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1hbx
From Proteopedia
TERNARY COMPLEX OF SAP-1 AND SRF WITH SPECIFIC SRE DNA
Overview
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.
About this Structure
1HBX is a Protein complex structure of sequences from Homo sapiens. Full crystallographic information is available from OCA.
Reference
The B-box dominates SAP-1-SRF interactions in the structure of the ternary complex., Hassler M, Richmond TJ, EMBO J. 2001 Jun 15;20(12):3018-28. PMID:11406578 Page seeded by OCA on Fri May 2 18:40:44 2008
