Calcium channelopathies

Published on January 31, 2022   46 min

Other Talks in the Series: Calcium Signaling II

This is a presentation on "Calcium Channelopathies". My name is David Friel from the Department of Neurosciences at Case Western Reserve University. My research focuses on calcium and electrical signaling in excitable cells and the impact of calcium channel mutations on electrophysiological properties of cells involved in cerebellar motor control.
In this presentation, we'll start by defining what we mean by channelopathies and present a conceptual framework for discussing them that is based on the central dogma of molecular biology. We will then discuss classification of channelopathies based on clinical syndrome and based on the ion channels that are defective. This will be followed by a discussion of voltage-gated calcium channel, which will be the focus of our discussion of calcium channelopathies. We will then present several examples of human calcium channelopathies that span the range of phenotypic complexity and illustrate general concepts that are relevant to other channelopathies. This will be followed by a summary of the main points in the presentation.
Let's start by defining what we mean by channelopathies. Channelopathies are diseases that result from defects in ion channel function. Channelopathies can be classified based on whether they are inherited or acquired. But for our purposes, it will be more useful to classify them based on whether they result from genetic versus non genetic causes. Genetic causes involve modification of genes that encode channel proteins, which either occur in germ cells and can be passed on to offspring or in somatic cells as a result of de novo mutations. Non-genetic causes include actions of drugs or toxins or autoimmune attack of ion channels. While the focus of this presentation will be on channelopathies that result from modification of channel genes, two examples of channel disorders that result from non-genetic causes are cardiac arrhythmias such as long QT syndrome, which can result as a side effect of some pharmacological agents used to treat other disorders that alter the activity of ion channels important for normal cardiac function. And Lambert-Eaton myasthenic syndrome, an autoimmune disease characterized by lots of presynaptic calcium channels at the neuromuscular junction leading to muscle weakness.