Sandbox 213: Difference between revisions
No edit summary |
No edit summary |
||
| Line 62: | Line 62: | ||
Calmodulin uses a linear sequence of 12 amino acids to bind Ca<sup>2+</sup>. | Calmodulin uses a linear sequence of 12 amino acids to bind Ca<sup>2+</sup>. | ||
Binding of Ca<sup>2+</sup> to the four sites induces a large conformational change causing the terminal helices to expose hydrophobic surfaces and also a long central α-helical segment. Ca<sup>2+</sup>-bound calmodulin binds to its targets with high affinity (K<sub>D</sub>≈10<sup>−9</sup> mol.L<sup>−1</sup>). | Binding of Ca<sup>2+</sup> to the four sites induces a large conformational change causing the terminal helices to expose hydrophobic surfaces and also a long central α-helical segment. Ca<sup>2+</sup>-bound calmodulin binds to its targets with high affinity (K<sub>D</sub>≈10<sup>−9</sup> mol.L<sup>−1</sup>)<ref name="Najl V Valeyev1, Declan G Bates1, Pat Heslop-Harrison1,2, Ian Postlethwaite1 and Nikolay V Kotov. Elucidating the mechanisms of cooperative calcium-calmodulin interactions: a structural systems biology approach.BMC Systems Biology 2008, 2:48 doi:[[10.1186/1752-0509-2-48]]"/>. | ||
| Line 76: | Line 77: | ||
The N-terminal and C-terminal regions approach each other and by their hydrophobic surfaces bind to it, rather like two hands holding a rope. | The N-terminal and C-terminal regions approach each other and by their hydrophobic surfaces bind to it, rather like two hands holding a rope. | ||
This encourages the target sequence to adopt an α-helical arrangement so that it occupies the center of a hydrophobic tunnel. | This encourages the target sequence to adopt an α-helical arrangement so that it occupies the center of a hydrophobic tunnel. | ||
The consequence of this interaction is a conformational change in the target, a state that persists only as long as the Ca<sup>2+</sup> concentration remains high. | The consequence of this interaction is a conformational change in the target, a state that persists only as long as the Ca<sup>2+</sup> concentration remains high <ref name="Najl V Valeyev1, Declan G Bates1, Pat Heslop-Harrison1,2, Ian Postlethwaite1 and Nikolay V Kotov. Elucidating the mechanisms of cooperative calcium-calmodulin interactions: a structural systems biology approach.BMC Systems Biology 2008, 2:48 doi:[[10.1186/1752-0509-2-48]]"/>. | ||
| Line 118: | Line 120: | ||
<ref group="xtra"> doi: 10.1074/jbc.M109.013326</ref><references group="xtra"/> | <ref group="xtra"> doi: 10.1074/jbc.M109.013326</ref><references group="xtra"/> | ||
<ref group="xtra">PMID:17151196</ref><references group="xtra"/> | |||
<ref group="xtra">PMID:15194112</ref><references group="xtra"/> | |||
<ref group="xtra">PMID:14527397</ref><references group="xtra"/> | <ref group="xtra">PMID:14527397</ref><references group="xtra"/> | ||
| Line 123: | Line 129: | ||
<ref group="xtra">doi:10.1002/prot.22317</ref><references group="xtra"/> | <ref group="xtra">doi:10.1002/prot.22317</ref><references group="xtra"/> | ||
=Proteopedia page contributors and editor= | =Proteopedia page contributors and editor= | ||
Tonazzini Saphia, Planchenault Charlène | Tonazzini Saphia, Planchenault Charlène | ||