Protein
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Species
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Information
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Comment
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Submitted By
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Validated By
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calmodulin
isoform 1
the main isoform, and the only isoform found in most species
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no species information |
The conformational change between apo and four calcium ions bound states involves:- The conformational change is a reorganization of existing secondary structural elements in each domain.
Upon calcium-binding, the bottoms of helices I and II swing apart, while the tops pinch together; a similar change is observed for helices III and IV. The interface between helcies II and IV is completely disrupted, as the two helices move apart along their entire lengths. The interfaces beteen helices I and IV and between helices II and III are not much affected by calcium-binding.
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Melanie R. Nelson
The Scripps Research Institute, Department of Molecular Biology
mnelson@scripps.edu
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Melanie R. Nelson
mnelson@scripps.edu
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myosin essential light chain
lower animal isoform
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no species information |
The conformational change between one calcium ion bound and one calcium ion and target peptide bound states involves:- There is no structure of ELC not bound to the heavy chain. However, in the structure of the myosin light chains complexed to the heavy chain, ELC-N is in the closed conformation and ELC-C is in the semi-open conformation. ELC-N can be used as a model for closed conformation ELC-C, allowing a determination of the conformational changes expected to be induced by heavy chain binding if ELC-C adopts a closed conformation in tyhe absence of the heavy chain.
The differences between these conformations are confined to the reorganization of existing secondary structural elements.
The closed conformation is very similar to that seen in apo calmodulin. The semi-open conformation is a distinct conformation, and not merely midway between the closed and open conformation. In this conformation: Helices II and III are drawn together at the bottoms; Helices I and II are pried apart; Helices III and IV "scissor" apart, with a pivot point in the top half of the interface.
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Melanie R. Nelson
The Scripps Research Institute, Department of Molecular Biology
mnelson@scripps.edu
|
Melanie R. Nelson
mnelson@scripps.edu
|
troponin C
skeletal isoform
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no species information |
The conformational change between apo and four calcium ions bound states involves:- The conformational change is essentially the same as seen in calmodulin, and consists of a reorganization of existing secondary structural elements in each domain.
Upon calcium-binding, the bottoms of helices I and II swing apart, while the tops pinch together; a similar change is observed for helices III and IV. The interface between helcies II and IV is completely disrupted, as the two helices move apart along their entire lengths. The interfaces beteen helices I and IV and between helices II and III are not much affected by calcium-binding.
|
|
Melanie R. Nelson
The Scripps Research Institute, Department of Molecular Biology
mnelson@scripps.edu
|
Melanie R. Nelson
mnelson@scripps.edu
|
