{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T14:53:31Z","timestamp":1791384811891,"version":"4.3.3"},"reference-count":41,"publisher":"Oxford University Press (OUP)","issue":"10","license":[{"start":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T00:00:00Z","timestamp":1790208000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003977","name":"Israel Science Foundation","doi-asserted-by":"publisher","award":["652\/20"],"award-info":[{"award-number":["652\/20"]}],"id":[{"id":"10.13039\/501100003977","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003977","name":"Israel Science Foundation","doi-asserted-by":"publisher","award":["711\/25"],"award-info":[{"award-number":["711\/25"]}],"id":[{"id":"10.13039\/501100003977","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,10,3]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Spliceosomal introns are nearly ubiquitous across eukaryotes, yet the constraints shaping their length remain poorly understood. Generally, introns shorter than \u223c30\u2005bp are considered absent from animals. Here, we show that such ultra-short introns evolved independently at least twice within Metazoa. Using long-read sequencing, we assembled and annotated the genome of the myxobolid myxozoan Henneguya salminicola and identified exceptionally short introns with a median length of 27\u2005bp. Comparative analyses of 51 metazoan genomes revealed that extreme intron shortening characterizes myxobolids, with Thelohanellus kitauei and Myxobolus rasmusseni exhibiting the shortest median intron length (22\u2005bp) among sequenced animals. Outside Myxozoa, similarly short introns were found only in the dicyemid Dicyema japonicum. Sequence-logo analyses showed reduced 5\u2032 and 3\u2032 splice-site motifs in myxobolids and D. japonicum relative to other animals. Together, these results demonstrate that introns shorter than 30\u2005bp occur in animals, and that extreme intron shortening evolved convergently in at least two parasitic animal lineages.<\/jats:p>","DOI":"10.1093\/molbev\/msag244","type":"journal-article","created":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T11:50:03Z","timestamp":1790164203000},"source":"Crossref","is-referenced-by-count":0,"title":["The shortest animal introns: insights from parasitic cnidarians"],"prefix":"10.1093","volume":"43","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3572-0142","authenticated-orcid":false,"given":"Racheli","family":"Hadjez","sequence":"first","affiliation":[{"name":"School of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University , Tel Aviv 6997801 ,","place":["Israel"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9463-2575","authenticated-orcid":false,"given":"Tal","family":"Pupko","sequence":"additional","affiliation":[{"name":"The Shmunis School of Biomedicine and Cancer Research, George S. Wise Faculty of Life Sciences, Tel Aviv University , Tel Aviv 6997801 ,","place":["Israel"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7180-6672","authenticated-orcid":false,"given":"Stephen D","family":"Atkinson","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Oregon State University , Corvallis, OR 97331 ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5047-244X","authenticated-orcid":false,"given":"Doroth\u00e9e","family":"Huchon","sequence":"additional","affiliation":[{"name":"School of Zoology, George S. 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