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bioRxiv · 10.1101/2021.04.08.438412

Chromosome-level genome assembly of Acanthopagrus latus using PacBio and Hi-C technologies

Abstract

The yellowfin seabream, Acanthopagrus latus, is widely distributed throughout the Indo-West Pacific. This fish is an ideal model species in which to study the mechanism of sex reversal since it exhibits a specific feature: sequential hermaphrodite. Here, we report a chromosome-scale assembly of the A. latus based on PacBio and Hi-C data. 22,485 protein-coding genes were annotated in whole genome level using transcriptome data. Taken together, this highly accurate, chromosome-level reference genome can provide a valuable resource to elucidate the mechanism of sex reversal for A. latus. Background & SummaryEvolution of sex, especially the evolution of different sexual systems, is a fascinating subject in evolutionary biology. The Sparidae, commonly known as seabreams or progies, is a family of fishes of the order Perciformes. And this family consist about 150 species in the world, which are mainly coastal fish1. Previous researchers mentioned that Sparidae is an ideal taxon to study the evolution history and adaptive significance of sexual systems, particularly for both types of sequential hermaphroditism, given that this group contains many protogyny, protandry and genochorist species2. The yellowfin seabream, Acanthopagrus latus is a protandry species which belongs to the Sparidae family. It is widely distributed in Indo-West Pacific area3. It has a great relevance for marine aquaculture and its biology is well focused on reproductive physiology and nutrition4. Interestingly, A. latus has a special gender feature is that it belongs to protandrous sexual system (initially as male and change later to female)5. Most of the past studies of A. latus mainly focused on the reproductive biology, population structure, aquaculture and taxonomy3,4,6-8. Although some sex reversal related genes were found in A. latus, the lack of genomic resources still limit us to elucidate the mechanism of sex reversal for this species.9,10. In addition, this lack was also limited the studies of evolution of sexual systems for Sparidae. In this study, long-read (PacBio SMRT) sequencing and Hi-C sequencing technologies were applied to construct a high quality reference genome for yellowfin seabream. This high-quality genome can provide a valuable resource to elucidate the mechanism of sex reversal for A. latus. Furthermore, this genome can also facilitate the studies of evolution of sexual systems for Sparidae.

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Gao, D., Fang, W., Collins, J., Torrance, J., Yan, Y., Lin, G., Xie, J., Howe, K., Lu, J.. 2021-04-10. Chromosome-level genome assembly of Acanthopagrus latus using PacBio and Hi-C technologies. https://doi.org/10.1101/2021.04.08.438412

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