Academic Journal

Identification of the Large-Conductance Ca2+-Regulated Potassium Channel in Mitochondria of Human Bronchial Epithelial Cells

التفاصيل البيبلوغرافية
العنوان: Identification of the Large-Conductance Ca2+-Regulated Potassium Channel in Mitochondria of Human Bronchial Epithelial Cells
المؤلفون: Aleksandra Sek, Rafal P. Kampa, Bogusz Kulawiak, Adam Szewczyk, Piotr Bednarczyk
المصدر: Molecules; Volume 26; Issue 11; Pages: 3233
بيانات النشر: Multidisciplinary Digital Publishing Institute
سنة النشر: 2021
المجموعة: MDPI Open Access Publishing
مصطلحات موضوعية: mitochondria, mitoBK Ca channel, human bronchial epithelial cells, potassium channel modulators, NS11021, paxilline
جغرافية الموضوع: agris
الوصف: 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 µM 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 α pore-forming (Slo1) and auxiliary β3-β4 subunits of BKCa channel in HBE cells. Western blot analysis of cellular fractions confirmed the mitochondrial localization of α pore-forming and predominately β3 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.
نوع الوثيقة: text
وصف الملف: application/pdf
اللغة: English
Relation: Cross-Field Chemistry; https://dx.doi.org/10.3390/molecules26113233
DOI: 10.3390/molecules26113233
الاتاحة: https://doi.org/10.3390/molecules26113233
Rights: https://creativecommons.org/licenses/by/4.0/
رقم الانضمام: edsbas.85F2CC4E
قاعدة البيانات: BASE