From Proteopedia
(Difference between revisions)
proteopedia linkproteopedia link
|
|
| Line 1: |
Line 1: |
| - | [[Image:2hri.jpg|left|200px]] | + | {{Seed}} |
| | + | [[Image:2hri.png|left|200px]] |
| | | | |
| | <!-- | | <!-- |
| Line 9: |
Line 10: |
| | {{STRUCTURE_2hri| PDB=2hri | SCENE= }} | | {{STRUCTURE_2hri| PDB=2hri | SCENE= }} |
| | | | |
| - | '''A parallel stranded human telomeric quadruplex in complex with the porphyrin TMPyP4'''
| + | ===A parallel stranded human telomeric quadruplex in complex with the porphyrin TMPyP4=== |
| | | | |
| | | | |
| - | ==Overview==
| + | <!-- |
| - | Maintenance of telomere integrity is a hallmark of human cancer, and the single-stranded 3' ends of telomeric DNA are targets for small-molecule anticancer therapies. We report here the crystal structure of a bimolecular human telomeric quadruplex, of the sequence d(TAGGGTTAGGG), in a complex with the quadruplex-binding ligand 5,10,15,20-tetrakis(N-methyl-4-pyridyl)porphyrin (TMPyP4) to a resolution of 2.09 A. The DNA quadruplex topology is parallel-stranded with external double-chain-reversal propeller loops, consistent with previous structural determinations. The porphyrin molecules bind by stacking onto the TTA nucleotides, either as part of the external loop structure or at the 5' region of the stacked quadruplex. This involves stacked on hydrogen-bonded base pairs, formed from those nucleotides not involved in the formation of G-tetrads, and there are thus no direct ligand interactions with G-tetrads. This is in accord with the relative nonselectivity by TMPyP4 for quadruplex DNAs compared to duplex DNA. Porphyrin binding is achieved by remodeling of loops compared to the ligand-free structures. Implications for the design of quadruplex-binding ligands are discussed, together with a model for the formation of anaphase bridges, which are observed following cellular treatment with TMPyP4.
| + | The line below this paragraph, {{ABSTRACT_PUBMED_17274602}}, adds the Publication Abstract to the page |
| | + | (as it appears on PubMed at http://www.pubmed.gov), where 17274602 is the PubMed ID number. |
| | + | --> |
| | + | {{ABSTRACT_PUBMED_17274602}} |
| | | | |
| | ==About this Structure== | | ==About this Structure== |
| Line 30: |
Line 34: |
| | [[Category: Propeller]] | | [[Category: Propeller]] |
| | [[Category: Quadruplex]] | | [[Category: Quadruplex]] |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun May 4 06:37:35 2008'' | + | |
| | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Jul 28 09:06:13 2008'' |
Revision as of 06:06, 28 July 2008
Template:STRUCTURE 2hri
A parallel stranded human telomeric quadruplex in complex with the porphyrin TMPyP4
Template:ABSTRACT PUBMED 17274602
About this Structure
Full crystallographic information is available from OCA.
Reference
Structural basis for binding of porphyrin to human telomeres., Parkinson GN, Ghosh R, Neidle S, Biochemistry. 2007 Mar 6;46(9):2390-7. Epub 2007 Feb 3. PMID:17274602
Page seeded by OCA on Mon Jul 28 09:06:13 2008
