{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T16:20:30Z","timestamp":1772814030666,"version":"3.50.1"},"reference-count":42,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2022,6,4]],"date-time":"2022-06-04T00:00:00Z","timestamp":1654300800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)","award":["390686111"],"award-info":[{"award-number":["390686111"]}]},{"name":"Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)","award":["267205415"],"award-info":[{"award-number":["267205415"]}]},{"name":"Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)","award":["2R01GM084211"],"award-info":[{"award-number":["2R01GM084211"]}]},{"DOI":"10.13039\/100000002","name":"the Alexander von Humboldt Professorship (W.B.F.)","doi-asserted-by":"publisher","award":["390686111"],"award-info":[{"award-number":["390686111"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"the Alexander von Humboldt Professorship (W.B.F.)","doi-asserted-by":"publisher","award":["267205415"],"award-info":[{"award-number":["267205415"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"the Alexander von Humboldt Professorship (W.B.F.)","doi-asserted-by":"publisher","award":["2R01GM084211"],"award-info":[{"award-number":["2R01GM084211"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomolecules"],"abstract":"<jats:p>Interactions between physical forces and membrane proteins underpin many forms of environmental sensation and acclimation. Microbes survive osmotic stresses with the help of mechanically gated ion channels and osmolyte transporters. Plant mechanosensitive ion channels have been shown to function in defense signaling. Here, we engineered genetically encoded osmolality sensors (OzTracs) by fusing fluorescent protein spectral variants to the mechanosensitive ion channels MscL from E. coli or MSL10 from A. thaliana. When expressed in yeast cells, the OzTrac sensors reported osmolality changes as a proportional change in the emission ratio of the two fluorescent protein domains. Live-cell imaging revealed an accumulation of fluorescent sensors in internal aggregates, presumably derived from the endomembrane system. Thus, OzTrac sensors serve as osmolality-dependent reporters through an indirect mechanism, such as effects on molecular crowding or fluorophore solvation.<\/jats:p>","DOI":"10.3390\/biom12060787","type":"journal-article","created":{"date-parts":[[2022,6,4]],"date-time":"2022-06-04T09:42:32Z","timestamp":1654335752000},"page":"787","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["OzTracs: Optical Osmolality Reporters Engineered from Mechanosensitive Ion Channels"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2568-7323","authenticated-orcid":false,"given":"Thomas J.","family":"Kleist","sequence":"first","affiliation":[{"name":"Institute for Molecular Physiology, Heinrich Heine University, 40225 D\u00fcsseldorf, Germany"},{"name":"Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305, USA"}]},{"given":"I Winnie","family":"Lin","sequence":"additional","affiliation":[{"name":"Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305, USA"},{"name":"Department of Biology, Stanford University, Stanford, CA 94305, USA"}]},{"given":"Sophia","family":"Xu","sequence":"additional","affiliation":[{"name":"Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305, USA"},{"name":"Department of Biology, Stanford University, Stanford, CA 94305, USA"},{"name":"Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA"}]},{"given":"Grigory","family":"Maksaev","sequence":"additional","affiliation":[{"name":"NSF Center for Engineering Mechanobiology, Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0217-6731","authenticated-orcid":false,"given":"Mayuri","family":"Sadoine","sequence":"additional","affiliation":[{"name":"Institute for Molecular Physiology, Heinrich Heine University, 40225 D\u00fcsseldorf, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4246-065X","authenticated-orcid":false,"given":"Elizabeth S.","family":"Haswell","sequence":"additional","affiliation":[{"name":"NSF Center for Engineering Mechanobiology, Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA"}]},{"given":"Wolf B.","family":"Frommer","sequence":"additional","affiliation":[{"name":"Institute for Molecular Physiology, Heinrich Heine University, 40225 D\u00fcsseldorf, Germany"},{"name":"Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305, USA"},{"name":"Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Nagoya 464-8601, Japan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4332-369X","authenticated-orcid":false,"given":"Michael M.","family":"Wudick","sequence":"additional","affiliation":[{"name":"Institute for Molecular Physiology, Heinrich Heine University, 40225 D\u00fcsseldorf, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2022,6,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"384","DOI":"10.1002\/1439-7633(20020503)3:5<384::AID-CBIC384>3.0.CO;2-H","article-title":"Body shaping under water stress: Osmosensing and osmoregulation of solute transport in bacteria","volume":"3","author":"Morbach","year":"2002","journal-title":"Chembiochem"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"567","DOI":"10.1038\/s41586-020-2933-1","article-title":"Discoveries in structure and physiology of mechanically activated ion channels","volume":"587","author":"Kefauver","year":"2020","journal-title":"Nature"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"207","DOI":"10.1146\/annurev-neuro-070918-050509","article-title":"Mechanosensitive ion channels: Structural features relevant to mechanotransduction mechanisms","volume":"43","author":"Jin","year":"2020","journal-title":"Annu. 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