Format

Send to

Choose Destination
Eur Biophys J. 2016 Oct;45(7):599-610. Epub 2016 Jun 7.

Cl- channels in apoptosis.

Author information

1
Institut für Physiologie, Universität Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany.
2
Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
3
Institut für Physiologie, Universität Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany. karl.kunzelmann@ur.de.

Abstract

A remarkable feature of apoptosis is the initial massive cell shrinkage, which requires opening of ion channels to allow release of K+, Cl-, and organic osmolytes to drive osmotic water movement and cell shrinkage. This article focuses on the role of the Cl- channels LRRC8, TMEM16/anoctamin, and cystic fibrosis transmembrane conductance regulator (CFTR) in cellular apoptosis. LRRC8A-E has been identified as a volume-regulated anion channel expressed in many cell types. It was shown to be required for regulatory and apoptotic volume decrease (RVD, AVD) in cultured cell lines. Its presence also determines sensitivity towards cytostatic drugs such as cisplatin. Recent data point to a molecular and functional relationship of LRRC8A and anoctamins (ANOs). ANO6, 9, and 10 (TMEM16F, J, and K) augment apoptotic Cl- currents and AVD, but it remains unclear whether these anoctamins operate as Cl- channels or as regulators of other apoptotic Cl- channels, such as LRRC8. CFTR has been known for its proapoptotic effects for some time, and this effect may be based on glutathione release from the cell and increase in cytosolic reactive oxygen species (ROS). Although we find that CFTR is activated by cell swelling, it is possible that CFTR serves RVD/AVD through accumulation of ROS and activation of independent membrane channels such as ANO6. Thus activation of ANO6 will support cell shrinkage and induce additional apoptotic events, such as membrane phospholipid scrambling.

KEYWORDS:

Anoctamin; Apoptosis; CFTR; Ca2+-activated chloride channels; Cell death; Chloride channel; LRRC8A; RVD; TMEM16A; TMEM16F; TMEM16J; TMEM16K; Volume regulation

PMID:
27270446
DOI:
10.1007/s00249-016-1140-3
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Springer
Loading ...
Support Center