Chloride ion channels are macromolecular pores providing for passage of chloride ions (and certain other inorganic and organic anions) through the cell membrane, down their electrochemical gradients. Chloride channels are differentially expressed in various cells, to best suit specific cellular activities. They are present in practically all living cells, and regardless of cell specialization t...

The Rockefeller University Press $30.00 J. Gen. Physiol. 2016 Vol. 148 No. 5 367–373 https://doi.org/10.1085/jgp.201611686 367 Elucidating the oligomeric structure of ion channels is central to understanding their function (Marsh and Teichmann, 2015). The vast majority of ion channels are formed by multiple subunits organized as an annulus surrounding a solitary, centrally located ion-conductin...

Chloride (Cl)-conducting channel proteins in plasma and intracellular membranes subserve a diversity of cellular functions, including neurotransmission, osmoregulation, pH regulation in organelles, acid secretion by parietal cells in the stomach, and salt absorption or secretion in exocrine glands (pancreas, sweat gland) and transport epithelia (trachea, intestine). With the notable exception o...

The Rockefeller University Press $30.00 J. Gen. Physiol. 2016 Vol. 148 No. 5 367–373 https://doi.org/10.1085/jgp.201611686 367 Elucidating the oligomeric structure of ion channels is central to understanding their function (Marsh and Teichmann, 2015). The vast majority of ion channels are formed by multiple subunits organized as an annulus surrounding a solitary, centrally located ion-conductin...

The existence of a large conductance voltage sensitive chloride channel is documented in undifferentiated cells (myoblasts) of the L6 rat muscle cell line. At this stage of development the resting membrane conductance is dominated by potassium ions only (Kidokoro 1975). The conductance of the channel in symmetrical 120 mmol/l choline chloride is 331 +/- 4 pS. The probability of the channel bein...

We used DAMI human megakaryocytic leukemia cells to study transmembrane ion currents activated through the G-protein-coupled thrombin receptor pathway. When the cells were stimulated by thrombin receptor-activating peptide, an increase in cytosolic Ca2+ ([Ca2+]i) developed as predicted by the known effect that thrombin exerts in the platelet. We then monitored the membrane potentials of individ...

The Rockefeller University Press $30.00 J. Gen. Physiol. 2016 Vol. 148 No. 5 367–373 https://doi.org/10.1085/jgp.201611686 367 Elucidating the oligomeric structure of ion channels is central to understanding their function (Marsh and Teichmann, 2015). The vast majority of ion channels are formed by multiple subunits organized as an annulus surrounding a solitary, centrally located ion-conductin...

Intrapulmonary chemoreceptors (IPC) are highly responsive respiratory chemoreceptors that innervate the lungs of birds and diapsid reptiles. IPC are stimulated by low levels of lung Pco(2), inhibited by high levels of lung Pco(2), and their vagal afferents serve as a sensory limb for reflex adjustments of breathing depth and rate. Most IPC exhibit both phasic and tonic sensitivity to CO(2), and...

ClC chloride channels are widely expressed in epithelia. Recent insights into the roles of specific ClC channels have emerged from molecular and immunolocalization studies, mouse knockout models, and the linkage of mutations of these channels to the human hereditary diseases Bartter's syndrome and Dent's disease.

Voltage-gated Cl- channels belonging to the ClC family appear to function as homomultimers, but the number of subunits needed to form a functional channel is controversial. To determine subunit stoichiometry, we constructed dimeric human skeletal muscle Cl- channels in which one subunit was tagged by a mutation (D136G) that causes profound changes in voltage-dependent gating. Sucrose-density gr...