From Proteopedia
(Difference between revisions)
proteopedia linkproteopedia link
|
|
Line 1: |
Line 1: |
- | [[Image:1t4x.gif|left|200px]] | + | {{Seed}} |
| + | [[Image:1t4x.png|left|200px]] |
| | | |
| <!-- | | <!-- |
Line 9: |
Line 10: |
| {{STRUCTURE_1t4x| PDB=1t4x | SCENE= }} | | {{STRUCTURE_1t4x| PDB=1t4x | SCENE= }} |
| | | |
- | '''The first left-handed RNA structure of (CGCGCG)2, Z-RNA, NMR, 12 structures, determined in high salt'''
| + | ===The first left-handed RNA structure of (CGCGCG)2, Z-RNA, NMR, 12 structures, determined in high salt=== |
| | | |
| | | |
- | ==Overview==
| + | <!-- |
- | Right-handed RNA duplexes of (CG)n sequence undergo salt-induced helicity reversal, forming left-handed RNA double helices (Z-RNA). In contrast to the thoroughly studied Z-DNA, no Z-RNA structure of natural origin is known. Here we report the NMR structure of a half-turn, left-handed RNA helix (CGCGCG)2 determined in 6 M NaClO4. This is the first nucleic acid motif determined at such high salt. Sequential assignments of non-exchangeable proton resonances of the Z-form were based on the hitherto unreported NOE connectivity path [H6(n)-H5'/H5''(n)-H8(n+1)-H1'(n+1)-H6(n+2)] found for left-handed helices. Z-RNA structure shows several conformational features significantly different from Z-DNA. Intra-strand but no inter-strand base stacking was observed for both CpG and GpC steps. Helical twist angles for CpG steps have small positive values (4-7 degrees), whereas GpC steps have large negative values (-61 degrees). In the full-turn model of Z-RNA (12.4 bp per turn), base pairs are much closer to the helix axis than in Z-DNA, thus both the very deep, narrow minor groove with buried cytidine 2'-OH groups, and the major groove are well defined. The 2'-OH group of cytidines plays a crucial role in the Z-RNA structure and its formation; 2'-O-methylation of cytidine, but not of guanosine residues prohibits A to Z helicity reversal.
| + | The line below this paragraph, {{ABSTRACT_PUBMED_15292450}}, adds the Publication Abstract to the page |
| + | (as it appears on PubMed at http://www.pubmed.gov), where 15292450 is the PubMed ID number. |
| + | --> |
| + | {{ABSTRACT_PUBMED_15292450}} |
| | | |
| ==About this Structure== | | ==About this Structure== |
- | Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1T4X OCA]. | + | Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1T4X OCA]. |
| | | |
| ==Reference== | | ==Reference== |
Line 25: |
Line 29: |
| [[Category: Left-handed rna duplex]] | | [[Category: Left-handed rna duplex]] |
| [[Category: Z-rna]] | | [[Category: Z-rna]] |
- | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 09:32:05 2008'' | + | |
| + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Jul 28 07:17:41 2008'' |
Revision as of 04:17, 28 July 2008
Template:STRUCTURE 1t4x
The first left-handed RNA structure of (CGCGCG)2, Z-RNA, NMR, 12 structures, determined in high salt
Template:ABSTRACT PUBMED 15292450
About this Structure
Full experimental information is available from OCA.
Reference
High salt solution structure of a left-handed RNA double helix., Popenda M, Milecki J, Adamiak RW, Nucleic Acids Res. 2004 Aug 3;32(13):4044-54. Print 2004. PMID:15292450
Page seeded by OCA on Mon Jul 28 07:17:41 2008