1ZQ3

NMR Solution Structure of the Bicoid Homeodomain Bound to the Consensus DNA Binding Site TAATCC

Summary for 1ZQ3

• Entry DOI: 10.2210/pdb1zq3/pdb
• Descriptor: 5'-D(*GP*CP*TP*CP*TP*AP*AP*TP*CP*CP*CP*CP*G)-3', 5'-D(*CP*GP*GP*GP*GP*AP*TP*TP*AP*GP*AP*GP*C)-3', Homeotic bicoid protein (3 entities in total)
• Functional Keywords: protein-dna complex, double helix, helix-turn-helix, homeodomain, dna-binding domain, k50, recognition helix, transcription factor, translational control, transcription-dna complex, transcription/dna
• Biological source: Drosophila melanogaster (fruit fly)
• Cellular location: Nucleus: Q9UAM0
• Total number of polymer chains: 3
• Total formula weight: 15907.25

Authors

Baird-Titus, J.M.,Rance, M.,Clark-Baldwin, K.,Ma, J.,Vrushank, D. (deposition date: 2005-05-18, release date: 2006-02-14, Last modification date: 2024-05-22)

Primary citation

Baird-Titus, J.M.,Clark-Baldwin, K.,Dave, V.,Caperelli, C.A.,Ma, J.,Rance, M.
The solution structure of the native K50 Bicoid homeodomain bound to the consensus TAATCC DNA-binding site.
J.Mol.Biol., 356:1137-1151, 2006

PubMed Abstract: The solution structure of the homeodomain of the Drosophila morphogenic protein Bicoid (Bcd) complexed with a TAATCC DNA site is described. Bicoid is the only known protein that uses a homeodomain to regulate translation, as well as transcription, by binding to both RNA and DNA during early Drosophila development; in addition, the Bcd homeodomain can recognize an array of different DNA sites. The dual functionality and broad recognition capabilities signify that the Bcd homeodomain may possess unique structural/dynamic properties. Bicoid is the founding member of the K50 class of homeodomain proteins, containing a lysine residue at the critical 50th position (K50) of the homeodomain sequence, a residue required for DNA and RNA recognition; Bcd also has an arginine residue at the 54th position (R54), which is essential for RNA recognition. Bcd is the only known homeodomain with the K50/R54 combination of residues. The Bcd structure indicates that this homeodomain conforms to the conserved topology of the homeodomain motif, but exhibits a significant variation from other homeodomain structures at the end of helix 1. A key result is the observation that the side-chains of the DNA-contacting residues K50, N51 and R54 all show strong signs of flexibility in the protein-DNA interface. This finding is supportive of the adaptive-recognition theory of protein-DNA interactions.

PubMed: 16406070
DOI: 10.1016/j.jmb.2005.12.007

Experimental method

SOLUTION NMR