1omr
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non-myristoylated wild-type bovine recoverin with calcium bound to EF-hand 3
OverviewOverview
Recoverin is a Ca2+-regulated signal transduction modulator found in, vertebrate retina that has been shown to undergo dramatic conformational, changes upon Ca2+ binding to its two functional EF-hand motifs. To, elucidate the differential impact of the N-terminal myristoylation as well, as occupation of the two Ca2+ binding sites on recoverin structure and, function, we have investigated a non-myristoylated E85Q mutant exhibiting, virtually no Ca2+ binding to EF-2. Crystal structures of the mutant, protein as well as the non-myristoylated wild-type have been determined., Although the non-myristoylated E85Q mutant does not display any functional, activity, its three-dimensional structure in the presence of Ca2+, resembles the myristoylated wild-type with two Ca2+ but is quite, dissimilar from the myristoylated E85Q mutant. We conclude that the, N-terminal myristoyl modification significantly stabilizes the, conformation of the Ca2+-free protein (i.e. the T conformation) during the, stepwise transition toward the fully Ca2+-occupied state. On the basis of, these observations, a refined model for the role of the myristoyl group as, an intrinsic allosteric modulator is proposed.
About this StructureAbout this Structure
1OMR is a Single protein structure of sequence from Bos taurus with CA as ligand. Full crystallographic information is available from OCA.
ReferenceReference
Impact of N-terminal myristoylation on the Ca2+-dependent conformational transition in recoverin., Weiergraber OH, Senin II, Philippov PP, Granzin J, Koch KW, J Biol Chem. 2003 Jun 20;278(25):22972-9. Epub 2003 Apr 9. PMID:12686556
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