Joël Nargeot - Academia.edu (original) (raw)
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Papers by Joël Nargeot
FEBS Letters, 1996
Hypokalaemic periodic paralysis (HypoPP) is an autosomal dominant muscle disease which has been l... more Hypokalaemic periodic paralysis (HypoPP) is an autosomal dominant muscle disease which has been linked to point mutations in the skeletal muscle L-type calcium channel cq subunit (~ls). Here, we have introduced one of the point mutations causing HypoPP (R528H) into cDNA of the rabbit Cqs. Expression of either the wild-type ~tsor the mutant R528H Cqs (~ls-Rszsn) subunits was obtained in mouse Ltk cells using a selectable expression vector. The Cqs-Rs28n subunit led to the expression of functional L-type Ca z+ channels. Corresponding whole-cell Ba 2+ currents exhibit very slow activation and inactivation kinetics, typical for recombinant skeletal Ca 2+ channel currents. Voltage-dependent activation and inactivation properties were similar for ~ts-and ~IS-RS2Sn, as well as their sensitivity to the dihydropyridine agonist Bay K 8644. Differences in Cqs-and ~ls-Rs28n-directed channels reside in the Ba 2+ current density, which was significantly reduced 3.2 fold in cells expressing ~lS-RS2Sn It was concluded that the R528H mutation of Cqs results in minor differences in the electrophysiological properties but significantly reduces the whole-cell Ca z÷ channel current in its amplitude.
FEBS Letters, 1996
Hypokalaemic periodic paralysis (HypoPP) is an autosomal dominant muscle disease which has been l... more Hypokalaemic periodic paralysis (HypoPP) is an autosomal dominant muscle disease which has been linked to point mutations in the skeletal muscle L-type calcium channel cq subunit (~ls). Here, we have introduced one of the point mutations causing HypoPP (R528H) into cDNA of the rabbit Cqs. Expression of either the wild-type ~tsor the mutant R528H Cqs (~ls-Rszsn) subunits was obtained in mouse Ltk cells using a selectable expression vector. The Cqs-Rs28n subunit led to the expression of functional L-type Ca z+ channels. Corresponding whole-cell Ba 2+ currents exhibit very slow activation and inactivation kinetics, typical for recombinant skeletal Ca 2+ channel currents. Voltage-dependent activation and inactivation properties were similar for ~ts-and ~IS-RS2Sn, as well as their sensitivity to the dihydropyridine agonist Bay K 8644. Differences in Cqs-and ~ls-Rs28n-directed channels reside in the Ba 2+ current density, which was significantly reduced 3.2 fold in cells expressing ~lS-RS2Sn It was concluded that the R528H mutation of Cqs results in minor differences in the electrophysiological properties but significantly reduces the whole-cell Ca z÷ channel current in its amplitude.