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bioRxiv · 10.1101/2025.11.10.687602

Chromosome-level genome assemblies of Nicotiana attenuata and Nicotiana obtusifolia

Chakraborty, A.·Xu, S.
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Abstract

Nicotiana attenuata and Nicotiana obtusifolia are two wild tobacco species from the Solanaceae plant family, which are rich in producing diverse specialized metabolites and have been established as ecological model systems for studying plant-insect interactions. The previously published N. attenuata and N. obtusifolia genomes were draft assemblies and had low assembly contiguity, limiting comparative genomic analysis. Here, we performed chromosome-level genome assemblies and annotations of these two species using long-read sequencing and Hi-C data. Both N. attenuata and N. obutosifolia genomes were anchored to 12 chromosomes, with an assembled genome size of 2.19 Gb and 1.3 Gb, respectively. We achieved high BUSCO completeness at the protein level, with 99.3% for N. attenuata and 97.9% for N. obtusifolia. The reference genomes of N. attenuata and N. obtusifolia presented in this study will advance the understanding of metabolic innovations in Solanaceae plants.

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Chakraborty, A., Xu, S.. 2025-11-11. Chromosome-level genome assemblies of Nicotiana attenuata and Nicotiana obtusifolia. https://doi.org/10.1101/2025.11.10.687602

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