TRANSCRIPTIONAL CHANNELOPATHIES: AN EMERGING CLASS OF DISORDERS.

Two types of channelopathy are now well recognized: genetic, in which ion channels function abnormally or fail to function as a result of mutations, and autoimmune, in which antibodies perturb channel function. Recent studies have provided growing evidence for the existence of a third type ? transcriptional channelopathies ? which result from changes in the expression of non-mutated channel genes. A well-studied example is peripheral nerve injury, which causes spinal sensory neurons to turn off some active sodium channel genes and turn on others that were previously silent, a set of changes that can result in hyperexcitability of these cells. Recent studies have also shown upregulated expression of sensory-neuron-specific sodium channels in Purkinje cells, indicating that a transcriptional channelopathy might perturb cerebellar function in multiple sclerosis. It is probable that we will soon recognize further disorders that are characterized by dysregulation of channel gene expression in neurons. A better understanding of transcriptional channelopathies might provide us with new opportunities to treat these disorders. [ABSTRACT FROM AUTHOR]