1hqv
From Proteopedia
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|PDB= 1hqv |SIZE=350|CAPTION= <scene name='initialview01'>1hqv</scene>, resolution 2.3Å | |PDB= 1hqv |SIZE=350|CAPTION= <scene name='initialview01'>1hqv</scene>, resolution 2.3Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand=CA:CALCIUM ION'>CA</scene> | + | |LIGAND= <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene> |
|ACTIVITY= | |ACTIVITY= | ||
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY= | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1hqv FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1hqv OCA], [http://www.ebi.ac.uk/pdbsum/1hqv PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1hqv RCSB]</span> | ||
}} | }} | ||
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[[Category: Jia, J.]] | [[Category: Jia, J.]] | ||
[[Category: Tarabykina, S.]] | [[Category: Tarabykina, S.]] | ||
| - | [[Category: CA]] | ||
[[Category: calcium binding protein]] | [[Category: calcium binding protein]] | ||
[[Category: penta-ef-hand protein]] | [[Category: penta-ef-hand protein]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 21:09:17 2008'' |
Revision as of 18:09, 30 March 2008
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| , resolution 2.3Å | |||||||
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| Ligands: | |||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
STRUCTURE OF APOPTOSIS-LINKED PROTEIN ALG-2
Overview
BACKGROUND: The Ca2+ binding apoptosis-linked gene-2 (ALG-2) protein acts as a proapoptotic factor in a variety of cell lines and is required either downstream or independently of caspases for apoptosis to occur. ALG-2 belongs to the penta-EF-hand (PEF) protein family and has two high-affinity and one low-affinity Ca2+ binding sites. Like other PEF proteins, its N terminus contains a Gly/Pro-rich segment. Ca2+ binding is required for the interaction with the target protein, ALG-2 interacting protein 1 (AIP1). RESULTS: We present the 2.3 A resolution crystal structure of Ca2+-Ioaded des1-20ALG-2 (aa 21-191), which was obtained by limited proteolysis of recombinant ALG-2 with elastase. The molecule contains eight alpha helices that fold into five EF-hands, and, similar to other members of this protein family, the molecule forms dimers. Ca2+ ions bind to EF1, EF3, and, surprisingly, to EF5. In the related proteins calpain and grancalcin, the EF5 does not bind Ca2+ and is thought to primarily facilitate dimerization. Most importantly, the conformation of des1-20ALG-2 is significantly different from that of calpain and grancalcin. This difference can be described as a rigid body rotation of EF1-2 relative to EF4-5 and the dimer interface, with a hinge within the EF3 loop. An electron density, which is interpreted as a hydrophobic Gly/Pro-rich decapeptide that is possibly derived from the cleaved N terminus, was found in a hydrophobic cleft between these two halves of the molecule. CONCLUSIONS: A different relative orientation of the N- and C-terminal halves of des1-20ALG-2 in the presence of Ca2+ and the peptide as compared to other Ca2+loaded PEF proteins changes substantially the shape of the molecule, exposing a hydrophobic patch on the surface for peptide binding and a large cleft near the dimer interface. We postulate that the binding of a Gly/ Pro-rich peptide in the presence of Ca2+ induces a conformational rearrangement in ALG-2, and that this mechanism is common to other PEF proteins.
About this Structure
1HQV is a Single protein structure of sequence from Mus musculus. Full crystallographic information is available from OCA.
Reference
Structure of apoptosis-linked protein ALG-2: insights into Ca2+-induced changes in penta-EF-hand proteins., Jia J, Tarabykina S, Hansen C, Berchtold M, Cygler M, Structure. 2001 Apr 4;9(4):267-75. PMID:11525164
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