Posted by lettsscience on September 15, 2012 · 6 Comments
In this post I continue my series on the omega current by discussing how a mutation that removes a charged group from the voltage-sensor domain (VSD) would be highly destabilizing and disruptive. The omega current is a leak current that passes through the VSD of mutated voltage-gated cation channels. In some cases, the mutated channels … Continue reading →
Filed under Biochemistry, Biophysics, Hv, Ion channels, Opinion, Review, Science, Voltage gating · Tagged with 6TM channels, gated ion channels, ion selectivity, molecular mechanism, omega current, omega pore, Opinion, protein architechture, protein structure function, S4 helix, voltage gating, voltage sensor domain, voltage-gated cation channels
Posted by lettsscience on August 20, 2012 · 4 Comments
In this post I will be continuing my series on the omega current. The omega current is a leak current that passes through the voltage-sensor domain (VSD) of mutated voltage-gated cation channels. Mutation of the VSD S4 helix can reveal a cryptic pore that allows ions (H+, Li+, K+, Rb+ and even guanidinium) to cross … Continue reading →
Filed under Biochemistry, Biophysics, Ion channels, Opinion, Physiology, Review, Science, Voltage gating · Tagged with 6TM channels, Benign familial neonatal epilepsy, channelopathy, hypkalemic periodic paralysis, ion channels, omega current, omega pore, Opinion, Peripheral nerve hyperexcitability, protein architechture, protein structure function, Review, S4 helix, science, voltage gating, voltage sensor domain, voltage-gated cation channels
Posted by lettsscience on July 24, 2012 · 4 Comments
Mutation of voltage-sensor domains (VSDs) can sometimes lead to ions leaking across the membrane through the VSDs themselves. Ion conduction through the mutated VSD of the Shaker Kv channel was coined the “omega current” by Tombola, Pathak and Isacoff (Tombola et al., 2005). Many different mutations have been identified that result in current leaking through the VSDs of … Continue reading →
Filed under Biochemistry, Biophysics, Hv, Ion channels, Opinion, Physiology, Review, Science, Voltage gating · Tagged with 6TM channels, gated ion channels, ion channels, omega current, omega pore, Opinion, potassium channels, protein structure function, science, voltage sensor domain, voltage-gated cation channels, VSD