RT Journal Article
SR Electronic
T1 Genome of octoploid plant maca (<em>Lepidium meyenii</em>) illuminates genomic basis for high altitude adaptation in the central Andes
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 017590
DO 10.1101/017590
A1 Jing Zhang
A1 Yang Tian
A1 Liang Yan
A1 Guanghui Zhang
A1 Xiao Wang
A1 Yan Zeng
A1 Jiajin Zhang
A1 Xiao Ma
A1 Yuntao Tan
A1 Ni Long
A1 Yangzi Wang
A1 Yujin Ma
A1 Yu Xue
A1 Shumei Hao
A1 Shengchao Yang
A1 Wen Wang
A1 Liangsheng Zhang
A1 Yang Dong
A1 Wei Chen
A1 Jun Sheng
YR 2015
UL http://biorxiv.org/content/early/2015/04/06/017590.abstract
AB Maca (Lepidium meyenii Walp, 2n = 8× = 64) of Brassicaceae family is an Andean economic plant cultivated on the 4000-4500 meters central sierra in Peru. Considering the rapid uplift of central Andes occurred 5 to 10 million years ago (Mya), an evolutionary question arises on how plants like maca acquire high altitude adaptation within short geological period. Here, we report the high-quality genome assembly of maca, in which two close-spaced maca-specific whole genome duplications (WGDs, ∼ 6.7 Mya) were identified. Comparative genomics between maca and close-related Brassicaceae species revealed expansions of maca genes and gene families involved in abiotic stress response, hormone signaling pathway and secondary metabolite biosynthesis via WGDs. Retention and subsequent evolution of many duplicated genes may account for the morphological and physiological changes (i.e. small leaf shape and loss of vernalization) in maca for high altitude environment. Additionally, some duplicated maca genes under positive selection were identified with functions in morphological adaptation (i.e. MYB59) and development (i.e. GDPD5 and HDA9). Collectively, the octoploid maca genome sheds light on the important roles of WGDs in plant high altitude adaptation in the Andes.