human telomeric repeat. In the presence of sodium, NMR data are consistent with a dimeric structure of the molecule in which two cycles self-associate forming a quadruplex with three guanine tetrads connected by edgewise loops. The two macrocycles are arranged in a parallel way, and the dimeric structure exhibits a high melting temperature. These results indicate that cyclization of the phosphodiester chain does not prevent quadruplex formation, although it affects the global topology of the quadruplex.

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عنوان ژورنال:

دوره 2010  شماره 

صفحات  -

تاریخ انتشار 2010