Xu, F, Wu, X, Jiang, L-H orcid.org/0000-0001-6398-0411 et al. (2 more authors) (2016) An organelle K⁺ channel is required for osmoregulation in Chlamydomonas reinhardtii. Journal of Cell Science, 129 (15). pp. 3008-3014. ISSN 0021-9533
Abstract
Fresh water protozoa and algae face hypotonic challenges in their living environment. Many of them employ a contractile vacuole system to uptake excessive water from the cytoplasm and expel it to the environment to achieve cellular homeostasis. K+, a major osmolyte in contractile vacuole, is predicted to create higher osmolarity for water influx. Molecular mechanisms for K+ permeation through the plasma membrane have been well studied. However, how K+ permeates organelles such as the contractile vacuole is not clear. Here, we show that the six-transmembrane K+ channel KCN11 in Chlamydomonas is exclusively localized to contractile vacuole. Ectopic expression of KCN11 in HEK293T cells results in voltage-gated K+ channel activity. Disruption of the gene or mutation of key residues for K+ permeability of the channel leads to dysfunction of cell osmoregulation in very hypotonic conditions. The contractile cycle is inhibited in the mutant cells with a slower rate of contractile vacuole swelling, leading to cell death. These data demonstrate a new role for six-transmembrane K+ channels in contractile vacuole functioning and provide further insights into osmoregulation mediated by the contractile vacuole.
Metadata
Item Type: | Article |
---|---|
Authors/Creators: |
|
Copyright, Publisher and Additional Information: | © 2016. Published by The Company of Biologists Ltd This is an author produced version of a paper published in Journal of Cell Science. Uploaded in accordance with the publisher's self-archiving policy. |
Keywords: | Chlamydomonas, Contractile vacuole, Osmoregulation, K+ channel, KCN11 |
Dates: |
|
Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Biological Sciences (Leeds) > School of Biomedical Sciences (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 11 Jul 2016 09:12 |
Last Modified: | 19 Jul 2017 05:31 |
Published Version: | http://dx.doi.org/10.1242/jcs.188441 |
Status: | Published |
Publisher: | Company of Biologists |
Identification Number: | 10.1242/jcs.188441 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:102016 |