Biological Assembly 1  

 3D View: Structure

Standalone Viewers  
Protein Workshop | Ligand Explorer

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 28196.50 
• Atom Count: 1923 
• Residue Count: 172 
• Unique protein chains: 1
• Unique nucleic acid chains: 2

1AN4

STRUCTURE AND FUNCTION OF THE B/HLH/Z DOMAIN OF USF

• DOI: 10.2210/pdb1AN4/pdb
• NDB: PDT027

• Classification: TRANSCRIPTION/DNA
• Organism(s): Homo sapiens
• Expression System: Bacteria
• Mutation(s): 2 


• Deposited: 1997-03-15 Released: 1997-09-17 
• Deposition Author(s): Ferre-D'Amare, A.R., Pognonec, P., Roeder, R.G., Burley, S.K.

---

Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.9 Å
• R-Value Work: 0.236 

Literature

Structure and function of the b/HLH/Z domain of USF.

Ferre-D'Amare, A.R., Pognonec, P., Roeder, R.G., Burley, S.K.

(1994) EMBO J. 13: 180-189

• PubMed: 8306960 


• PubMed Abstract: 
  

The basic/helix-loop-helix/leucine zipper (b/HLH/Z) transcription factor upstream stimulatory factor (USF) and its isolated DNA binding domain undergo a random coil to alpha-helix folding transition on recognizing their cognate DNA. The USF b/HLH cocrystal structure resembles the structure of the b/HLH/Z domain of the homologous protein Max and reveals (i) that the truncated, b/HLH DNA binding domain homodimerizes, forming a parallel, left-handed four-helix bundle, and (ii) that the basic region becomes alpha-helical on binding to the major groove of the DNA sequence CACGTG. Hydrodynamic measurements show that the b/HLH/Z DNA binding domain of USF exists as a bivalent homotetramer. This tetramer forms at the USF physiological intranuclear concentration, and depends on the integrity of the leucine zipper motif. The ability to bind simultaneously to two independent sites suggests a role in DNA looping for the b/HLH/Z and Myc-related families of eukaryotic transcription factors.

---

Organizational Affiliation: 

Laboratories of Molecular Biophysics, Rockefeller University, New York, NY 10021.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 3
Molecule	Chains	Sequence Length	Organism	Details
PROTEIN (UPSTREAM STIMULATORY FACTOR)	A, B	65	Homo sapiens	Mutation(s): 2  Gene Names: USF1 (BHLHB11, USF)
Find proteins for P22415 (Homo sapiens) Go to Gene View: USF1 Go to UniProtKB:  P22415

Entity ID: 1
Molecule	Chains	Length	Organism
DNA (5'-D(*CP*AP*CP*CP*CP*GP*GP*TP*CP*AP*CP*GP*TP*GP*GP*CP*C P*TP*AP*CP*A)-3')	C	21	N/A

Entity ID: 2
Molecule	Chains	Length	Organism
DNA (5'-D(*GP*TP*GP*TP*AP*GP*GP*CP*CP*AP*CP*GP*TP*GP*AP*CP*C P*GP*GP*GP*T)-3')	D	21	N/A

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.9 Å
• R-Value Work: 0.236 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length (Å)	Angle (°)
a = 136.600	α = 90.00
b = 54.700	β = 90.00
c = 44.400	γ = 90.00

Software Package:

Software Name	Purpose
X-PLOR	refinement
X-PLOR	model building
SCALEPACK	data scaling
DENZO	data reduction
X-PLOR	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1997-03-15 
• Released Date: 1997-09-17 
• Deposition Author(s): Ferre-D'Amare, A.R., Pognonec, P., Roeder, R.G., Burley, S.K.

Revision History 

• Version 1.0: 1997-09-17
  Type: Initial release
• Version 1.1: 2008-05-22
  Type: Version format compliance
• Version 1.2: 2011-07-13
  Type: Version format compliance