biostudies-literatureDe Thier OINSB-DBM and Sorbonne University AAP Emergence 2021 FAPESPANRFonds de la Recherche Scientifique (F.R.S.-FNRS) via PDRgiaf097https://www.ebi.ac.uk/biostudies/studies/S-EPMC12448946biostudies-literatureUnknown14<h4>Background</h4>Botryllus schlosseri (Tunicata) is a colonial, laboratory model tunicate recognized for its remarkable developmental diversity, its regenerative abilities, and its peculiar genetically determined allorecognition system governed by a polymorphic locus controlling chimerism and cell parasitism.<h4>Results</h4>We report the first chromosome-level genome assembly of B. schlosseri subclade A1. By integrating long and short reads with Hi-C scaffolding, we produced both a phased diploid genome assembly and a conventional collapsed consensus sequence of 533 Mb. Of this total length, 96% belonged to 16 chromosome-scale scaffolds, with a BUSCO completeness score of 91.4%. We then compared our assembly with other high-quality tunicate genomes, revealing some synteny conservation buGigaScienceFirst chromosome-level genome assembly of the colonial chordate model Botryllus schlosseri (Tunicata).PMC1244894619/06927-5ANR-24-CE02-2277ANR-14-CE02-0019-01T.0078.23 to J.F.F.15/50164-5De Thier OTawfeeq MMFlot JFBlanchoud STiozzo SDru PBrown FDAlie ALebel MFaure RfalseFirst chromosome-level genome assembly of the colonial chordate model Botryllus schlosseri (Tunicata).<h4>Background</h4>Botryllus schlosseri (Tunicata) is a colonial, laboratory model tunicate recognized for its remarkable developmental diversity, its regenerative abilities, and its peculiar genetically determined allorecognition system governed by a polymorphic locus controlling chimerism and cell parasitism.<h4>Results</h4>We report the first chromosome-level genome assembly of B. schlosseri subclade A1. By integrating long and short reads with Hi-C scaffolding, we produced both a phased diploid genome assembly and a conventional collapsed consensus sequence of 533 Mb. Of this total length, 96% belonged to 16 chromosome-scale scaffolds, with a BUSCO completeness score of 91.4%. We then compared our assembly with other high-quality tunicate genomes, revealing some synteny conservation bu2025-01-01T00:00:00Z2025 Jan2026-06-03T23:22:49.11Z2026-05-03T03:11:17.256ZS-EPMC124489464097159410.1093/gigascience/giaf097