{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T08:03:07Z","timestamp":1790841787504,"version":"4.1.0"},"reference-count":37,"publisher":"The Company of Biologists","issue":"10","license":[{"start":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T00:00:00Z","timestamp":1790812800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"name":"Anshun Branch of Guizhou Tobacco Company","award":["2023ASXM04"],"award-info":[{"award-number":["2023ASXM04"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,10,15]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:p>Conventional strategies for obtaining planarian tissue for genomic DNA extraction rely on diet-based rearing or amputation-induced regeneration. These approaches are inapplicable to soil-dwelling flatworms that predominantly reproduce by egg-laying and lack regenerative capacity, such as the recently discovered nematode predator Luticola nematophagus. Here, we developed a protocol for the sequential isolation, purification, and collection of L.\u00a0nematophagus eggs, comprising three steps: (1) physical sieving through sintered meshes of graded pore sizes under recirculating water flow to exclude nontarget eggs; (2) chemical digestion with 8% (w\/w, weight\/weight) urea or 5% (w\/w) hydroxylamine hydrochloride under continuous aeration for 18\u2005h to eliminate contaminating microinvertebrates; and (3) manual sorting under a stereomicroscope. Genomic DNA extracted from purified eggs exhibited A260\/A280 ratios of 1.93\u20132.00 and A260\/A230 ratios exceeding 2.0, meeting the quality thresholds for whole-genome sequencing. Successful PCR amplification of 18S and 28S ribosomal DNA (rDNA) fragments confirmed the suitability of the DNA for downstream molecular analyses. Compared with untreated controls, urea treatment (8% urea and manual sorting) reduced the final hatching rate by 5.2% and delayed the half-hatching time by 5.1\u2005days, whereas hydroxylamine hydrochloride treatment (5% hydroxylamine hydrochloride and manual sorting) reduced the final hatching rate by 11.6% and delayed the half-hatching time by 7.9\u2005days. However, the majority of the eggs remained viable. The quality of the extracted DNA was further confirmed by successful whole-genome sequencing, which yielded a chromosome-level genome assembly, indicating its suitability for the most demanding downstream applications.<\/jats:p>","DOI":"10.1242\/bio.062663","type":"journal-article","created":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T07:46:46Z","timestamp":1790840806000},"source":"Crossref","is-referenced-by-count":0,"title":["A protocol for sequential isolation, purification, and collection of\n                    <i>Luticola nematophagus<\/i>\n                    eggs to obtain high-quality genomic DNA"],"prefix":"10.1242","volume":"15","author":[{"given":"Shouhui","family":"Pan","sequence":"first","affiliation":[{"name":"Anshun Branch of Guizhou Tobacco Company 1 , Anshun 561000, Guizhou ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-7759-0453","authenticated-orcid":false,"given":"Chongtao","family":"Guo","sequence":"additional","affiliation":[{"name":"Biotechnology Institute of Guizhou Province 2 , Guiyang 550006, Guizhou ,","place":["China"]},{"name":"Guizhou Key Laboratory of Agricultural Biotechnology 3 , Guiyang 550006, Guizhou ,","place":["China"]},{"name":"Ministry of Agriculture and Rural Affairs Key Laboratory of Crop Genetic Resources and Germplasm Innovation in Karst Region 4 , Guiyang 550006, Guizhou ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hai","family":"Zhang","sequence":"additional","affiliation":[{"name":"Anshun Branch of Guizhou Tobacco Company 1 , Anshun 561000, Guizhou ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hao","family":"Cen","sequence":"additional","affiliation":[{"name":"Anshun Branch of Guizhou Tobacco Company 1 , Anshun 561000, Guizhou ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Quan","family":"Zhang","sequence":"additional","affiliation":[{"name":"Anshun Branch of Guizhou Tobacco Company 1 , Anshun 561000, Guizhou ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fei","family":"Dai","sequence":"additional","affiliation":[{"name":"Anshun Branch of Guizhou Tobacco Company 1 , Anshun 561000, Guizhou ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Congyong","family":"Li","sequence":"additional","affiliation":[{"name":"Anshun Branch of Guizhou Tobacco Company 1 , Anshun 561000, Guizhou ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qing","family":"Yang","sequence":"additional","affiliation":[{"name":"Anshun Branch of Guizhou Tobacco Company 1 , Anshun 561000, Guizhou ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhouqiong","family":"Zhang","sequence":"additional","affiliation":[{"name":"Biotechnology Institute of Guizhou Province 2 , Guiyang 550006, Guizhou ,","place":["China"]},{"name":"Guizhou Key Laboratory of Agricultural Biotechnology 3 , Guiyang 550006, Guizhou ,","place":["China"]},{"name":"Ministry of Agriculture and Rural Affairs Key Laboratory of Crop Genetic Resources and Germplasm Innovation in Karst Region 4 , Guiyang 550006, Guizhou ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wang","family":"Yin","sequence":"additional","affiliation":[{"name":"Biotechnology Institute of Guizhou Province 2 , Guiyang 550006, Guizhou ,","place":["China"]},{"name":"Guizhou Key Laboratory of Agricultural Biotechnology 3 , Guiyang 550006, Guizhou ,","place":["China"]},{"name":"Ministry of Agriculture and Rural Affairs Key Laboratory of Crop Genetic Resources and Germplasm Innovation in Karst Region 4 , Guiyang 550006, Guizhou ,","place":["China"]},{"name":"Guizhou Zhikang Biotechnology Company 5 , Anshun 561000 ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Renju","family":"Deng","sequence":"additional","affiliation":[{"name":"Biotechnology Institute of Guizhou Province 2 , Guiyang 550006, Guizhou ,","place":["China"]},{"name":"Guizhou Key Laboratory of Agricultural Biotechnology 3 , Guiyang 550006, Guizhou ,","place":["China"]},{"name":"Ministry of Agriculture and Rural Affairs Key Laboratory of Crop Genetic Resources and Germplasm Innovation in Karst Region 4 , Guiyang 550006, Guizhou ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"237","published-online":{"date-parts":[[2026,10,1]]},"reference":[{"key":"2026100103464194100_BIO062663C1","doi-asserted-by":"publisher","first-page":"4692","DOI":"10.1093\/nar\/25.22.4692","article-title":"Universal and rapid salt-extraction of high quality genomic DNA for PCR-based techniques","volume":"25","author":"Aljanabi","year":"1997","journal-title":"Nucleic Acids Res."},{"key":"2026100103464194100_BIO062663C2","doi-asserted-by":"publisher","first-page":"131","DOI":"10.1016\/0044-8486(94)90420-0","article-title":"Mitochondrial DNA variation and markers of species identity in two penaeid shrimp species: Penaeus monodon Fabricius and P","volume":"127","author":"Bouchon","year":"1994","journal-title":"Aquaculture"},{"key":"2026100103464194100_BIO062663C3","doi-asserted-by":"publisher","first-page":"764","DOI":"10.2136\/SSSAJ1972.03615995003600050024X","article-title":"Selective dissolution of manganese oxides from soils and sediments with acidified hydroxylamine hydrochloride","volume":"36","author":"Chao","year":"1972","journal-title":"Soil Sci. 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Zool."},{"key":"2026100103464194100_BIO062663C5","doi-asserted-by":"publisher","first-page":"1","DOI":"10.3897\/zoologia.34.e12622","article-title":"Observations on food preference of Neotropical land planarians (Platyhelminthes), with emphasis on Obama anthropophila, and their phylogenetic diversification","volume":"34","author":"Cseh","year":"2017","journal-title":"Zoologia."},{"key":"2026100103464194100_BIO062663C6","doi-asserted-by":"publisher","first-page":"1","DOI":"10.3897\/zookeys.894.35281","article-title":"First report and molecular characterization of the dagger nematode","volume":"894","author":"Daramola","year":"2019","journal-title":"ZooKeys"},{"key":"2026100103464194100_BIO062663C7","doi-asserted-by":"publisher","first-page":"611","DOI":"10.1111\/j.1471-8286.2005.01009.x","article-title":"Nematode\u2013specific PCR primers for the 18S small subunit rRNA gene","volume":"5","author":"Floyd","year":"2005","journal-title":"Mol. Ecol. 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Sci."}],"container-title":["Biology Open"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.biologists.com\/bio\/article-pdf\/doi\/10.1242\/bio.062663\/3719947\/bio062663.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/journals.biologists.com\/bio\/article-pdf\/doi\/10.1242\/bio.062663\/3719947\/bio062663.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T07:46:46Z","timestamp":1790840806000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.biologists.com\/bio\/article\/15\/10\/bio062663\/373064\/A-protocol-for-sequential-isolation-purification"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,10,1]]},"references-count":37,"journal-issue":{"issue":"10","published-print":{"date-parts":[[2026,10,15]]}},"URL":"https:\/\/doi.org\/10.1242\/bio.062663","relation":{},"ISSN":["2046-6390"],"issn-type":[{"value":"2046-6390","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,10,1]]},"article-number":"bio062663"}}