Interplay between Cystic Fibrosis Transmembrane Regulator and Gap Junction Channels Made of Connexins 45, 40, 32 and 50 Expressed in Oocytes

Interplay between Cystic Fibrosis Transmembrane Regulator and Gap Junction Channels Made of... The cystic fibrosis transmembrane regulator (CFTR) is a Cl− channel known to influence other channels, including connexin (Cx) channels. To study the functional interaction between CFTR and gap junction channels, we coexpressed in Xenopus oocytes CFTR and either Cx45, Cx40, Cx32 or Cx50 and monitored junctional conductance (G j) and its sensitivity to transjunctional voltage (V j) by the dual voltage-clamp method. Application of forskolin induced a Cl− current; increased G j approximately 750%, 560%, 64% and 8% in Cx45, Cx40, Cx32 and Cx50, respectively; and decreased sensitivity to V j gating, monitored by a change in the ratio between G j steady state and G j peak (G jSS/G jPK) at the pulse. In oocyte pairs expressing just Cx45 in one oocyte (#1) and both Cx45 and CFTR in the other (#2), with negative pulses applied to oocyte #1 forskolin application still increased G j and decreased the sensitivity to V j gating, indicating that CFTR activation is effective even when it affects only one of the two hemichannels and that the G j and V j changes are not artifacts of decreased membrane resistance in the pulsed oocyte. COOH-terminus truncation reduced the forskolin effect on Cx40 (Cx40TR) but not on Cx32 (Cx32TR) channels. The data suggest a cross-talk between CFTR and a variety of gap junction channels. Cytoskeletal scaffolding proteins and/or other intermediate cytoplasmic proteins are likely to play a role in CFTR-Cx interaction. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png The Journal of Membrane Biology Springer Journals

Interplay between Cystic Fibrosis Transmembrane Regulator and Gap Junction Channels Made of Connexins 45, 40, 32 and 50 Expressed in Oocytes

Loading next page...
 
/lp/springer_journal/interplay-between-cystic-fibrosis-transmembrane-regulator-and-gap-7NnvWAed8v
Publisher
Springer-Verlag
Copyright
Copyright © 2007 by Springer Science+Business Media, LLC
Subject
Life Sciences; Biochemistry, general; Human Physiology
ISSN
0022-2631
eISSN
1432-1424
D.O.I.
10.1007/s00232-006-0064-8
Publisher site
See Article on Publisher Site

Abstract

The cystic fibrosis transmembrane regulator (CFTR) is a Cl− channel known to influence other channels, including connexin (Cx) channels. To study the functional interaction between CFTR and gap junction channels, we coexpressed in Xenopus oocytes CFTR and either Cx45, Cx40, Cx32 or Cx50 and monitored junctional conductance (G j) and its sensitivity to transjunctional voltage (V j) by the dual voltage-clamp method. Application of forskolin induced a Cl− current; increased G j approximately 750%, 560%, 64% and 8% in Cx45, Cx40, Cx32 and Cx50, respectively; and decreased sensitivity to V j gating, monitored by a change in the ratio between G j steady state and G j peak (G jSS/G jPK) at the pulse. In oocyte pairs expressing just Cx45 in one oocyte (#1) and both Cx45 and CFTR in the other (#2), with negative pulses applied to oocyte #1 forskolin application still increased G j and decreased the sensitivity to V j gating, indicating that CFTR activation is effective even when it affects only one of the two hemichannels and that the G j and V j changes are not artifacts of decreased membrane resistance in the pulsed oocyte. COOH-terminus truncation reduced the forskolin effect on Cx40 (Cx40TR) but not on Cx32 (Cx32TR) channels. The data suggest a cross-talk between CFTR and a variety of gap junction channels. Cytoskeletal scaffolding proteins and/or other intermediate cytoplasmic proteins are likely to play a role in CFTR-Cx interaction.

Journal

The Journal of Membrane BiologySpringer Journals

Published: Jun 2, 2007

References

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create lists to
organize your research

Export lists, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off