Summary information and primary citation
- PDB-id
-
1an4;
DSSR-derived features in text and
JSON formats; DNAproDB
- Class
- transcription-DNA
- Method
- X-ray (2.9 Å)
- Summary
- Structure and function of the b-hlh-z domain of
usf
- Reference
-
Ferre-D'Amare AR, Pognonec P, Roeder RG, Burley SK
(1994): "Structure
and function of the b/HLH/Z domain of USF." EMBO
J., 13, 180-189.
- 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.
