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Haplotype-resolved chromosomal-level genome assembly of Chrysaora achlyos (black sea nettle)


Abstract

Chrysaora achlyos is a distinctive scyphozoan species characterized by its dark pigmentation and large size. In this study, we generated a haplotype-resolved, chromosome-scale genome assembly for C.achlyos using PacBio HiFi long reads and Hi-C technology. The resulting assembly comprises two haplotypes with sizes of 246.43 Mb (contig N50 = 7.69 Mb) and 248.65 Mb (contig N50 = 7.23 Mb), Additionally, repetitive sequences were characterized, with 110.52 Mb (~44.85%) in haplotype A and 112.57 Mb (~45.27%) in haplotype B. A total of 20,471 and 20,606 protein-coding genes were predicted in haplotypes A and B, respectively. The sequencing depth, mapping coverage, contig continuity, and BUSCO assessment collectively indicated a high-quality haplotype-resolved genome assembly. This high-quality genome assembly provides a foundation for future studies in comparative evolution, toxicology, ecology, and functional genomics.

Data availability

The raw sequencing data from the deep mutational scanning experiments have been deposited in the NCBI Sequence Read Archive (SRA) under BioProject accession number PRJNA1303233 (https://identifiers.org/ncbi/bioproject:PRJNA1303233). The files of genome assembly and gene structure annotation have been deposited at Figshare (https://doi.org/10.6084/m9.figshare.30020194).

Code availability

No specific software or code was developed for this study. The experiments and bioinformatics were performed in accordance with the protocols detailed in the Methods section.

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Acknowledgements

This work was financially supported by the Shanghai Natural Science Foundation General Project (25ZR1401400), and the Military Project (CHJ24C025, CB2023A03).

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Contributions

J.S.Y., J.B.J. and X.Y.G. designed and conceived the study. X.L.Y. and X.Y.G. collected and prepared the samples. Y.J.P., Y.L.F. and J.B.J. performed bioinformatics analysis. Y.Y.L., X.L.Y., B.B.L. and Y.J.P. wrote the manuscript with significant contributions from X.W., Z.F.H., X.H. and S.R.L. J.S.Y. provided the financial support. All authors read and approved the final manuscript.

Corresponding authors

Correspondence to
Jianbo Jian, Xiaoyu Geng or Jishun Yang.

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Li, Y., Yu, X., Li, B. et al. Haplotype-resolved chromosomal-level genome assembly of Chrysaora achlyos (black sea nettle).
Sci Data (2026). https://doi.org/10.1038/s41597-026-07166-7

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  • DOI: https://doi.org/10.1038/s41597-026-07166-7


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