3fdo

From Proteopedia
Jump to navigation Jump to search

Structure of human MDMX in complex with high affinity peptideStructure of human MDMX in complex with high affinity peptide

Structural highlights

3fdo is a 2 chain structure with sequence from Homo sapiens and Synthetic construct. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:X-ray diffraction, Resolution 1.4Å
Ligands:
Resources:FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

MDM4_HUMAN Inhibits p53/TP53- and TP73/p73-mediated cell cycle arrest and apoptosis by binding its transcriptional activation domain. Inhibits degradation of MDM2. Can reverse MDM2-targeted degradation of TP53 while maintaining suppression of TP53 transactivation and apoptotic functions.[1] [2]

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

The Mdm2 and Mdmx proteins are the principal negative regulators of the p53 tumor suppressor. Reactivation of p53 activity by disrupting the Mdm2/Mdmx-p53 interactions offers new possibilities for anticancer therapeutics. Here, we present crystal structures of two complexes, a p53-like mutant peptide with the N-terminal domains of Mdm2 and Mdmx, respectively. The structures reveal that the p53 mutant peptide (amino acid sequence: LTFEHYWAQLTS) assumes virtually identical conformations in both complexes despite the different shapes of the p53-binding pockets in these two proteins, has a more extended helical nature compared to the Mdm2-bound wild-type p53 peptide, and does not disturb the native folds of Mdm2 or Mdmx. The extension of the helical structure in the mutant p53 peptide greatly improves its binding to Mdm2 and Mdmx. The fluorescence polarization assay that we have developed using this peptide indicates the affinities towards Mdm2 of 3.6 nM and for Mdmx of 6.1 nM, compared to the low micromolar binding of a similar length wild-type p53 peptide to Mdm2/Mdmx. Our assay does not require expensive non-native amino acids, and allows measurements of the interaction with both Mdm2 and Mdmx in identical conditions-without modification of experimental conditions or setups between the two proteins. The structural information presented here, coupled with the robust fluorescence polarization assay, should enable development of a simple pharmacophore model of cross-selective Mdm2-Mdmx/p53 inhibitors.

High affinity interaction of the p53 peptide-analogue with human Mdm2 and Mdmx.,Czarna A, Popowicz GM, Pecak A, Wolf S, Dubin G, Holak TA Cell Cycle. 2009 Apr 16;8(8). PMID:19305137[3]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

See Also

References

  1. Chen L, Gilkes DM, Pan Y, Lane WS, Chen J. ATM and Chk2-dependent phosphorylation of MDMX contribute to p53 activation after DNA damage. EMBO J. 2005 Oct 5;24(19):3411-22. Epub 2005 Sep 15. PMID:16163388 doi:10.1038/sj.emboj.7600812
  2. Jin Y, Dai MS, Lu SZ, Xu Y, Luo Z, Zhao Y, Lu H. 14-3-3gamma binds to MDMX that is phosphorylated by UV-activated Chk1, resulting in p53 activation. EMBO J. 2006 Mar 22;25(6):1207-18. Epub 2006 Mar 2. PMID:16511572 doi:10.1038/sj.emboj.7601010
  3. Czarna A, Popowicz GM, Pecak A, Wolf S, Dubin G, Holak TA. High affinity interaction of the p53 peptide-analogue with human Mdm2 and Mdmx. Cell Cycle. 2009 Apr 16;8(8). PMID:19305137

3fdo, resolution 1.40Å

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA