T. Shida et al., CHARACTERIZATION OF TELOMERIC OLIGONUCLEOTIDES - FIDELITY OF REPETITIVE NUCLEOTIDE-SEQUENCES, Nucleosides & nucleotides, 17(1-3), 1998, pp. 575-584
To clarify the reasons for the high fidelity of repetitive telomeric s
equences, a series of d(TTXGGG)(4) (X: A, G, C, and T) were synthesize
d and characterized by UV absorption, CD, chemical modification, and r
esistance to nucleases. d(TTCGGG)(4), which is lacking in nature, has
similar structural stability and resistance to nucleases, compared wit
h d(TTAGGG)(4), which is widely present at the telomeres of many organ
isms. d(TTGGGG)(4) is the most stable as a result of formation of the
four G-quartet layers in the presence of potassium ion.