Wan, TaoLiu, ZhimingLeitch, Ilia J.Xin, HaipingMaggs-Kolling, GillianGong, YanbingLi, ZhenMarais, EugeneLiao, YiyingDai, CanLiu, FanWu, QijiaSong, ChiZhou, YadongHuang, WeichangJiang, KaiWang, QiYang, YongZhong, ZhixiangYang, MingYan, XueHu, GuangwanHou, ChenSu, YingjuanFeng, ShixiuYang, JiYan, JijunChu, JinfangChen, FanRan, JinhuaWang, XiaoquanVan de Peer, YvesLeitch, Andrew R.Wang, Qingfeng2022-02-042022-02-042021Wan, T., Liu, Z., Leitch, I.J. et al. The Welwitschia genome reveals a unique biology underpinning extreme longevity in deserts. Nature Communications 12, 4247 (2021). https://doi.org/10.1038/s41467-021-24528-4.2041-1723 (online)10.1038/s41467-021-24528-4http://hdl.handle.net/2263/83636The gymnosperm Welwitschia mirabilis belongs to the ancient, enigmatic gnetophyte lineage. It is a unique desert plant with extreme longevity and two ever-elongating leaves. We present a chromosome-level assembly of its genome (6.8 Gb/1 C) together with methylome and transcriptome data to explore its astonishing biology. We also present a refined, high-quality assembly of Gnetum montanum to enhance our understanding of gnetophyte genome evolution. The Welwitschia genome has been shaped by a lineage-specific ancient, whole genome duplication (~86 million years ago) and more recently (1-2 million years) by bursts of retrotransposon activity. High levels of cytosine methylation (particularly at CHH motifs) are associated with retrotransposons, whilst long-term deamination has resulted in an exceptionally GC-poor genome. Changes in copy number and/or expression of gene families and transcription factors (e.g. R2R3MYB, SAUR) controlling cell growth, differentiation and metabolism underpin the plant’s longevity and tolerance to temperature, nutrient and water stress.en© The Author(s) 2021. This article is licensed under a Creative Commons Attribution 4.0 International License.Welwitschia genomeLongevityDesertsArticle