SERCA - IC50 for Cisplatin
Ca2+-transport in SERCA is triggered by ATP hydrolysis. Using ATP concentration jumps, the authors determined the IC50 of SERCA inhibition by cisplatin
Background and Assay Description:
We have performed 100 µM ATP concentration jumps in presence of 10 μM free Ca2+ to activate SERCA. By adding different concentrations of cisplatin into the measurement solutions, SERCA activation leads to a reduced current. We have plotted the normalized charges (QNorm) as a function of cisplatin concentration. The charges are normalized with reference to the maximum charge attained in the absence of cisplatin (control measurement). The solid line represents the fitting curve to the ATP-induced charges (IC50 = 1.3 ± 0.1 µM). The error bars represent the S.E. of three independent measurements.
Impact of the data:
We found that 5 µM cisplatin almost abolishes the ATP-induced peak current and the related charge displacement, thereby indicating that cisplatin strongly interferes with ATP-dependent calcium translocation. The determined IC50 value of 1.3 µM indicates that cisplatin acts as a high affinity SERCA inhibitor.
Author: Francesco Tadini-Buoninsegni, University of Florence
Target: SERCA - Sarco/Endoplasmic Reticulum Calcium-ATPase
Family/Type: p2-type ATPase
Mode of transport: ATP-driven Ca2+ transport
Sample: Purified sarcoplasmic reticulum vesicles from the hind leg muscles of New Zealand White rabbits
Platform: SURFE²R One, a predecessor model of the SURFE²R N1