{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,28]],"date-time":"2025-10-28T00:04:56Z","timestamp":1761609896690,"version":"3.32.0"},"reference-count":48,"publisher":"Oxford University Press (OUP)","issue":"6","license":[{"start":{"date-parts":[[2013,2,19]],"date-time":"2013-02-19T00:00:00Z","timestamp":1361232000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"},{"start":{"date-parts":[[2013,4,22]],"date-time":"2013-04-22T00:00:00Z","timestamp":1366588800000},"content-version":"vor","delay-in-days":62,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"funder":[{"name":"National Aeronautics and Space Administration graduate student research fellowship"}],"content-domain":{"domain":["setac.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2013,6,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:sec>\n                  <jats:title>\u2003<\/jats:title>\n                  <jats:p>Paralytic shellfish toxins are secondary metabolites produced by several species of dinoflagellates and cyanobacteria. Known targets of these toxins, which typically occur at detrimental concentrations during harmful algal blooms, include voltage-gated ion channels in humans and other mammals. However, the effects of the toxins on the co-occurring phytoplankton community remain unknown. The present study examined the molecular mechanisms of the model photosynthetic alga Chlamydomonas reinhardtii in response to saxitoxin exposure as a means of gaining insight into the phytoplankton community response to a bloom. Previous work with yeast indicated that saxitoxin inhibited copper uptake, so experiments were designed to examine whether saxitoxin exhibited a similar mode of action in algae. Expression profiling following exposure to saxitoxin or a copper chelator produced similar profiles in copper homeostasis genes, notably induction of the cytochrome c6 (CYC6) and copper transporter (COPT1, CTR1) genes. Cytochrome c6 is used as an alternative to plastocyanin under conditions of copper deficiency, and immunofluorescence data showed this protein to be present in a significantly greater proportion of saxitoxin-exposed cells compared to controls. Live-cell imaging with a copper-sensor probe for intracellular labile Cu(I) confirmed that saxitoxin blocked copper uptake. Extrapolations of these data to phytoplankton metabolic processes along with the copper transporter as a molecular target of saxitoxin based on existing structural models are discussed. Environ Toxicol Chem 2013;32:1388\u20131395. \u00a9 2013 SETAC<\/jats:p>\n               <\/jats:sec>","DOI":"10.1002\/etc.2187","type":"journal-article","created":{"date-parts":[[2013,2,19]],"date-time":"2013-02-19T22:11:52Z","timestamp":1361311912000},"page":"1388-1395","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Paralytic shellfish toxins inhibit copper uptake in <i>Chlamydomonas reinhardtii<\/i>"],"prefix":"10.1093","volume":"32","author":[{"given":"Kathleen D.","family":"Cusick","sequence":"first","affiliation":[{"name":"Center for Environmental BiotechnologyThe University of Tennessee, , Knoxville, Tennessee , USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Randall K.","family":"Wetzel","sequence":"additional","affiliation":[{"name":"Cell Signaling Technology, , Danvers, Massachusetts , USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"suffix":"Jr.","given":"Steven C.","family":"Minkin","sequence":"additional","affiliation":[{"name":"Center for Environmental BiotechnologyThe University of Tennessee, , Knoxville, Tennessee , USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sheel C.","family":"Dodani","sequence":"additional","affiliation":[{"name":"Department of ChemistryUniversity of California, , Berkeley, California , USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Steven W.","family":"Wilhelm","sequence":"additional","affiliation":[{"name":"Department of MicrobiologyThe University of Tennessee, , Knoxville, Tennessee , USA"},{"name":"Center for Environmental BiotechnologyThe University of Tennessee, , Knoxville, Tennessee , USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gary S.","family":"Sayler","sequence":"additional","affiliation":[{"name":"UT-ORNL Joint Institute of Biological SciencesOak Ridge National Lab, , Oak Ridge, Tennessee , USA"},{"name":"Department of Ecology and Evolutionary BiologyThe University of Tennessee, , Knoxville, Tennessee , USA"},{"name":"Department of MicrobiologyThe University of Tennessee, , Knoxville, Tennessee , USA"},{"name":"Center for Environmental BiotechnologyThe University of Tennessee, , Knoxville, Tennessee , USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"286","published-online":{"date-parts":[[2013,2,19]]},"reference":[{"key":"2025010314242740100_etc2187-bib-0001","first-page":"329","volume-title":"Toxic Dinoflagellates","author":"Catterall","year":"1985"},{"key":"2025010314242740100_etc2187-bib-0002","doi-asserted-by":"crossref","first-page":"349","DOI":"10.3390\/md6020349","article-title":"Neurotoxins from marine dinoflagallates: A brief review","volume":"6","author":"Wang","year":"2008","journal-title":"Mar Drugs"},{"key":"2025010314242740100_etc2187-bib-0003","doi-asserted-by":"crossref","first-page":"2185","DOI":"10.3390\/md8072185","article-title":"Neurotoxic alkaloids: Saxitoxin and its 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