Alpha-DNA VIII: thermodynamic parameters of complexes formed between the oligo-alpha-deoxynucleotides: alpha-d(GGAAGG) and alpha-d(CCTTCC) and their complementary oligo-beta-deoxynucleotides: beta-d(CCTTCC) and beta-d(GGAAGG) are different.
The temperature dependence of the formation of a complex between an alpha-d(CCTTCC) hexanucleotide and its complementary beta-d(GGAAGG) sequence was studied and compared to the formation of the beta-d(CCTTCC):beta-d(GGAAGG) complex. Such alpha-beta complex is more stable than the regular beta:beta complex. The Tm value for the alpha:beta complex is 28 degrees C (delta G degrees = -7.3 kcal/mole) while Tm = 20, 1 degree C (delta G degrees = -6.3 kcal/mole) for the beta:beta complex. The stoechiometry of the alpha:beta complex corresponds to the formation of a 1:1 duplex. However, when the alpha- strand is made of alpha-purines: alpha-d(GGAAGG), the stability of the alpha:beta complex, alpha-d(GGAAGG):beta-d(CCTTCC) is found to be lower (Tm = 13.8 degrees C) than the stability of the regular beta-beta complex, leading to the conclusion that the nature of the alpha-sequence is important in terms of stability when considering the synthesis of such a sequence for using it as antisense oligonucleotide.
Paoletti
J
J
Unité de Biochemie, Institut Gustave Roussy, Villejuif, France.
Bazile
D
D
Morvan
F
F
Imbach
J L
JL
Paoletti
C
C
D001482:Base Composition; D001483:Base Sequence; D002942:Circular Dichroism; D009838:Oligodeoxyribonucleotides; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D013696:Temperature; D013816:Thermodynamics
D009838:Oligodeoxyribonucleotides