Pseudo-chromosome length genome assembly of a double haploid ‘Bartlett’ pear (Pyrus communis L.)

Linsmith, G.; Rombauts, S.; Montanari, S.; Deng, C. H.; Celton, J.-M.; Guerif, P.; Liu, C.; Lohaus, R.; Zurn, J. D.; Cestaro, A.; Bassil, N. V.; Bakker, L. V.; Schijlen, E.; Gardiner, S. E.; Lespinasse, Y.; Durel, C.-E.; Velasco, R.; Neale, D. B.; Chagne, D.; Van de Peer, Y.; Troggio, M.; Bianco, L.

doi:10.1101/651778

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bioRxiv · 10.1101/651778

Pseudo-chromosome length genome assembly of a double haploid ‘Bartlett’ pear (Pyrus communis L.)

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Abstract

We report an improved assembly and scaffolding of the European pear (Pyrus communis L.) genome (referred to as BartlettDHv2.0), obtained using a combination of Pacific Biosciences RSII Long read sequencing (PacBio), Bionano optical mapping, chromatin interaction capture (Hi-C), and genetic mapping. A total of 496.9 million bases (Mb) corresponding to 97% of the estimated genome size were assembled into 494 scaffolds. Hi-C data and a high-density genetic map allowed us to anchor and orient 87% of the sequence on the 17 chromosomes of the pear genome. About 50% (247 Mb) of the genome consists of repetitive sequences. Comparison with previous assemblies of Pyrus communis. and Pyrus x bretschneideri confirmed the presence of 37,445 protein-coding genes, which is 13% fewer than previously predicted.

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Linsmith, G., Rombauts, S., Montanari, S., Deng, C. H., Celton, J.-M., Guerif, P., Liu, C., Lohaus, R., Zurn, J. D., Cestaro, A., Bassil, N. V., Bakker, L. V., Schijlen, E., Gardiner, S. E., Lespinasse, Y., Durel, C.-E., Velasco, R., Neale, D. B., Chagne, D., Van de Peer, Y., Troggio, M., Bianco, L.. 2019-05-27. Pseudo-chromosome length genome assembly of a double haploid ‘Bartlett’ pear (Pyrus communis L.). https://doi.org/10.1101/651778

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