{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,17]],"date-time":"2026-02-17T22:29:56Z","timestamp":1771367396610,"version":"3.50.1"},"reference-count":33,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,2,4]],"date-time":"2021-02-04T00:00:00Z","timestamp":1612396800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100008392","name":"Sundhed og Sygdom, Det Frie Forskningsr\u00e5d","doi-asserted-by":"publisher","award":["0602-02404B"],"award-info":[{"award-number":["0602-02404B"]}],"id":[{"id":"10.13039\/100008392","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003554","name":"Lundbeckfonden","doi-asserted-by":"publisher","award":["R54-A5378"],"award-info":[{"award-number":["R54-A5378"]}],"id":[{"id":"10.13039\/501100003554","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100009708","name":"Novo Nordisk Fonden","doi-asserted-by":"publisher","award":["NNF17OC0028584"],"award-info":[{"award-number":["NNF17OC0028584"]}],"id":[{"id":"10.13039\/501100009708","id-type":"DOI","asserted-by":"publisher"}]},{"name":"University Research Foundation","award":["N\/A"],"award-info":[{"award-number":["N\/A"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>(1) Background: The unusual accumulation of Na,K-ATPase complexes in the brush border membrane of choroid plexus epithelial cells have intrigued researchers for decades. However, the full range of the expressed Na,K-ATPase subunits and their relation to the microvillus cytoskeleton remains unknown. (2) Methods: RT-PCR analysis, co-immunoprecipitation, native PAGE, mass spectrometry, and differential centrifugation were combined with high-resolution immunofluorescence histochemistry, proximity ligase assays, and stimulated emission depletion (STED) microscopy on mouse choroid plexus cells or tissues in order to resolve these issues. (3) Results: The choroid plexus epithelium expresses Na,K-ATPase subunits \u03b11, \u03b12, \u03b21, \u03b22, \u03b23, and phospholemman. The \u03b11, \u03b12, \u03b21, and \u03b22, subunits are all localized to the brush border membrane, where they appear to form a complex. The ATPase complexes may stabilize in the brush border membrane via anchoring to microvillar actin indirectly through ankyrin-3 or directly via other co-precipitated proteins. Aquaporin 1 (AQP1) may form part of the proposed multi-protein complexes in contrast to another membrane protein, the Na-K-2Cl cotransporter 1 (NKCC1). NKCC1 expression seems necessary for full brush border membrane accumulation of the Na,K-ATPase in the choroid plexus. (4) Conclusion: A multitude of Na,K-ATPase subunits form molecular complexes in the choroid plexus brush border, which may bind to the cytoskeleton by various alternative actin binding proteins.<\/jats:p>","DOI":"10.3390\/ijms22041569","type":"journal-article","created":{"date-parts":[[2021,2,4]],"date-time":"2021-02-04T12:02:10Z","timestamp":1612440130000},"page":"1569","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Multiple Na,K-ATPase Subunits Colocalize in the Brush Border of Mouse Choroid Plexus Epithelial Cells"],"prefix":"10.3390","volume":"22","author":[{"given":"Inga","family":"Baasch Christensen","sequence":"first","affiliation":[{"name":"Department of Biomedicine, Faculty of Health Science, Aarhus University, 8000 Aarhus, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lei","family":"Cheng","sequence":"additional","affiliation":[{"name":"Department of Biomedicine, Faculty of Health Science, Aarhus University, 8000 Aarhus, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jonathan R.","family":"Brewer","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Molecular Biology, Faculty of Science, University of Southern Denmark, 5230 Odense, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Udo","family":"Bartsch","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Experimental Ophthalmology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1623-199X","authenticated-orcid":false,"given":"Robert A.","family":"Fenton","sequence":"additional","affiliation":[{"name":"Department of Biomedicine, Faculty of Health Science, Aarhus University, 8000 Aarhus, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Helle H.","family":"Damkier","sequence":"additional","affiliation":[{"name":"Department of Biomedicine, Faculty of Health Science, Aarhus University, 8000 Aarhus, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6109-247X","authenticated-orcid":false,"given":"Jeppe","family":"Praetorius","sequence":"additional","affiliation":[{"name":"Department of Biomedicine, Faculty of Health Science, Aarhus University, 8000 Aarhus, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1847","DOI":"10.1152\/physrev.00004.2013","article-title":"Cerebrospinal Fluid Secretion by the Choroid Plexus","volume":"93","author":"Damkier","year":"2013","journal-title":"Physiol. 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