1jb7: Difference between revisions

Revision as of 14:20, 21 February 2008

DNA G-Quartets in a 1.86 A Resolution Structure of an Oxytricha nova Telomeric Protein-DNA Complex

OverviewOverview

The Oxytricha nova telomere end binding protein (OnTEBP) recognizes, binds and protects the single-stranded 3'-terminal DNA extension found at the ends of macronuclear chromosomes. The structure of this complex shows that the single strand GGGGTTTTGGGG DNA binds in a deep cleft between the two protein subunits of OnTEBP, adopting a non-helical and irregular conformation. In extending the resolution limit of this structure to 1.86 A, we were surprised to find a G-quartet linked dimer of the GGGGTTTTGGGG DNA also packing within the crystal lattice and interacting with the telomere end binding protein. The G-quartet DNA exhibits the same structure and topology as previously observed in solution by NMR with diagonally crossing d(TTTT) loops at either end of the four-stranded helix. Additionally, the crystal structure reveals clearly visible Na(+), and specific patterns of bound water molecules in the four non-equivalent grooves. Although the G-quartet:protein contact surfaces are modest and might simply represent crystal packing interactions, it is interesting to speculate that the two types of telomeric DNA-protein interactions observed here might both be important in telomere biology.

About this StructureAbout this Structure

1JB7 is a Protein complex structure of sequences from Sterkiella nova with and as ligands. Full crystallographic information is available from OCA.

ReferenceReference

DNA G-quartets in a 1.86 A resolution structure of an Oxytricha nova telomeric protein-DNA complex., Horvath MP, Schultz SC, J Mol Biol. 2001 Jul 6;310(2):367-77. PMID:11428895

Page seeded by OCA on Thu Feb 21 13:20:39 2008

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OCA

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-[[Image:1jb7.gif|left|200px]]<br /><applet load="1jb7" size="450" color="white" frame="true" align="right" spinBox="true"
+[[Image:1jb7.gif|left|200px]]<br /><applet load="1jb7" size="350" color="white" frame="true" align="right" spinBox="true"
 caption="1jb7, resolution 1.86&Aring;" />
 '''DNA G-Quartets in a 1.86 A Resolution Structure of an Oxytricha nova Telomeric Protein-DNA Complex'''<br />
 ==Overview==
-The Oxytricha nova telomere end binding protein (OnTEBP) recognizes, binds, and protects the single-stranded 3'-terminal DNA extension found at the, ends of macronuclear chromosomes. The structure of this complex shows that, the single strand GGGGTTTTGGGG DNA binds in a deep cleft between the two, protein subunits of OnTEBP, adopting a non-helical and irregular, conformation. In extending the resolution limit of this structure to 1.86, A, we were surprised to find a G-quartet linked dimer of the GGGGTTTTGGGG, DNA also packing within the crystal lattice and interacting with the, telomere end binding protein. The G-quartet DNA exhibits the same, structure and topology as previously observed in solution by NMR with, diagonally crossing d(TTTT) loops at either end of the four-stranded, helix. Additionally, the crystal structure reveals clearly visible Na(+), and specific patterns of bound water molecules in the four non-equivalent, grooves. Although the G-quartet:protein contact surfaces are modest and, might simply represent crystal packing interactions, it is interesting to, speculate that the two types of telomeric DNA-protein interactions, observed here might both be important in telomere biology.
+The Oxytricha nova telomere end binding protein (OnTEBP) recognizes, binds and protects the single-stranded 3'-terminal DNA extension found at the ends of macronuclear chromosomes. The structure of this complex shows that the single strand GGGGTTTTGGGG DNA binds in a deep cleft between the two protein subunits of OnTEBP, adopting a non-helical and irregular conformation. In extending the resolution limit of this structure to 1.86 A, we were surprised to find a G-quartet linked dimer of the GGGGTTTTGGGG DNA also packing within the crystal lattice and interacting with the telomere end binding protein. The G-quartet DNA exhibits the same structure and topology as previously observed in solution by NMR with diagonally crossing d(TTTT) loops at either end of the four-stranded helix. Additionally, the crystal structure reveals clearly visible Na(+), and specific patterns of bound water molecules in the four non-equivalent grooves. Although the G-quartet:protein contact surfaces are modest and might simply represent crystal packing interactions, it is interesting to speculate that the two types of telomeric DNA-protein interactions observed here might both be important in telomere biology.
 ==About this Structure==
-JB7 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Sterkiella_nova Sterkiella nova] with NA and CL as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1JB7 OCA].
+JB7 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Sterkiella_nova Sterkiella nova] with <scene name='pdbligand=NA:'>NA</scene> and <scene name='pdbligand=CL:'>CL</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JB7 OCA].
 ==Reference==
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 [[Category: Protein complex]]
 [[Category: Sterkiella nova]]
-[[Category: Horvath, M.P.]]
+[[Category: Horvath, M P.]]
-[[Category: Schultz, S.C.]]
+[[Category: Schultz, S C.]]
 [[Category: CL]]
 [[Category: NA]]
@@ Line 23: / Line 23: @@
 [[Category: telomere-binding protein]]
-''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Tue Nov 20 18:04:17 2007''
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:20:39 2008''