9 results match your criteria homotetramer currents

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Differential PI(4,5)P sensitivities of TRPC4, C5 homomeric and TRPC1/4, C1/5 heteromeric channels.

Sci Rep 2019 02 12;9(1):1849. Epub 2019 Feb 12.

Department of Physiology, Seoul National University College of Medicine, Seoul, 03080, Republic of Korea.

Transient receptor potential canonical (TRPC) 4 and TRPC5 channels are modulated by the Gα-PLC pathway. Since phosphatidylinositol 4,5-bisphosphate (PI(4,5)P) maintains TRPC4 and TRPC5 channel function, the Gα-PLC pathway inhibits channel activity by depleting PI(4,5)P. Here we investigated the difference in PI(4,5)P sensitivity between homomeric and heteromeric TRPC channels. Read More

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February 2019

Src family protein tyrosine kinase regulates the basolateral K channel in the distal convoluted tubule (DCT) by phosphorylation of KCNJ10 protein.

J Biol Chem 2013 Sep 19;288(36):26135-26146. Epub 2013 Jul 19.

the Department of Pharmacology, New York Medical College, Valhalla, New York 10595,. Electronic address:

The loss of function of the basolateral K channels in the distal nephron causes electrolyte imbalance. The aim of this study is to examine the role of Src family protein tyrosine kinase (SFK) in regulating K channels in the basolateral membrane of the mouse initial distal convoluted tubule (DCT1). Single-channel recordings confirmed that the 40-picosiemen (pS) K channel was the only type of K channel in the basolateral membrane of DCT1. Read More

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September 2013

Cardiac calcium signalling pathologies associated with defective calmodulin regulation of type 2 ryanodine receptor.

J Physiol 2013 Sep 8;591(17):4287-99. Epub 2013 Jul 8.

M. Morad: Cardiac Signaling Center, 173 Ashley Ave, Bioengineering Building, Room 306, Charleston, SC 29403, USA.

Cardiac ryanodine receptor (RyR2) is a homotetramer of 560 kDa polypeptides regulated by calmodulin (CaM), which decreases its open probability at diastolic and systolic Ca(2+) concentrations. Point mutations in the CaM-binding domain of RyR2 (W3587A/L3591D/F3603A, RyR2(ADA)) in mice result in severe cardiac hypertrophy, poor left ventricle contraction and death by postnatal day 16, suggesting that CaM inhibition of RyR2 is required for normal cardiac function. Here, we report on Ca(2+) signalling properties of enzymatically isolated, Fluo-4 dialysed whole cell clamped cardiac myocytes from 10-15-day-old wild-type (WT) and homozygous Ryr2(ADA/ADA) mice. Read More

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September 2013

Viral potassium channels as a robust model system for studies of membrane-protein interaction.

Biochim Biophys Acta 2014 Apr 17;1838(4):1096-103. Epub 2013 Jun 17.

Membrane Biophysics, Technical University of Darmstadt, Schnittspahnstrasse 3, 64287 Darmstadt, Germany. Electronic address:

The viral channel KcvNTS belongs to the smallest K(+) channels known so far. A monomer of a functional homotetramer contains only 82 amino acids. As a consequence of the small size the protein is almost fully submerged into the membrane. Read More

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Anion currents in yeast K+ transporters (TRK) characterize a structural homologue of ligand-gated ion channels.

Pflugers Arch 2011 Aug 10;462(2):315-30. Epub 2011 May 10.

Department of Cellular and Molecular Physiology, Yale School of Medicine, 333 Cedar Street, New Haven, CT 06510, USA.

Patch clamp studies of the potassium-transport proteins TRK1,2 in Saccharomyces cerevisiae have revealed large chloride efflux currents: at clamp voltages negative to -100 mV, and intracellular chloride concentrations >10 mM (J. Membr. Biol. Read More

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Mutagenesis and functional analysis of ion channels heterologously expressed in mammalian cells.

J Vis Exp 2010 Oct 1(44). Epub 2010 Oct 1.

Clayton Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies.

We will demonstrate how to study the functional effects of introducing a point mutation in an ion channel. We study G protein-gated inwardly rectifying potassium (referred to as GIRK) channels, which are important for regulating the excitability of neurons. There are four different mammalian GIRK channel subunits (GIRK1-GIRK4)--we focus on GIRK2 because it forms a homotetramer. Read More

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October 2010

Chemical rescue of histidine selectivity filter mutants of the M2 ion channel of influenza A virus.

J Biol Chem 2005 Jun 22;280(22):21463-72. Epub 2005 Mar 22.

Department of Neurobiology and Physiology, Northwestern University, Evanston, Illinois 60208-3500, USA.

The influenza virus M2 proton-selective ion channel activity facilitates virus uncoating, a process that occurs in the acidic environment of the endosome. The M2 channel causes acidification of the interior of the virus particle, which results in viral protein-protein dissociation. The M2 protein is a homotetramer that contains in its aqueous pore a histidine residue (His-37) that acts as a selectivity filter and a tryptophan residue (Trp-41) that acts as a channel gate. Read More

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The gate of the influenza virus M2 proton channel is formed by a single tryptophan residue.

J Biol Chem 2002 Oct 14;277(42):39880-6. Epub 2002 Aug 14.

Department of Neurobiology and Physiology, Northwestern University, Evanston, Illinois 60208-3500, USA.

The influenza virus M2 proton-selective ion channel is known to be essential for acidifying the interior of virions during virus uncoating in the lumen of endosomes. The M2 protein is a homotetramer that contains four 19-residue transmembrane (TM) domains. These TM domains are multifunctional, because they contain the channel pore and also anchor the protein in membranes. Read More

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October 2002

The inositol 1,4,5-trisphosphate receptor.

Ciba Found Symp 1992 ;164:17-29; discussion 29-35

Institute for Protein Research, Osaka University, Japan.

Inositol 1,4,5-trisphosphate (InsP3) is a second messenger that releases Ca2+ from its intracellular stores. The InsP3 receptor has been purified and its cDNA has been cloned. We have found that the InsP3 receptor is identical to P400 protein, first identified as a protein enriched in cerebellar Purkinje cells. Read More

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November 1992
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