In:
European Journal of Biochemistry, Wiley, Vol. 171, No. 1-2 ( 1988-01), p. 155-162
Abstract:
A 1 H‐NMR investigation was carried out on the tetranucleotides U‐m 6 2 A‐U‐m 6 2 A and m 6 2 A‐m 6 2 A‐U‐m 6 2 A (m 6 2 = N 6 ‐dimethyladenosine) as well as on the hybrid trinucleotide dA‐r(U‐A). An extensive comparison with m 6 2 A‐U‐m 6 2 A and other relevant compounds is made. Previous proton NMR studies on trinucleotides have shown that purine‐pyrimidine‐purine sequences prefer to adopt a mixture of states which have as a common feature that the interior pyrimidine residue bulges out, whereas the flanking purine residues stack upon each other. A stacking interaction on the 3′ side of the bulge is known to have no measurable effect on the bulge population. Chemical‐shift data, ribose ring conformational analysis and information from NOE experiments now show unambiguously that the moderate U(1)‐m 6 2 A(2) stack in U‐m 6 2 A‐U‐m 6 2 A diminishes the population of bulged‐out structures in favour of a regular stack. This tendency towards conformational transmission in the downstream 5′→3′direction is fully confirmed by the fact that the strong m 6 2 A(1)‐m 6 2 A(2) stack in the tetranucleotide m 6 2 A‐m 6 2 A‐U‐m 6 2 A virtually precludes the formation of bulged‐out structures. The conformational characteristics of dA‐r(U‐A) appear comparable with those of m 6 2 A‐U‐m 6 2 A, which indicates that the presence of a 2′‐hydroxyl group in the first purine residue is not a necessary prerequisite for the formation of a bulge.
Type of Medium:
Online Resource
ISSN:
0014-2956
,
1432-1033
DOI:
10.1111/ejb.1988.171.issue-1-2
DOI:
10.1111/j.1432-1033.1988.tb13771.x
Language:
English
Publisher:
Wiley
Publication Date:
1988
detail.hit.zdb_id:
1398347-7
detail.hit.zdb_id:
2172518-4
SSG:
12
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