Sandbox Reserved 820: Difference between revisions

Jump to navigation Jump to search
No edit summary
No edit summary
Line 35: Line 35:
== Calcium Binding ==  
== Calcium Binding ==  


Each monomere of CASQ2 can bind between <scene name='56/568018/Oligomere_and_ligand/12'>18 to 50 Ca2+</scene>. The Ca<sup>2+</sup> ions bind to two or more acidic amino acids like <scene name='56/568018/Oligomere_and_ligand/13'>Glutamate</scene> or <scene name='56/568018/Oligomere_and_ligand/15'>Aspartate</scene>. These amino acids are mainly oriented outside and in the C-terminal region. It had been shown that Ca<sup>2+</sup>ions mainly binds an Asp-rich region on the disordered C-terminal domain. <!-- METTRE DU VERT MAIS LE CT N'EST PAS DISPONIBLE cf: http://www.rcsb.org/pdb/explore/remediatedSequence.do?structureId=2VAF&bionumber=1 -->As CASQ2 form homooligomers, Ca<sup>2+</sup> can be bound in the electronegative pockets created by the front-to-front and back-to-back dimer interactions.<ref name="The asp-rich region at the carboxyl-terminus of calsequestrin binds to Ca<sup>2+</sup>‡ and interacts with triadin (Shin et al., 2000)">The Asp-rich region at the carboxyl-terminus of calsequestrin binds to Ca<sup>2+</sup> and interacts with triadin (Shin et al., 2000) http://www.sciencedirect.com/science/article/pii/S0014579300022468</ref>
Each monomere of CASQ2 can bind between <scene name='56/568018/Oligomere_and_ligand/12'>18 to 50 Ca2+</scene>. The Ca<sup>2+</sup> ions bind to two or more acidic amino acids like <scene name='56/568018/Oligomere_and_ligand/13'>Glutamate</scene> or <scene name='56/568018/Oligomere_and_ligand/15'>Aspartate</scene>. These amino acids are mainly oriented outside and in the C-terminal region. It had been shown that Ca<sup>2+</sup>ions mainly binds an Asp-rich region on the disordered C-terminal domain. <!-- METTRE DU VERT MAIS LE CT N'EST PAS DISPONIBLE cf: http://www.rcsb.org/pdb/explore/remediatedSequence.do?structureId=2VAF&bionumber=1 -->As CASQ2 form homooligomers, Ca<sup>2+</sup> can be bound in the electronegative pockets created by the <scene name='56/568018/Oligomere_and_ligand/16'>front-to-front</scene> and <scene name='56/568018/Oligomere_and_ligand/17'>back-to-back</scene> dimer interactions.<ref name="The asp-rich region at the carboxyl-terminus of calsequestrin binds to Ca<sup>2+</sup>‡ and interacts with triadin (Shin et al., 2000)">The Asp-rich region at the carboxyl-terminus of calsequestrin binds to Ca<sup>2+</sup> and interacts with triadin (Shin et al., 2000) http://www.sciencedirect.com/science/article/pii/S0014579300022468</ref>


CASQ2 can also bind other ions like Mg<sup>2+</sup> or H<sup>+</sup>. The affinity for Mg<sup>2+</sup> is lower than the affinity for Ca<sup>2+</sup> however the concentration of Ca<sup>2+</sup> decreases. When the pH is low, the calcium-binding capacity of CASQ2 decreases as H<sup>+</sup> ions occupy the acidic sites.<ref name="Calsequestrin and the calcium release channel of skeletal and cardiac muscle (Beard et Al., 2004)">PMID:15050380</ref>
CASQ2 can also bind other ions like Mg<sup>2+</sup> or H<sup>+</sup>. The affinity for Mg<sup>2+</sup> is lower than the affinity for Ca<sup>2+</sup> however the concentration of Ca<sup>2+</sup> decreases. When the pH is low, the calcium-binding capacity of CASQ2 decreases as H<sup>+</sup> ions occupy the acidic sites.<ref name="Calsequestrin and the calcium release channel of skeletal and cardiac muscle (Beard et Al., 2004)">PMID:15050380</ref>

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA, Marc-Antoine Jaques, Thomas Vuillemin, Stéphanie Gross