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bioRxiv · 10.1101/2024.05.16.594461

A chromosome-level genome assembly of the cabbage aphid Brevicoryne brassicae

Abstract

The cabbage aphid, Brevicoryne brassicae, is a major pest on Brassicaceae plants, and causes significant yield losses annually. However, lacking genomic resources hinders the progress in understanding this pest at the level of molecular biology. Here, a high-quality, chromosomal-level genome was assembled for B. brassicae based on PacBio HIFI long-read sequencing and Hi-C data. The final assembled size was 429.99 Mb with a scaffold N50 of 93.31 Mb. Importantly, 96.2% of the assembled sequences were anchored to eight chromosomes. The genome recovered 98.50% of BUSCO genes and 92.30% of CEGMA genes, supporting the high level of completeness. By combining high-coverage transcriptome data, a total of 22,671 protein-coding genes and 3,594 lncRNA genes were annotated. Preliminary comparative genomic analyses were focused on genes related to host colonisation, such as chemosensory- and detoxification-related genes, as well as those encoding putative protein effectors and cross-kingdom lncRNA Ya. In summary, our study presents a contiguous and complete genome for B. brassicae that will benefit our understanding of the biology of it and other aphids.

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Wu, J., Li, G., Lin, Z., Zhang, Y., Yu, W., Hu, R., Zhan, S., Chen, Y.. 2024-05-25. A chromosome-level genome assembly of the cabbage aphid Brevicoryne brassicae. https://doi.org/10.1101/2024.05.16.594461

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