Characteristics of the Inhibitory Effect of Calmodulin on Specific [125i]omega-conotoxin GVIA Binding to Crude Membranes from Chick Brain
Overview
Affiliations
The characteristics of the inhibitory effect of calcium ion (Ca2+)/calmodulin (CaM) on specific [125I]-omega-conotoxin GVIA (125I-omega-CTX) binding and on the labeling of 125I-omega-CTX to crude membranes from chick brain were investigated. The inhibitory effect of Ca2+/CaM depended on the concentrations of free Ca2+ and CaM. The IC50 values for free Ca2+ and CaM were about 2.0 x 10(-8) M and 3.0 microg protein/ml, respectively. The inhibitory effect of Ca2+/CaM was attenuated by the CaM antagonists W-7, prenylamine and CaM-kinase II fragment (290-309), but not by the calcineurin inhibitor FK506. Ca2+/CaM also inhibited the labeling of a 135-kDa band (which was considered to be part of N-type Ca2+ channel alpha1 subunits) with 125I-omega-CTX using a cross-linker. These results suggest that Ca2+/CaM affects specific 125I-omega-CTX binding sites, probably N-type Ca2+ channel alpha1 subunits, in crude membranes from chick whole brain.
Spindle function in Xenopus oocytes involves possible nanodomain calcium signaling.
Li R, Leblanc J, He K, Liu X Mol Biol Cell. 2016; 27(21):3273-3283.
PMID: 27582389 PMC: 5170860. DOI: 10.1091/mbc.E16-05-0338.
Conotoxins that confer therapeutic possibilities.
Essack M, Bajic V, Archer J Mar Drugs. 2012; 10(6):1244-1265.
PMID: 22822370 PMC: 3397437. DOI: 10.3390/md10061244.
Wada T, Imanishi T, Kawaguchi A, Mori M, Mori Y, Imoto K Neurochem Res. 2005; 30(8):1045-54.
PMID: 16258854 DOI: 10.1007/s11064-005-7046-6.
Ichida S, Abe J, Komoike K, Imanishi T, Wada T, Masuko T Neurochem Res. 2005; 30(4):457-66.
PMID: 16076016 DOI: 10.1007/s11064-005-2681-5.
Ichida S, Abe J, Yu-an Z, Minami T, Wada T, Yazawa M Neurochem Res. 2003; 28(12):1813-8.
PMID: 14649722 DOI: 10.1023/a:1026163523145.