De novo assembly of trachidermus fasciatus genome by nanopore sequencing

Xie, G.; Zhang, X.; Lv, F.; Sang, M.; Hu, H.; Wang, J.; Liu, D.

doi:10.1101/2020.04.18.042093

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bioRxiv · 10.1101/2020.04.18.042093

De novo assembly of trachidermus fasciatus genome by nanopore sequencing

Xie, G.·Zhang, X.·Lv, F.·Sang, M.·Hu, H.·Wang, J.·Liu, D.

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Abstract

Trachidermus fasciatus is a roughskin sculpin fish widely located at the coastal areas of East Asia. Due to the environmental destruction and overfishing, the populations of this species have been under threat. It is important to have a reference genome to study the population genetics, domestic farming, and genetic resource protection. However, currently, there is no reference genome for Trachidermus fasciatus, which has greatly hurdled the studies on this species. In this study, we proposed to integrate nanopore long reads sequencing, Illumina short reads sequencing and Hi-C methods to thoroughly de novo assemble the genome of Trachidermus fasciatus. Our results provided a chromosome-level high quality genome assembly with a total length of about 543 Mb, and with N50 of 23 Mb. Based on de novo gene prediction and RNA sequencing information, a total of 38728 genes were found, including 23191 protein coding genes, 2149 small RNAs, 5572 rRNAs, and 7816 tRNAs. Besides, about 23% of the genome area is covered by the repetitive elements. Furthermore, The BUSCO evaluation of the completeness of the assembled genome is more than 96%, and the single base accuracy is 99.997%. Our study provided the first whole genome reference for the species of Trachidermus fasciatus, which might greatly facilitate the future studies on this species.

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Xie, G., Zhang, X., Lv, F., Sang, M., Hu, H., Wang, J., Liu, D.. 2020-04-18. De novo assembly of trachidermus fasciatus genome by nanopore sequencing. https://doi.org/10.1101/2020.04.18.042093

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