Kazuki Ichikawa, Massa J. Shoura, Karen L. Artiles, Dae-Eun Jeong, Chie Owa, Haruka Kobayashi, Yoshihiko Suzuki, Manami Kanamori, Yu Toyoshima, Yuichi Iino, Ann E. Rougvie, Lamia Wahba, Andrew Z. Fire, Erich M. Schwarz, Shinichi Morishita
{"title":"CGC1, a new reference genome for Caenorhabditis elegans","authors":"Kazuki Ichikawa, Massa J. Shoura, Karen L. Artiles, Dae-Eun Jeong, Chie Owa, Haruka Kobayashi, Yoshihiko Suzuki, Manami Kanamori, Yu Toyoshima, Yuichi Iino, Ann E. Rougvie, Lamia Wahba, Andrew Z. Fire, Erich M. Schwarz, Shinichi Morishita","doi":"10.1101/gr.280274.124","DOIUrl":null,"url":null,"abstract":"The original 100.3 Mb reference genome for <em>Caenorhabditis elegans</em>, generated from the wild-type laboratory strain N2, has been crucial for analysis of <em>C. elegans</em> since 1998 and has been considered complete since 2005. Unexpectedly, this long-standing reference was shown to be incomplete in 2019 by a genome assembly from the N2-derived strain VC2010. Moreover, genetically divergent versions of N2 have arisen over decades of research and hindered reproducibility of <em>C. elegans</em> genetics and genomics. Here we provide a 106.4 Mb gap-free, telomere-to-telomere genome assembly of <em>C. elegans</em>, generated from CGC1, an isogenic derivative of the N2 strain. We use improved long-read sequencing and manual assembly of 43 recalcitrant genomic regions to overcome deficiencies of prior N2 and VC2010 assemblies and to assemble tandem repeat loci, including a 772 kb sequence for the 45S rRNA genes. Although many differences from earlier assemblies come from repeat regions, unique additions to the genome are also found. Of 19,972 protein-coding genes in the N2 assembly, 19,790 (99.1%) encode products that are unchanged in the CGC1 assembly. The CGC1 assembly also may encode 183 new protein-coding and 163 new ncRNA genes. CGC1 thus provides both a completely defined reference genome and corresponding isogenic wild-type strain for <em>C. elegans</em>, allowing unique opportunities for model and systems biology.","PeriodicalId":12678,"journal":{"name":"Genome research","volume":"1 1","pages":""},"PeriodicalIF":5.5000,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Genome research","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1101/gr.280274.124","RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"BIOCHEMISTRY & MOLECULAR BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
The original 100.3 Mb reference genome for Caenorhabditis elegans, generated from the wild-type laboratory strain N2, has been crucial for analysis of C. elegans since 1998 and has been considered complete since 2005. Unexpectedly, this long-standing reference was shown to be incomplete in 2019 by a genome assembly from the N2-derived strain VC2010. Moreover, genetically divergent versions of N2 have arisen over decades of research and hindered reproducibility of C. elegans genetics and genomics. Here we provide a 106.4 Mb gap-free, telomere-to-telomere genome assembly of C. elegans, generated from CGC1, an isogenic derivative of the N2 strain. We use improved long-read sequencing and manual assembly of 43 recalcitrant genomic regions to overcome deficiencies of prior N2 and VC2010 assemblies and to assemble tandem repeat loci, including a 772 kb sequence for the 45S rRNA genes. Although many differences from earlier assemblies come from repeat regions, unique additions to the genome are also found. Of 19,972 protein-coding genes in the N2 assembly, 19,790 (99.1%) encode products that are unchanged in the CGC1 assembly. The CGC1 assembly also may encode 183 new protein-coding and 163 new ncRNA genes. CGC1 thus provides both a completely defined reference genome and corresponding isogenic wild-type strain for C. elegans, allowing unique opportunities for model and systems biology.
期刊介绍:
Launched in 1995, Genome Research is an international, continuously published, peer-reviewed journal that focuses on research that provides novel insights into the genome biology of all organisms, including advances in genomic medicine.
Among the topics considered by the journal are genome structure and function, comparative genomics, molecular evolution, genome-scale quantitative and population genetics, proteomics, epigenomics, and systems biology. The journal also features exciting gene discoveries and reports of cutting-edge computational biology and high-throughput methodologies.
New data in these areas are published as research papers, or methods and resource reports that provide novel information on technologies or tools that will be of interest to a broad readership. Complete data sets are presented electronically on the journal''s web site where appropriate. The journal also provides Reviews, Perspectives, and Insight/Outlook articles, which present commentary on the latest advances published both here and elsewhere, placing such progress in its broader biological context.