Dynamic chromosome rearrangements of the white-spotted bamboo shark shed light on cartilaginous fish diversification mechanisms

Zhang, Y.; Gao, H.; Li, H.; Guo, J.; Wang, M.; Xu, Q.; Wang, J.; Lv, M.; Guo, X.; Liu, Q.; Wei, L.; Ren, H.; Xi, Y.; Guo, Y.; Zhao, Q.; Pan, S.; Liu, C.; Sang, L.; Ding, X.; Wang, C.; Xiang, H.; Song, Y.; Liu, Y.; Liu, S.; Jiang, Y.; Shao, C.; Shi, J.; Sabir, J. S. M.; Sabir, M. J.; Khan, M.; Hajrah, N. H.; Lee, S. M.-Y.; Xu, X.; Yang, H.; Fan, G.; Yang, N.; Liu, X.

doi:10.1101/602136

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bioRxiv · 10.1101/602136

Dynamic chromosome rearrangements of the white-spotted bamboo shark shed light on cartilaginous fish diversification mechanisms

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Abstract

Cartilaginous fishes have a very high phenotypical diversity, a phenomenon for which the mechanisms have been largely unexplored. Here, we report the genome of the white-spotted bamboo shark as the first chromosome-level genome assembly of cartilaginous fish. Using this genome, we illustrated a dynamic chromosome rearrangement process in the bamboo shark, which resulted in the formation of 13 chromosomes, all of which were sparsely distributed with conserved genes and fast-evolving. We found the fast-evolving chromosomes to be enriched in immune-related genes with two chromosomes harboring the major genes for developing the single-chain antibody. We also found chromosome rearrangements to have resulted in the loss of two genes (p2rx3 and p2rx5) which we also showed were involved in cartilage development using a CRISPR/Cas9 approach in zebrafish. Our study highlighted the significance of chromosome rearrangements in the phenotypical evolution of cartilaginous fishes, providing clues to inform further studies on mechanisms for fish diversification.

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Zhang, Y., Gao, H., Li, H., Guo, J., Wang, M., Xu, Q., Wang, J., Lv, M., Guo, X., Liu, Q., Wei, L., Ren, H., Xi, Y., Guo, Y., Zhao, Q., Pan, S., Liu, C., Sang, L., Ding, X., Wang, C., Xiang, H., Song, Y., Liu, Y., Liu, S., Jiang, Y., Shao, C., Shi, J., Sabir, J. S. M., Sabir, M. J., Khan, M., Hajrah, N. H., Lee, S. M.-Y., Xu, X., Yang, H., Fan, G., Yang, N., Liu, X.. 2019-04-08. Dynamic chromosome rearrangements of the white-spotted bamboo shark shed light on cartilaginous fish diversification mechanisms. https://doi.org/10.1101/602136

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