{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,4]],"date-time":"2026-03-04T06:15:11Z","timestamp":1772604911962,"version":"3.50.1"},"reference-count":55,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,5,27]],"date-time":"2021-05-27T00:00:00Z","timestamp":1622073600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004281","name":"Narodowe Centrum Nauki","doi-asserted-by":"publisher","award":["2019\/35\/B\/NZ1\/02546"],"award-info":[{"award-number":["2019\/35\/B\/NZ1\/02546"]}],"id":[{"id":"10.13039\/501100004281","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Mitochondria play a key role in energy metabolism within the cell. Potassium channels such as ATP-sensitive, voltage-gated or large-conductance Ca2+-regulated channels have been described in the inner mitochondrial membrane. Several hypotheses have been proposed to describe the important roles of mitochondrial potassium channels in cell survival and death pathways. In the current study, we identified two populations of mitochondrial large-conductance Ca2+-regulated potassium (mitoBKCa) channels in human bronchial epithelial (HBE) cells. The biophysical properties of the channels were characterized using the patch-clamp technique. We observed the activity of the channel with a mean conductance close to 285 pS in symmetric 150\/150 mM KCl solution. Channel activity was increased upon application of the potassium channel opener NS11021 in the micromolar concentration range. The channel activity was completely inhibited by 1 \u00b5M paxilline and 300 nM iberiotoxin, selective inhibitors of the BKCa channels. Based on calcium and iberiotoxin modulation, we suggest that the C-terminus of the protein is localized to the mitochondrial matrix. Additionally, using RT-PCR, we confirmed the presence of \u03b1 pore-forming (Slo1) and auxiliary \u03b23-\u03b24 subunits of BKCa channel in HBE cells. Western blot analysis of cellular fractions confirmed the mitochondrial localization of \u03b1 pore-forming and predominately \u03b23 subunits. Additionally, the regulation of oxygen consumption and membrane potential of human bronchial epithelial mitochondria in the presence of the potassium channel opener NS11021 and inhibitor paxilline were also studied. In summary, for the first time, the electrophysiological and functional properties of the mitoBKCa channel in a bronchial epithelial cell line were described.<\/jats:p>","DOI":"10.3390\/molecules26113233","type":"journal-article","created":{"date-parts":[[2021,5,27]],"date-time":"2021-05-27T23:16:46Z","timestamp":1622157406000},"page":"3233","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Identification of the Large-Conductance Ca2+-Regulated Potassium Channel in Mitochondria of Human Bronchial Epithelial Cells"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2686-5657","authenticated-orcid":false,"given":"Aleksandra","family":"Sek","sequence":"first","affiliation":[{"name":"Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 02-093 Warsaw, Poland"},{"name":"Faculty of Chemistry, University of Warsaw, 02-093 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8913-6881","authenticated-orcid":false,"given":"Rafal P.","family":"Kampa","sequence":"additional","affiliation":[{"name":"Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 02-093 Warsaw, Poland"},{"name":"Department of Physics and Biophysics, Institute of Biology, Warsaw University of Life Sciences\u2014SGGW, 02-776 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4420-9557","authenticated-orcid":false,"given":"Bogusz","family":"Kulawiak","sequence":"additional","affiliation":[{"name":"Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 02-093 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5519-260X","authenticated-orcid":false,"given":"Adam","family":"Szewczyk","sequence":"additional","affiliation":[{"name":"Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 02-093 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7125-0715","authenticated-orcid":false,"given":"Piotr","family":"Bednarczyk","sequence":"additional","affiliation":[{"name":"Department of Physics and Biophysics, Institute of Biology, Warsaw University of Life Sciences\u2014SGGW, 02-776 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"722","DOI":"10.1111\/resp.12542","article-title":"Bronchial epithelial cells: The key effector cells in the pathogenesis of chronic obstructive pulmonary disease?","volume":"20","author":"Gao","year":"2015","journal-title":"Respirology"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Zajac, M., Lewenstam, A., Bednarczyk, P., and Dolowy, K. 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