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bioRxiv · 10.1101/2024.05.29.594498

First chromosome-level genome assembly of the colonial tunicate Botryllus schlosseri

De Thier, O.·Tawfeeq, M. M.·Faure, R.·Lebel, M.·Dru, P.·Blanchoud, S.·Alie, A.·Brown, F. D.·Flot, J.-F.·Tiozzo, S.
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Abstract

Botryllus schlosseri (Tunicata) is a colonial chordate that has long been studied for its multiple developmental pathways and regenerative abilities and its genetically determined allorecognition system based on a polymorphic locus that controls chimerism and cell parasitism. We present the first chromosome-level genome assembly from an isogenic colony of B. schlosseri clade A1 using a mix of long and short reads scaf-folded using Hi-C. This haploid assembly spans 533 Mb, of which 96% are found in 16 chromosome-scale scaffolds. With a BUSCO completeness of 91.2%, this complete and contiguous B. schlosseri genome assembly provides a valuable genomic resource for the scientific community and lays the foundation for future investigations into the molecular mechanisms underlying coloniality, regeneration, histocompatibility, and the immune system in tunicates.

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De Thier, O., Tawfeeq, M. M., Faure, R., Lebel, M., Dru, P., Blanchoud, S., Alie, A., Brown, F. D., Flot, J.-F., Tiozzo, S.. 2024-06-02. First chromosome-level genome assembly of the colonial tunicate Botryllus schlosseri. https://doi.org/10.1101/2024.05.29.594498

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