Solubilization, characterization and photoaffinity labeling of the mitochondrial dihydropyridine receptor from bovine adrenal medulla.
1. The mitochondrial dihydropyridine receptor was solubilized with Chaps at a detergent/protein ratio of 2.5, during 45 min at 4 degrees C. 2. From the rate constants of association (8.10 +/- 0.25 x 10(4) M-1 min-1) and dissociation (0.022 +/- 0.001 min-1) a Kd of 275 nM was calculated, while from saturation experiments a Kd of 270 +/- 30 nM and a density of receptors of 106 +/- 9 pmol/mg protein was obtained. 4. The solubilized receptors are heat-resistant, sensitive to the trypsin and to the reduction of disulfide bonds. 5. In native membranes, a polypeptide of 50 kDa was specifically photolabelled with [3H]Azidopine.
Hidalgo
M J
MJ
Departamento de Neuroquímica, Universidad de Alicante, Spain.
Gutierrez
L M
LM
Palmero
M
M
Ballesta
J J
JJ
Reig
J A
JA
Viniegra
S
S
D000313:Adrenal Medulla / Q000737:chemistry* / Q000648:ultrastructure; D000818:Animals; D020746:Calcium Channels, L-Type; D002417:Cattle; D008928:Mitochondria / Q000737:chemistry*; D008970:Molecular Weight; D009124:Muscle Proteins / Q000737:chemistry*; D012995:Solubility; D014316:Tritium
D020746:Calcium Channels, L-Type; D009124:Muscle Proteins; D014316:Tritium