Journal ArticleDOI
Structure and regulation of voltage-gated Ca2+ channels.
TLDR
The distinct structures and patterns of regulation of these three families of Ca(2+) channels provide a flexible array of Ca('s 2+) entry pathways in response to changes in membrane potential and a range of possibilities for regulation of Ca (2+) entry by second messenger pathways and interacting proteins.Abstract:
Voltage-gated Ca(2+) channels mediate Ca(2+) entry into cells in response to membrane depolarization. Electrophysiological studies reveal different Ca(2+) currents designated L-, N-, P-, Q-, R-, and T-type. The high-voltage-activated Ca(2+) channels that have been characterized biochemically are complexes of a pore-forming alpha1 subunit of approximately 190-250 kDa; a transmembrane, disulfide-linked complex of alpha2 and delta subunits; an intracellular beta subunit; and in some cases a transmembrane gamma subunit. Ten alpha1 subunits, four alpha2delta complexes, four beta subunits, and two gamma subunits are known. The Cav1 family of alpha1 subunits conduct L-type Ca(2+) currents, which initiate muscle contraction, endocrine secretion, and gene transcription, and are regulated primarily by second messenger-activated protein phosphorylation pathways. The Cav2 family of alpha1 subunits conduct N-type, P/Q-type, and R-type Ca(2+) currents, which initiate rapid synaptic transmission and are regulated primarily by direct interaction with G proteins and SNARE proteins and secondarily by protein phosphorylation. The Cav3 family of alpha1 subunits conduct T-type Ca(2+) currents, which are activated and inactivated more rapidly and at more negative membrane potentials than other Ca(2+) current types. The distinct structures and patterns of regulation of these three families of Ca(2+) channels provide a flexible array of Ca(2+) entry pathways in response to changes in membrane potential and a range of possibilities for regulation of Ca(2+) entry by second messenger pathways and interacting proteins.read more
Citations
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The Retinal Pigment Epithelium in Visual Function
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International Union of Pharmacology. XLVIII. Nomenclature and Structure-Function Relationships of Voltage-Gated Calcium Channels
TL;DR: The molecular relationships and physiological functions of these calcium channel proteins are presented and comprehensive information on their molecular, genetic, physiological, and pharmacological properties is provided.
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Photonic structures in biology
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Ca(V)1.2 calcium channel dysfunction causes a multisystem disorder including arrhythmia and autism.
Igor Splawski,Katherine W. Timothy,Leah M. Sharpe,Niels Decher,Pradeep Kumar,Raffaella Bloise,Carlo Napolitano,Peter J. Schwartz,Robert M. Joseph,Karen Condouris,Helen Tager-Flusberg,Silvia G. Priori,Michael C. Sanguinetti,Mark T. Keating +13 more
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References
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Three types of neuronal calcium channel with different calcium agonist sensitivity.
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The synaptic vesicle cycle: a cascade of protein–protein interactions
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Nomenclature of voltage-gated sodium channels.
Alan L. Goldin,Robert L. Barchi,John H. Caldwell,Franz Hofmann,James R. Howe,John C. Hunter,Roland G. Kallen,Gail Mandel,Miriam H. Meisler,Yoheved Berwald Netter,Masahara Noda,Michael M. Tamkun,Steven G. Waxman,John N. Wood,William A. Catterall +14 more
TL;DR: The present alphabetical nomenclature does not reveal the structural relationships among the α1 subunits of Ca2+ channels, but it is apparent that these two alphabeticals will overlap at α1L, which may not mediate an L-type Ca2- current and therefore may create confusion.
Journal ArticleDOI
Multiple types of neuronal calcium channels and their selective modulation
TL;DR: Efforts at classifying multiple types of Ca 2+ channels according to differences in their gating, ionic conductance and pharmacology are summarized.
Journal ArticleDOI
Primary structure of the receptor for calcium channel blockers from skeletal muscle
Tsutomu Tanabe,Hiroshi Takeshima,Atsushi Mikami,Veit Flockerzi,Hideo Takahashi,Kenji Kangawa,Masayasu Kojima,Hisayuki Matsuo,Tadaaki Hirose,Shosaku Numa +9 more
TL;DR: Structural and sequence similarities to the voltage-dependent sodium channel suggest that in the transverse tubule membrane of skeletal muscle the dihydropyridine receptor may act both as voltage sensor in excitation-contraction coupling and as a calcium channel.