3inq | pdb_00003inq
Crystal structure of BCL-XL in complex with W1191542
Structural highlights
Function[B2CL1_HUMAN] Potent inhibitor of cell death. Inhibits activation of caspases (By similarity). Appears to regulate cell death by blocking the voltage-dependent anion channel (VDAC) by binding to it and preventing the release of the caspase activator, CYC1, from the mitochondrial membrane. Also acts as a regulator of G2 checkpoint and progression to cytokinesis during mitosis.[1] [2] Isoform Bcl-X(S) promotes apoptosis.[3] [4] 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 PubMedAntagonists of anti-apoptotic Bcl-2 family members hold promise as cancer therapeutics. Apoptosis is triggered when a peptide containing a BH3 motif or a small molecule BH3 peptidomimetic, such as ABT 737, binds to the relevant Bcl-2 family members. ABT-737 is an antagonist of Bcl-2, Bcl-x(L), and Bcl-w but not of Mcl-1. Here we describe new structures of mutant BH3 peptides bound to Bcl-x(L) and Mcl-1. These structures suggested a rationale for the failure of ABT-737 to bind Mcl-1, but a designed variant of ABT-737 failed to acquire binding affinity for Mcl-1. Rather, it was selective for Bcl-x(L), a result attributable in part to significant backbone refolding and movements of helical segments in its ligand binding site. To date there are few reported crystal structures of organic ligands in complex with their pro-survival protein targets. Our structure of this new organic ligand provided insights into the structural transitions that occur within the BH3 binding groove, highlighting significant differences in the structural properties of members of the Bcl-2 pro-survival protein family. Such differences are likely to influence and be important in the quest for compounds capable of selectively antagonizing the different family members. Conformational changes in Bcl-2 pro-survival proteins determine their capacity to bind ligands.,Lee EF, Czabotar PE, Yang H, Sleebs BE, Lessene G, Colman PM, Smith BJ, Fairlie WD J Biol Chem. 2009 Oct 30;284(44):30508-17. Epub 2009 Sep 2. PMID:19726685[5] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
| ||||||||||||||||||||
