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1m46
From Proteopedia
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CRYSTAL STRUCTURE OF MLC1P BOUND TO IQ4 OF MYO2P, A CLASS V MYOSIN
Overview
IQ motifs are widespread in nature. Mlc1p is a calmodulin-like myosin, light chain that binds to IQ motifs of a class V myosin, Myo2p, and an, IQGAP-related protein, Iqg1p, playing a role in polarized growth and, cytokinesis in Saccharomyces cerevisiae. The crystal structures of Mlc1p, bound to IQ2 and IQ4 of Myo2p differ dramatically. When bound to IQ2, Mlc1p adopts a compact conformation in which both the N- and C-lobes, interact with the IQ motif. However, in the complex with IQ4, the N-lobe, no longer interacts with the IQ motif, resulting in an extended, conformation of Mlc1p. The two light chain structures relate to two, distinct subfamilies of IQ motifs, one of which does not interact with the, N-lobes of calmodulin-like light chains. The correlation between light, chain structure and IQ sequence is demonstrated further by sedimentation, velocity analysis of complexes of Mlc1p with IQ motifs from Myo2p and, Iqg1p. The resulting 'free' N-lobes of myosin light chains in the extended, conformation could mediate the formation of ternary complexes during, protein localization and/or partner recruitment.
About this Structure
1M46 is a Protein complex structure of sequences from Saccharomyces cerevisiae. Full crystallographic information is available from OCA.
Reference
Two distinct myosin light chain structures are induced by specific variations within the bound IQ motifs-functional implications., Terrak M, Wu G, Stafford WF, Lu RC, Dominguez R, EMBO J. 2003 Feb 3;22(3):362-71. PMID:12554638
Page seeded by OCA on Tue Nov 20 21:08:04 2007
