Functional characterization of the NCC27 nuclear protein in stable transfected CHO‐K1 cells

  title={Functional characterization of the NCC27 nuclear protein in stable transfected CHO‐K1 cells},
  author={Raffaella Tonini and Arnaldo Ferroni and Stella M. Valenzuela and Kristina Warton and Terence J. Campbell and Samuel N. Breit and Michele Mazzanti},
  journal={The FASEB Journal},
  pages={1171 - 1178}
NCC27 belongs to a family of small, highly conserved, organellar ion channel proteins. It is constitutively expressed by native CHO‐K1 and dominantly localized to the nucleus and nuclear membrane. When CHO‐K1 cells are transfected with NCC27‐expressing constructs, synthesized proteins spill over into the cytoplasm and ion channel activity can then be detected on the plasma as well as nuclear membrane. This provided a unique opportunity to directly compare electrophysiological characteristics of… 

The nuclear chloride ion channel NCC27 is involved in regulation of the cell cycle

It is demonstrated that Cl− ion channel blockers known to block NCC27 led to arrest of CHO‐K1 cells in the G2/M stage of the cell cycle, the same stage at which this ion channel is selectively expressed on the plasma membrane.

Point Mutations in the Transmembrane Region of the Clic1 Ion Channel Selectively Modify Its Biophysical Properties

Results show that mutation of the two charged amino acids (K37 and R29) in the putative transmembrane region of CLIC1 alters the biophysical properties of the ion channel in both artificial bilayers and cells, which strongly suggests that, despite its unusual structure,CLIC1 itself is able to form a chloride ion channel.

Recombinant CLIC1 (NCC27) Assembles in Lipid Bilayers via a pH-dependent Two-state Process to Form Chloride Ion Channels with Identical Characteristics to Those Observed in Chinese Hamster Ovary Cells Expressing CLIC1*

This work indicates that the CLIC1 ion channel is likely to consist of a tetrameric assembly of subunits and indicates that despite its size and unusual properties, it is able to form a completely functional ion channel in the absence of any other ancillary proteins.

A Plant Homolog of Animal Chloride Intracellular Channels (CLICs) Generates an Ion Conductance in Heterologous Systems*

Analysis of the subcellular localization of AtDHRA1::GFP showed that the bulk of the protein was located as soluble form in the cytoplasm; however, an appreciable fraction of it could also be found in association with the non-soluble microsomal fraction, suggesting that plant members of the GST superfamily have similar to those from animals multiple functions.

Redox regulation of CLIC1 by cysteine residues associated with the putative channel pore.

The findings support a simple structural hypothesis to explain how CLIC1 oligomers form pores in membranes, and suggest that native channels may be regulated by a novel mechanism involving the formation and reduction of intersubunit disulphide bonds.

Spatiotemporal regulation of chloride intracellular channel protein CLIC4 by RhoA.

It is shown that cytosolic CLIC4 undergoes rapid but transient translocation to discrete domains at the plasma membrane upon stimulation of G(13)-coupled, RhoA-activating receptors, such as those for lysophosphatidic acid, thrombin, and sphingosine-1-phosphate.

Tissue and subcellular distribution of CLIC1

The cell and tissue specific patterns of CLIC1 expression suggest it may play distinct roles in different cell types, particularly in certain polarized columnar epithelia, and may play a role in apical membrane recycling.



NCC27, a homolog of intracellular Cl- channel p64, is expressed in brush border of renal proximal tubule.

In human and mouse kidney, NCC27 is expressed at low levels in most cells of the kidney, and is highly expressed in glomeruli, in periarterial smooth muscle, and in the apical membrane of a subset of cortical tubule cells.

Molecular cloning and characterization of p64, a chloride channel protein from kidney microsomes.

Molecular Cloning and Expression of a Chloride Ion Channel of Cell Nuclei*

The molecular cloning and characterization of a nuclear ion channel protein, designated nuclear chloride channel-27 (NCC27), from the human myelomonocytic cell line, U937, is described, which represents the first human member of a new class of organellar chloride ion channel proteins.

Molecular Cloning and Characterization of a Mitogen-activated Protein Kinase-associated Intracellular Chloride Channel*

The observed interaction between CLIC3 and ERK7 is the first demonstration of a stable complex between a protein that activates chloride ion transport and a member of the mitogen-activated protein kinase family of signal transducers.

Ion channels in the nuclear envelope

The patch-clamp technique is applied to isolated murine pronuclei and shows that the nuclear envelope contains K+-selective channels which have multiple conductance states, the maximal conductance being 200 pS, which may be important in balancing the charge carried by the movement of macromolecules in and out of the nucleus.

Gating mechanism of the nuclear pore complex channel in isolated neonatal and adult mouse liver nuclei

By using actin filament disrupter, the number of active channels in adult isolated nuclei is increased and it is suggested that a functional interaction between actin filaments and the nuclear pore complex could regulate nucleocytoplasmic permeability.

Volume-activated Cl- channels.

The intracellular potassium and chloride channels: properties, pharmacology and function (review).

This mini-review describes the basic properties, pharmacology, and current hypotheses concerning the functional role of intracellular potassium and chloride channels.