Summary information and primary citation

PDB-id
1hbx; SNAP-derived features in text and JSON formats; DNAproDB
Class
gene regulation
Method
X-ray (3.15 Å)
Summary
Ternary complex of sap-1 and srf with specific sre DNA
Reference
Hassler M, Richmond TJ (2001): "The B-Box Dominates Sap-1/Srf Interactions in the Structure of the Ternary Complex." Embo J., 20, 3018. doi: 10.1093/EMBOJ/20.12.3018.
Abstract
The serum response element (SRE) is found in several immediate-early gene promoters. This DNA sequence is necessary and sufficient for rapid transcriptional induction of the human c-fos proto-oncogene in response to stimuli external to the cell. Full activation of the SRE requires the cooperative binding of a ternary complex factor (TCF) and serum response factor (SRF) to their specific DNA sites. The X-ray structure of the human SAP-1-SRF-SRE DNA ternary complex was determined (Protein Data Bank code 1hbx). It shows SAP-1 TCF bound to SRF through interactions between the SAP-1 B-box and SRF MADS domain in addition to contacts between their respective DNA-binding motifs. The SAP-1 B-box is part of a flexible linker of which 21 amino acids become ordered upon ternary complex formation. Comparison with a similar region from the yeast MATalpha2-MCM1-DNA complex suggests a common binding motif through which MADS-box proteins may interact with additional factors such as Fli-1.

Cartoon-block schematics in six views (download the tarball)

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