1B8I

STRUCTURE OF THE HOMEOTIC UBX/EXD/DNA TERNARY COMPLEX


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.4 Å
  • R-Value Free: 0.304 
  • R-Value Work: 0.224 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structure of a DNA-bound Ultrabithorax-Extradenticle homeodomain complex.

Passner, J.M.Ryoo, H.D.Shen, L.Mann, R.S.Aggarwal, A.K.

(1999) Nature 397: 714-719

  • DOI: 10.1038/17833

  • PubMed Abstract: 
  • During the development of multicellular organisms, gene expression must be tightly regulated, both spatially and temporally. One set of transcription factors that are important in animal development is encoded by the homeotic (Hox) genes, which gover ...

    During the development of multicellular organisms, gene expression must be tightly regulated, both spatially and temporally. One set of transcription factors that are important in animal development is encoded by the homeotic (Hox) genes, which govern the choice between alternative developmental pathways along the anterior-posterior axis. Hox proteins, such as Drosophila Ultrabithorax, have low DNA-binding specificity by themselves but gain affinity and specificity when they bind together with the homeoprotein Extradenticle (or Pbxl in mammals). To understand the structural basis of Hox-Extradenticle pairing, we determine here the crystal structure of an Ultrabithorax-Extradenticle-DNA complex at 2.4 A resolution, using the minimal polypeptides that form a cooperative heterodimer. The Ultrabithorax and Extradenticle homeodomains bind opposite faces of the DNA, with their DNA-recognition helices almost touching each other. However, most of the cooperative interactions arise from the YPWM amino-acid motif of Ultrabithorax-located amino-terminally to its homeodomain-which forms a reverse turn and inserts into a hydrophobic pocket on the Extradenticle homeodomain surface. Together, these protein-DNA and protein-protein interactions define the general principles by which homeotic proteins interact with Extradenticle (or Pbx1) to affect development along the anterior-posterior axis of animals.


    Organizational Affiliation

    Structural Biology Program, Department of Physiology and Biophysics, Mount Sinai School of Medicine, New York, New York 10029, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure


Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
PROTEIN (ULTRABITHORAX HOMEOTIC PROTEIN IV)
A
81Drosophila melanogasterMutation(s): 1 
Gene Names: Ubx
Find proteins for P83949 (Drosophila melanogaster)
Go to UniProtKB:  P83949
Entity ID: 4
MoleculeChainsSequence LengthOrganismDetails
PROTEIN (HOMEOBOX PROTEIN EXTRADENTICLE)
B
63Drosophila melanogasterMutation(s): 0 
Gene Names: exd
Find proteins for P40427 (Drosophila melanogaster)
Go to UniProtKB:  P40427
Entity ID: 1
MoleculeChainsLengthOrganism
DNA (5'-D(*GP*TP*CP*GP*CP*CP*AP*TP*AP*AP*AP*TP*CP*AP*C)-3')C15N/A
Entity ID: 2
MoleculeChainsLengthOrganism
DNA (5'-D(*AP*CP*GP*TP*GP*AP*TP*TP*TP*AP*TP*GP*GP*CP*G)-3')D15N/A
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.4 Å
  • R-Value Free: 0.304 
  • R-Value Work: 0.224 
  • Space Group: P 43 21 2
Unit Cell:
Length (Å)Angle (°)
a = 69.430α = 90.00
b = 69.430β = 90.00
c = 100.700γ = 90.00
Software Package:
Software NamePurpose
SHARPphasing
X-PLORrefinement
MLPHAREphasing
DENZOdata reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1999-04-12
    Type: Initial release
  • Version 1.1: 2008-04-26
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance