7k02

From Proteopedia

The crystal structure of a BAK dimer activated by detergent

Structural highlights

7k02 is a 6 chain structure with sequence from Homo sapiens. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 3.4Å
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

BAK_HUMAN In the presence of an appropriate stimulus, accelerates programmed cell death by binding to, and antagonizing the anti-apoptotic action of BCL2 or its adenovirus homolog E1B 19k protein. Low micromolar levels of zinc ions inhibit the promotion of apoptosis.^[1] ^[2]

Publication Abstract from PubMed

A body of data supports the existence of core (alpha2-alpha5) dimers of BAK and BAX in the oligomeric, membrane-perturbing conformation of these essential apoptotic effector molecules. Molecular structures for these dimers have only been captured for truncated constructs encompassing the core domain alone. Here, we report a crystal structure of BAK alpha2-alpha8 dimers (i.e., minus its flexible N-terminal helix and membrane-anchoring C-terminal segment) that has been obtained through the activation of monomeric BAK with the detergent C12E8. Core dimers are evident, linked through the crystal by contacts via latch (alpha6-alpha8) domains. This crystal structure shows activated BAK dimers with the extended latch domain present. Our data provide direct evidence for the conformational change converting BAK from inert monomer to the functional dimer that destroys mitochondrial integrity. This dimer is the smallest functional unit for recombinant BAK or BAX described so far.

Structure of detergent-activated BAK dimers derived from the inert monomer.,Birkinshaw RW, Iyer S, Lio D, Luo CS, Brouwer JM, Miller MS, Robin AY, Uren RT, Dewson G, Kluck RM, Colman PM, Czabotar PE Mol Cell. 2021 Mar 23. pii: S1097-2765(21)00182-9. doi:, 10.1016/j.molcel.2021.03.014. PMID:33794146^[3]

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

References

↑ Chittenden T, Flemington C, Houghton AB, Ebb RG, Gallo GJ, Elangovan B, Chinnadurai G, Lutz RJ. A conserved domain in Bak, distinct from BH1 and BH2, mediates cell death and protein binding functions. EMBO J. 1995 Nov 15;14(22):5589-96. PMID:8521816
↑ Moldoveanu T, Liu Q, Tocilj A, Watson M, Shore G, Gehring K. The X-ray structure of a BAK homodimer reveals an inhibitory zinc binding site. Mol Cell. 2006 Dec 8;24(5):677-88. PMID:17157251 doi:10.1016/j.molcel.2006.10.014
↑ Birkinshaw RW, Iyer S, Lio D, Luo CS, Brouwer JM, Miller MS, Robin AY, Uren RT, Dewson G, Kluck RM, Colman PM, Czabotar PE. Structure of detergent-activated BAK dimers derived from the inert monomer. Mol Cell. 2021 Mar 23. pii: S1097-2765(21)00182-9. doi:, 10.1016/j.molcel.2021.03.014. PMID:33794146 doi:http://dx.doi.org/10.1016/j.molcel.2021.03.014