Calcium channelopathies.
Intracellular calcium ([Ca2+]i) is highly regulated in eukaryotic cells. The free [Ca2+]i is approximately four orders of magnitude less than that in the extracellular environment. It is, therefore, an electrochemical gradient favoring Ca2+ entry, and transient cellular activation increasing Ca2+ permeability will lead to a transient increase in [Ca2+]i. These transient rises of [Ca2+]i trigger or regulate diverse intracellular events, including metabolic processes, muscle contraction, secretion of hormones and neurotransmitters, cell differentiation, and gene expression. Hence, changes in [Ca2+]i act as a second messenger system coordinating modifications in the external environment with intracellular processes. Notably, information on the molecular genetics of the membrane channels responsible for the influx of Ca2+ ions has led to the discovery that mutations in these proteins are linked to human disease. Ca2+ channel dysfunction is now known to be the basis for several neurological and muscle disorders such as migraine, ataxia, and periodic paralysis. In contrast to other types of genetic diseases, Ca2+ channelopathies can be studied with precision by electrophysiological methods, and in some cases, the results have been highly rewarding with a biophysical phenotype that correlates with the ultimate clinical phenotype. This review outlines recent advances in genetic, molecular, and pathophysiological aspects of human Ca2+ channelopathies.
Felix
Ricardo
R
Department of Cell Biology, Center for Research and Advanced Studies, National Polytechnic Institute (Cinvestav-IPN), Mexico City, Mexico. rfelix@fisio.cinvestav.mx
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D015220:Calcium Channels / Q000737:chemistry / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D053447:Channelopathies / Q000235:genetics / Q000503:physiopathology*; D004195:Disease Models, Animal; D040181:Genetic Diseases, X-Linked / Q000235:genetics / Q000503:physiopathology; D020022:Genetic Predisposition to Disease; D006801:Humans; D020514:Hypokalemic Periodic Paralysis / Q000235:genetics / Q000503:physiopathology; D008305:Malignant Hyperthermia / Q000235:genetics / Q000503:physiopathology; D009154:Mutation; D009755:Night Blindness / Q000235:genetics / Q000503:physiopathology; D010802:Phylogeny; D011487:Protein Conformation; D020754:Spinocerebellar Ataxias / Q000235:genetics / Q000503:physiopathology; D013132:Spinocerebellar Degenerations / Q000235:genetics / Q000503:physiopathology
D015220:Calcium Channels; D002118:Calcium