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1akx
From Proteopedia
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| Ligands: | , , , , | ||||||
| Related: | 1AJU
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
HIV-2 TRANS ACTIVATING REGION RNA COMPLEX WITH ARGININAMIDE, NMR, MINIMIZED AVERAGE STRUCTURE
Overview
The trans-activating region (TAR) RNA-Tat protein interaction is important for activation of transciption in the human immunodeficiency virus (HIV). A model complex for this interaction composed of the two base bulge HIV-2 TAR and the amide derivative of arginine was studied by multidimensional heteronuclear NMR. Because of the improved spectral properties of the HIV-2 TAR complex, a larger number of NOEs in the bulge region were observed than in earlier studies of the HIV-1 TAR-argininamide complex. A total of 681 NOE distance restraints were collected and used to determine the solution structure of the HIV-2 TAR-argininamide complex. As observed in the previously proposed model from this lab, the two A-form stems co-axially stack and the critical U23 and the argininamide are located in the major groove. Model calculations including non-experimental restraints indicate that U23 is within hydrogen bonding distance to A27 consistent with the formation of a U x A x U base-triple. Base-triple formation helps open the major groove to increase the accessibility of G26 to hydrogen bond donors from the guanidinium group of argininamide. Argininamide binding is stabilized by stacking of the guanidinium group between the bases of A22 and U23, forming an argininamide sandwich.
About this Structure
1AKX is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.
Reference
Solution structure of the HIV-2 TAR-argininamide complex., Brodsky AS, Williamson JR, J Mol Biol. 1997 Apr 4;267(3):624-39. PMID:9126842
Page seeded by OCA on Sun Mar 30 18:42:24 2008
