1ftz
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NUCLEAR MAGNETIC RESONANCE SOLUTION STRUCTURE OF THE FUSHI TARAZU HOMEODOMAIN FROM DROSOPHILA AND COMPARISON WITH THE ANTENNAPEDIA HOMEODOMAIN
OverviewOverview
The three-dimensional structure of a recombinant 70-residue polypeptide, containing the complete fushi tarazu (ftz) homeodomain from Drosophila, melanogaster has been determined by nuclear magnetic resonance (NMR), spectroscopy in solution. On the basis of 915 upper distance constraints, derived from nuclear Overhauser effects and 178 dihedral angle, constraints, a group of 20 conformers representing the solution structure, of the ftz homeodomain was computed with the program DIANA and, energy-minimized with the program OPAL. The average of the pairwise, root-mean-square deviations of the individual NMR conformers relative to, the mean coordinates is 0.50 A for the backbone atoms N, C alpha and C' of, residues 8 to 53. The molecular architecture includes three helices, comprising the residues 10 to 21, 28 to 38, and 42 to 52, a loop of, residues 22 to 27 between the helices I and II, and a turn of residues 39, to 41 linking the helices II and III. Comparisons with the structure of, the mutant Antennapedia homeodomain with Cys39 replaced by Ser, Antp, (C39S), shows that the two proteins contain the same molecular fold for, residues 8 to 53, whereas the more flexible fourth helix comprising, residues 53 to 59 in the Antp (C39S) homeodomain has no counterpart in the, ftz homeodomain. Considering that important intermolecular interactions in, the DNA complexes with the Antp, engrailed and Mat alpha 2 homeodomains, involve the fourth helix, it was rather unexpected that the stability of, the complex of ftz with the BS2 operator site was found to be comparable, to or even somewhat higher than that of the Antp complex with BS2. Another, difference is that the Antp homeodomain is more stable with respect to, thermal denaturation, with denaturation temperatures at pH 4.8 of 27, degrees C and 48 degrees C, respectively, for ftz and Antp.
About this StructureAbout this Structure
1FTZ is a Single protein structure of sequence from Drosophila melanogaster. Full crystallographic information is available from OCA.
ReferenceReference
Nuclear magnetic resonance solution structure of the fushi tarazu homeodomain from Drosophila and comparison with the Antennapedia homeodomain., Qian YQ, Furukubo-Tokunaga K, Resendez-Perez D, Muller M, Gehring WJ, Wuthrich K, J Mol Biol. 1994 May 6;238(3):333-45. PMID:7909851
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