2crx
From Proteopedia
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==Overview== | ==Overview== | ||
| - | We have determined the X-ray crystal structures of two DNA Holliday | + | We have determined the X-ray crystal structures of two DNA Holliday junctions (HJs) bound by Cre recombinase. The HJ is a four-way branched structure that occurs as an intermediate in genetic recombination pathways, including site-specific recombination by the lambda-integrase family. Cre recombinase is an integrase family member that recombines 34 bp loxP sites in the absence of accessory proteins or auxiliary DNA sequences. The 2.7 A structure of Cre recombinase bound to an immobile HJ and the 2.5 A structure of Cre recombinase bound to a symmetric, nicked HJ reveal a nearly planar, twofold-symmetric DNA intermediate that shares features with both the stacked-X and the square conformations of the HJ that exist in the unbound state. The structures support a protein-mediated crossover isomerization of the junction that acts as the switch responsible for activation and deactivation of recombinase active sites. In this model, a subtle isomerization of the Cre recombinase-HJ quaternary structure dictates which strands are cleaved during resolution of the junction via a mechanism that involves neither branch migration nor helical restacking. |
==About this Structure== | ==About this Structure== | ||
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[[Category: Bacteriophage p1]] | [[Category: Bacteriophage p1]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Gopaul, D | + | [[Category: Gopaul, D N.]] |
[[Category: Guo, F.]] | [[Category: Guo, F.]] | ||
| - | [[Category: Vanduyne, G | + | [[Category: Vanduyne, G D.]] |
[[Category: cre recombinase]] | [[Category: cre recombinase]] | ||
[[Category: holliday junction]] | [[Category: holliday junction]] | ||
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[[Category: recombination]] | [[Category: recombination]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:51:48 2008'' |
Revision as of 14:51, 21 February 2008
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STRUCTURE OF THE HOLLIDAY JUNCTION INTERMEDIATE IN CRE-LOXP SITE-SPECIFIC RECOMBINATION
Overview
We have determined the X-ray crystal structures of two DNA Holliday junctions (HJs) bound by Cre recombinase. The HJ is a four-way branched structure that occurs as an intermediate in genetic recombination pathways, including site-specific recombination by the lambda-integrase family. Cre recombinase is an integrase family member that recombines 34 bp loxP sites in the absence of accessory proteins or auxiliary DNA sequences. The 2.7 A structure of Cre recombinase bound to an immobile HJ and the 2.5 A structure of Cre recombinase bound to a symmetric, nicked HJ reveal a nearly planar, twofold-symmetric DNA intermediate that shares features with both the stacked-X and the square conformations of the HJ that exist in the unbound state. The structures support a protein-mediated crossover isomerization of the junction that acts as the switch responsible for activation and deactivation of recombinase active sites. In this model, a subtle isomerization of the Cre recombinase-HJ quaternary structure dictates which strands are cleaved during resolution of the junction via a mechanism that involves neither branch migration nor helical restacking.
About this Structure
2CRX is a Single protein structure of sequence from Bacteriophage p1. Known structural/functional Sites: and . Full crystallographic information is available from OCA.
Reference
Structure of the Holliday junction intermediate in Cre-loxP site-specific recombination., Gopaul DN, Guo F, Van Duyne GD, EMBO J. 1998 Jul 15;17(14):4175-87. PMID:9670032
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