Related Experiment Video
Updated: Sep 21, 2026

Patch Clamp and Perfusion Techniques for Studying Ion Channels Expressed in Xenopus oocytes
Published on: January 10, 2011
Molecular components of large conductance calcium-activated potassium (BK) channels in mouse pituitary corticotropes
M J Shipston1, R R Duncan, A G Clark
1Department of Biomedical Sciences, University of Edinburgh Medical School, Scotland, UK. mike.shipston@ed.ac.uk
Abstract:
Large-conductance calcium- and voltage- activated potassium (BK) channels play a fundamental role in the signaling pathways regulating mouse anterior pituitary corticotrope function. Here we describe the cloning and functional characterization of the components of mouse corticotrope BK channels. RT-PCR cloning and splice variant analysis of mouse AtT20 D16:16 corticotropes revealed robust expression of mslo transcripts encoding pore-forming alpha-subunits containing the mouse homolog of the 59-amino acid STREX-1 exon at splice site 2. RT-PCR and functional analysis, using the triterpenoid glycoside, DHS-1, revealed that native corticotrope BK channels are not functionally coupled to beta-subunits in vivo. Functional expression of the STREX-1 containing alpha-subunit in HEK 293 cells resulted in BK channels with calcium sensitivity, single-channel conductance, and inhibition by protein kinase A identical to that of native mouse corticotrope BK channels. This report represents the first corticotrope ion channel to be characterized at the molecular level and demonstrates that mouse corticotrope BK channels are composed of alpha-subunits expressing the mouse STREX-1 exon.
More Related Videos
08:46Implementing Patch Clamp and Live Fluorescence Microscopy to Monitor Functional Properties of Freshly Isolated PKD Epithelium
Published on: September 1, 2015
07:14Healthy Brain-pituitary Slices for Electrophysiological Investigations of Pituitary Cells in Teleost Fish
Published on: August 16, 2018
Related Concept Videos
Overview of Secretory Vesicles
Various proteins regulate the aggregation of molecules inside the secretory vesicles. Chromogranins...
Non-gated Ion Channels
Compared to the gated ion channels, the non-gated channels, also known as leakage or passive channels, have no gating mechanism.
The Role of Ion Channels in Neuronal Computation
Sometimes a single EPSP is strong enough to induce an action potential in the postsynaptic neuron. However, multiple presynaptic inputs must often create EPSPs around the same time for the postsynaptic neuron to be sufficiently depolarized to fire an action potential.
Voltage-gated Ion Channels
Generally, all voltage-gated ion channels have a 'voltage-sensing domain' that spans the lipid bilayer. The charged residues in the sensor move in response to the membrane potential changes that open the channel allowing ions movement. There are several types of...
Mechanically-gated Ion Channels
Calmodulin-dependent Signaling
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...