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1i9k
From Proteopedia
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[[Image:1i9k.gif|left|200px]] | [[Image:1i9k.gif|left|200px]] | ||
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| - | + | {{STRUCTURE_1i9k| PDB=1i9k | SCENE= }} | |
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'''THE RNA I-MOTIF''' | '''THE RNA I-MOTIF''' | ||
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==About this Structure== | ==About this Structure== | ||
| - | + | Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1I9K OCA]. | |
==Reference== | ==Reference== | ||
The RNA i-motif., Snoussi K, Nonin-Lecomte S, Leroy JL, J Mol Biol. 2001 May 25;309(1):139-53. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/11491284 11491284] | The RNA i-motif., Snoussi K, Nonin-Lecomte S, Leroy JL, J Mol Biol. 2001 May 25;309(1):139-53. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/11491284 11491284] | ||
| - | [[Category: Protein complex]] | ||
[[Category: Lerou, J L.]] | [[Category: Lerou, J L.]] | ||
[[Category: Nonin-Lecomte, S.]] | [[Category: Nonin-Lecomte, S.]] | ||
[[Category: Snoussi, K.]] | [[Category: Snoussi, K.]] | ||
| - | [[Category: | + | [[Category: I-motif]] |
| - | [[Category: | + | [[Category: Nmr]] |
| - | [[Category: | + | [[Category: Rna]] |
| - | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 19:44:33 2008'' | |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | |
Revision as of 16:44, 2 May 2008
THE RNA I-MOTIF
Overview
Oligodeoxynucleotides with stretches of cytidine residues associate into a four-stranded structure, the i-motif, in which two head-to-tail, intercalated, parallel-stranded duplexes are held together by hemiprotonated C.C+ pairs. We have investigated the possibility of forming an i-motif structure with C-rich ribonucleic acids. The four C-rich RNAs studied, r(UC5), r(C5), r(C5U) and r(UC3), associate into multiple intercalated structures at acidic pH. r(UC5) forms two i-motif structures that differ by their intercalation topologies. We report on a structural study of the main form and we analyze the small conformational differences found by comparison with the DNA i-motif. The stacking topology of the main structure avoids one of the six 2'-OH/2'-OH repulsive contacts expected in a fully intercalated structure. The C3'-endo pucker of the RNA sugars and the orientation of the intercalated C.C+ pairs result in a modest widening of the narrow grooves at the steps where the hydroxyl groups are in close contact. The free energy of the RNA i-motif, on average -4 kJ mol(-1) per C.C+ pair, is half of the value found in DNA i-motif structures.
About this Structure
Full crystallographic information is available from OCA.
Reference
The RNA i-motif., Snoussi K, Nonin-Lecomte S, Leroy JL, J Mol Biol. 2001 May 25;309(1):139-53. PMID:11491284 Page seeded by OCA on Fri May 2 19:44:33 2008
Categories: Lerou, J L. | Nonin-Lecomte, S. | Snoussi, K. | I-motif | Nmr | Rna
