{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,7]],"date-time":"2026-09-07T10:07:34Z","timestamp":1788775654557,"version":"build-2803163510"},"reference-count":53,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,7]],"date-time":"2026-09-07T00:00:00Z","timestamp":1788739200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Plant Sci."],"abstract":"<jats:p>\n                    Plant cation\/H+ exchanger 1 (CAX1) is a vacuolar Ca\n                    <jats:sup>2+<\/jats:sup>\n                    \/H\n                    <jats:sup>+<\/jats:sup>\n                    antiporter that plays a central role in calcium homeostasis. The initial 36 residues of CAX1 make up the amino-terminal regulatory region (NRR), this defining feature mediates autoinhibition and serves as a target for phosphorylation and protein-protein interactions. While CAX1 has been viewed as a transporter, recent genetic studies suggest a broader functional role. Loss of CAX1 enhances tolerance to anoxia and submergence stress, while synthetic biology reveals that transport-deficient amino-terminal modules of CAX1 influence stress responses. Notably, a dominant-negative amino-terminal construct phenocopies\n                    <jats:italic>cax1<\/jats:italic>\n                    loss-of-function mutants, whereas a transport-deficient amino-terminal module lacking the autoinhibitory region restores anoxia sensitivity in a\n                    <jats:italic>cax1<\/jats:italic>\n                    background. These observations are difficult to explain through altered calcium transport alone. In this review, we summarize current understanding of CAX1 structure, regulation, and physiological function and evaluate evidence supporting transport-independent activities of the amino terminus. We propose that the amino-terminal architecture of CAX1 could function as a control module that integrates environmental and cellular cues to influence stress responses. This framework expands the functional scope of CAX1 beyond ion exchange and might suggest that membrane transport proteins contribute directly to signaling networks.\n                  <\/jats:p>","DOI":"10.3389\/fpls.2026.1937940","type":"journal-article","created":{"date-parts":[[2026,9,7]],"date-time":"2026-09-07T09:08:55Z","timestamp":1788772135000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["CAX1 beyond calcium transport: evidence for a transport-independent regulatory module in plants"],"prefix":"10.3389","volume":"17","author":[{"given":"Fernando","family":"Chavira","sequence":"first","affiliation":[{"name":"Department of Chemistry and Biochemistry, University of Texas at El Paso","place":["El Paso, TX, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniella","family":"Chacon-Avila","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biochemistry, University of Texas at El Paso","place":["El Paso, TX, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shayan","family":"Sarkar","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, University of Texas at El Paso","place":["El Paso, TX, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kendal D.","family":"Hirschi","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, University of Texas at El Paso","place":["El Paso, TX, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ricardo Andres","family":"Bernal","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biochemistry, University of Texas at El Paso","place":["El Paso, TX, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,7]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1093\/plphys\/kiae641","article-title":"CAX-INTERACTING PROTEIN4 depletion causes early lethality and pre-mRNA missplicing in Arabidopsis","volume":"197","author":"Aceituno-Valenzuela","year":"2024","journal-title":"Plant Physiol."},{"key":"B2","doi-asserted-by":"publisher","first-page":"3991","DOI":"10.1007\/s00018-020-03518-7","article-title":"Genome-wide analysis of CCHC-type zinc finger (ZCCHC) proteins in yeast, Arabidopsis, and humans","volume":"77","author":"Aceituno-Valenzuela","year":"2020","journal-title":"Cell. 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