{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T16:13:38Z","timestamp":1789143218113,"version":"build-2803163510"},"reference-count":42,"publisher":"Rockefeller University Press","issue":"7","license":[{"start":{"date-parts":[[2018,6,11]],"date-time":"2018-06-11T00:00:00Z","timestamp":1528675200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/www.rupress.org\/terms\/"},{"start":{"date-parts":[[2018,12,30]],"date-time":"2018-12-30T00:00:00Z","timestamp":1546128000000},"content-version":"vor","delay-in-days":202,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-sa\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["R01-GM-107023"],"award-info":[{"award-number":["R01-GM-107023"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["rupress.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2018,7,2]]},"abstract":"<jats:p>The mitochondrial calcium uniporter is a multisubunit Ca2+ channel that mediates mitochondrial Ca2+ uptake, a cellular process crucial for the regulation of oxidative phosphorylation, intracellular Ca2+ signaling, and apoptosis. In the last few years, genes encoding uniporter proteins have been identified, but a lack of efficient tools for electrophysiological recordings has hindered quantitative analysis required to determine functional mechanisms of this channel complex. Here, we redirected Ca2+-conducting subunits (MCU and EMRE) of the human uniporter to the plasma membrane of Xenopus oocytes. Two-electrode voltage clamp reveals inwardly rectifying Ca2+ currents blocked by a potent inhibitor, Ru360 (half maximal inhibitory concentration, ~4 nM), with a divalent cation conductivity of Ca2+ &amp;gt; Sr2+ &amp;gt; Ba2+, Mn2+, and Mg2+. Patch clamp recordings further reveal macroscopic and single-channel Ca2+ currents sensitive to Ru360. These electrical phenomena were abolished by mutations that perturb MCU-EMRE interactions or disrupt a Ca2+-binding site in the pore. Altogether, this work establishes a robust method that enables deep mechanistic scrutiny of the uniporter using classical strategies in ion channel electrophysiology.<\/jats:p>","DOI":"10.1085\/jgp.201812015","type":"journal-article","created":{"date-parts":[[2018,6,11]],"date-time":"2018-06-11T09:25:12Z","timestamp":1528709112000},"page":"1035-1043","update-policy":"https:\/\/doi.org\/10.1085\/jgp.crossmarkpolicy","source":"Crossref","is-referenced-by-count":19,"title":["Electrical recordings of the mitochondrial calcium uniporter in\n                    <i>Xenopus<\/i>\n                    oocytes"],"prefix":"10.1085","volume":"150","author":[{"given":"Chen-Wei","family":"Tsai","sequence":"first","affiliation":[{"name":"Department of Biochemistry, Brandeis University, Waltham, MA 1"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4277-1885","authenticated-orcid":true,"given":"Ming-Feng","family":"Tsai","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, Brandeis University, Waltham, MA 1"},{"name":"Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO 2"},{"name":"Howard Hughes Medical Institute, Chevy Chase, MD 3"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"291","published-online":{"date-parts":[[2018,6,11]]},"reference":[{"key":"2023072705224111400_bib1","doi-asserted-by":"publisher","first-page":"341","DOI":"10.1038\/nature10234","article-title":"Integrative genomics identifies MCU as an essential component of the mitochondrial calcium uniporter","volume":"476","author":"Baughman","year":"2011","journal-title":"Nature."},{"key":"2023072705224111400_bib2","doi-asserted-by":"publisher","first-page":"1127","DOI":"10.1152\/physrev.1999.79.4.1127","article-title":"Mitochondrial transport of cations: channels, exchangers, and permeability transition","volume":"79","author":"Bernardi","year":"1999","journal-title":"Physiol. 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