TY  - JOUR
TI  - The Welwitschia genome reveals a unique biology underpinning extreme longevity in deserts
AU  - Tao Wan
AU  - Zhiming Liu
AU  - Ilia J. Leitch
AU  - H. P. Xin
AU  - Gillian Maggs‐Kölling
AU  - Yanbing Gong
AU  - Zhen Li
AU  - Eugène Marais
AU  - Yiying Liao
AU  - Can Dai
AU  - Fan Liu
AU  - Qijia Wu
AU  - Chi Song
AU  - Yadong Zhou
AU  - Wei‐Chang Huang
AU  - Kai Jiang
AU  - Qi Wang
AU  - Yong Yang
AU  - Zhixiang Zhong
AU  - Xue Yan
AU  - Guangwan Hu
AU  - Chen Hou
AU  - Yingjuan Su
AU  - Shixiu Feng
AU  - Jijun Yan
AU  - Jinfang Chu
AU  - Fan Chen
AU  - Jinhua Ran
AU  - Xiaoquan Wang
AU  - Yves Van de Peer
AU  - Andrew R. Leitch
AU  - Qingfeng Wang
PY  - 2021
JO  - Nature Communications
DO  - 10.1038/s41467-021-24528-4
UR  - https://doi.org/10.1038/s41467-021-24528-4
AB  - The 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.
ER  -