{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,5]],"date-time":"2026-10-05T03:51:58Z","timestamp":1791172318832,"version":"4.1.0"},"reference-count":42,"publisher":"Oxford University Press (OUP)","issue":"9","license":[{"start":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T00:00:00Z","timestamp":1787788800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100008982","name":"National Science Foundation","doi-asserted-by":"publisher","award":["OCE-1656070"],"award-info":[{"award-number":["OCE-1656070"]}],"id":[{"id":"10.13039\/501100008982","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000936","name":"Gordon and Betty Moore Foundation","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100000936","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,8,29]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Warnowiid dinoflagellates are known for possessing two of the most complex structures known in single cells: multiprojectile nematocysts and the camera eye-like ocelloid. The rarity of warnowiids and their intractability in culture have stymied efforts to understand the function and role of these structures. Recent single-cell transcriptome sequencing efforts revealed that the plastid within the ocelloid complex (analogous to the retina in an animal eye) may have lost photosystem II (PSII), while retaining photosystem I as a putative light-sensing mechanism. However, this finding was produced from only 18 cells across five genera and did not include many of the known lineages within this group. To interrogate this finding, we generated single-cell transcriptomes for 12 additional species, including from two previously unsampled genera, collected from subarctic and tropical environments. A search for photosynthesis-related genes across all taxa supports previous findings that PSII has likely been lost in the warnowiid ocelloid plastid. Additionally, our updated phylogenomic analysis reveals that warnowiids can be divided into two major subclades based on the possession of nematocysts: armed and unarmed. Moreover, ocelloid size, shape, position, and gene expression are distinct between armed and unarmed warnowiids and between genera in some cases, indicating that ocelloid function may differ between lineages and this may be linked to differences in energy and nutritional strategy.<\/jats:p>","DOI":"10.1093\/pnasnexus\/pgag287","type":"journal-article","created":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T07:40:01Z","timestamp":1787816401000},"source":"Crossref","is-referenced-by-count":0,"title":["Evolution of complex organelles in ocelloid-bearing dinoflagellates"],"prefix":"10.1093","volume":"5","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7435-7609","authenticated-orcid":false,"given":"Elizabeth C","family":"Cooney","sequence":"first","affiliation":[{"name":"Department of Botany, University of British Columbia , Vancouver, BC , V6T 1Z4","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4222-6086","authenticated-orcid":false,"given":"Corey C","family":"Holt","sequence":"additional","affiliation":[{"name":"Department of Botany, University of British Columbia , Vancouver, BC , V6T 1Z4","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3986-3068","authenticated-orcid":false,"given":"Gordon","family":"Lax","sequence":"additional","affiliation":[{"name":"Department of Botany, University of British Columbia , Vancouver, BC , V6T 1Z4","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Patrick J","family":"Keeling","sequence":"additional","affiliation":[{"name":"Department of Botany, University of British Columbia , Vancouver, BC , V6T 1Z4","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2026,8,27]]},"reference":[{"key":"2026100423165820400_pgag287-B1","doi-asserted-by":"crossref","DOI":"10.5962\/bhl.title.24995","volume-title":"The free-living unarmored Dinoflagellata","author":"Kofoid","year":"1921"},{"key":"2026100423165820400_pgag287-B2","first-page":"127","article-title":"Evolution structurale et ultrastructurale de l\u2019ocelloide d\u2019Erythropsidinium pavillardi Kofoid et Swezy (Peridinien Warnowiidae Lindemann) au cours des divisions binaire et palintomiques","volume":"13","author":"Greuet","year":"1977","journal-title":"Protistologica"},{"key":"2026100423165820400_pgag287-B3","doi-asserted-by":"crossref","first-page":"204","DOI":"10.1038\/nature14593","article-title":"Eye-like ocelloids are built from different endosymbiotically acquired components","volume":"523","author":"Gavelis","year":"2015","journal-title":"Nature"},{"key":"2026100423165820400_pgag287-B4","doi-asserted-by":"crossref","first-page":"440","DOI":"10.1111\/j.1550-7408.2009.00420.x","article-title":"Molecular phylogeny of the ocelloid-bearing dinoflagellates Erythropsidinium and Warnowia (Warnowiaceae, Dinophyceae)","volume":"56","author":"G\u00f3mez","year":"2009","journal-title":"J Eukaryot Microbiol"},{"key":"2026100423165820400_pgag287-B5","doi-asserted-by":"crossref","first-page":"116","DOI":"10.1186\/1471-2148-9-116","article-title":"Molecular phylogeny of ocelloid-bearing dinoflagellates (Warnowiaceae) as inferred from SSU and LSU rDNA sequences","volume":"9","author":"Hoppenrath","year":"2009","journal-title":"BMC Evol Biol"},{"key":"2026100423165820400_pgag287-B6","doi-asserted-by":"crossref","first-page":"4252","DOI":"10.1016\/j.cub.2023.08.052","article-title":"Photosystems in the eye-like organelles of heterotrophic warnowiid dinoflagellates","volume":"33","author":"Cooney","year":"2023","journal-title":"Curr Biol"},{"key":"2026100423165820400_pgag287-B7","doi-asserted-by":"crossref","first-page":"wrae188","DOI":"10.1093\/ismejo\/wrae188","article-title":"Hidden syndinian and perkinsid infections in dinoflagellate hosts revealed by single-cell transcriptomics","volume":"18","author":"Cooney","year":"2024","journal-title":"ISME J"},{"key":"2026100423165820400_pgag287-B8","doi-asserted-by":"crossref","first-page":"177","DOI":"10.1242\/jcs.s2-69.274.177","article-title":"On Proterythropsis vigilans, n.sp","volume":"S2\u201369","author":"Marshall","year":"1925","journal-title":"J Cell Sci"},{"key":"2026100423165820400_pgag287-B9","first-page":"461","article-title":"Les crit\u00e8res de d\u00e9termination chez les p\u00e9ridiniens Warnowiidae Lindemann","volume":"8","author":"Greuet","year":"1972","journal-title":"Protistologica"},{"key":"2026100423165820400_pgag287-B10","first-page":"1","volume-title":"Ergebnisse Der Plankton-Expedition Der Humboldt-Stiftung","author":"Sch\u00fctt","year":"1895"},{"key":"2026100423165820400_pgag287-B11","first-page":"3","volume-title":"Die Nat\u00fcrlichen Pflanzenfamilien. 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