{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T16:39:28Z","timestamp":1792600768556,"version":"4.5.0"},"reference-count":57,"publisher":"Oxford University Press (OUP)","license":[{"start":{"date-parts":[[2026,10,5]],"date-time":"2026-10-05T00:00:00Z","timestamp":1791158400000},"content-version":"am","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000015","name":"U.S. Department of Energy","doi-asserted-by":"publisher","award":["DE-AC02-05CH11231"],"award-info":[{"award-number":["DE-AC02-05CH11231"]}],"id":[{"id":"10.13039\/100000015","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000015","name":"U.S. Department of Energy","doi-asserted-by":"publisher","award":["ANR-23-CE20-0013"],"award-info":[{"award-number":["ANR-23-CE20-0013"]}],"id":[{"id":"10.13039\/100000015","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100006132","name":"Office of Science","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100006132","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>The spontaneous mutation rate per nucleotide (\u00b5) is a fundamental parameter shaping genome evolution, yet it remains unknown for many eukaryotic groups. Here, we estimated \u00b5 in the freshwater unicellular eukaryote Euglena gracilis, which possesses a 2.4 Gb genome, among the largest reported for unicellular species. We conducted a mutation accumulation experiment using 10 independent MA lines propagated through repeated single-cell bottlenecks and then identified 153 de novo nucleotide mutations. After correction for false negatives, the spontaneous mutation rate was estimated at \u00b5bs=6.60E-10 mutations per nucleotide per generation. E. gracilis exhibits a mutation rate within the range reported for other unicellular eukaryotes and bacteria, supporting the predominant role of effective population size rather than genome size in mutation-rate evolution. Most detected mutations occurred in intergenic regions, and the mutation spectrum was strongly biased toward GC \u2192 AT mutations. These results provide a first estimate of the spontaneous mutation rate in Euglenophyte group and contribute to documenting mutation-rate evolution in large-genome unicellular eukaryotes.<\/jats:p>","DOI":"10.1093\/jeb\/voag096","type":"journal-article","created":{"date-parts":[[2026,10,5]],"date-time":"2026-10-05T15:02:51Z","timestamp":1791212571000},"source":"Crossref","is-referenced-by-count":0,"title":["Spontaneous mutation rate estimation in the large-genome unicellular eukaryote\n                    <i>Euglena gracilis<\/i>"],"prefix":"10.1093","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4591-1524","authenticated-orcid":false,"given":"Marc","family":"Krasovec","sequence":"first","affiliation":[{"name":"Sorbonne Universit\u00e9, CNRS, Laboratoire de Biodiversit\u00e9 et Biotechnologies Microbiennes, LBBM , 66650 Banyuls-sur-Mer ,","place":["France"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna","family":"Lipzen","sequence":"additional","affiliation":[{"name":"DOE Joint Genome Institute, Lawrence Berkeley National Laboratory , Berkeley, CA 94720 ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8999-6785","authenticated-orcid":false,"given":"Kerrie","family":"Barry","sequence":"additional","affiliation":[{"name":"DOE Joint Genome Institute, Lawrence Berkeley National Laboratory , Berkeley, CA 94720 ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Igor V","family":"Grigoriev","sequence":"additional","affiliation":[{"name":"DOE Joint Genome Institute, Lawrence Berkeley National Laboratory , Berkeley, CA 94720 ,","place":["USA"]},{"name":"Department of Plant and Microbial Biology, University of California Berkeley , Berkeley, CA 94720 ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2026,10,5]]},"reference":[{"key":"2026102111473420200_bib1","first-page":"1","article-title":"Evolution of the germline mutation rate across vertebrates","volume-title":"Nature","author":"Bergeron","year":"2023"},{"key":"2026102111473420200_bib2","doi-asserted-by":"publisher","first-page":"R233","DOI":"10.1016\/j.cub.2004.02.054","article-title":"Genome size: does bigger mean worse?","volume":"14","author":"Charlesworth","year":"2004","journal-title":"Current Biology"},{"key":"2026102111473420200_bib3","doi-asserted-by":"publisher","first-page":"780","DOI":"10.1038\/s41597-024-03404-y","article-title":"A chromosome-level genome assembly for the paramylon-producing microalga Euglena gracilis","volume":"11","author":"Chen","year":"2024","journal-title":"Scientific Data"},{"key":"2026102111473420200_bib4","doi-asserted-by":"crossref","unstructured":"Danecek P., Bonfield James K, Liddle J., \u2026 Li H. 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