Interpretation of the cover story of the Nature sub-issue of True Tie Shu Hua, its complete genome map was released for the first time

Cycads are the oldest surviving seed plants on earth and are known as "living fossil" plants

Cycads have experienced two mass extinctions, several rounds of glacial periods and many other tests.

∆Nature Plants official website screenshot

∆Review the knowledge of plant classification

∆The unveiling ceremony of the 2017 National Gene Bank Shenzhen Xianhu Botanical Garden Living Bank

In this study, some key scientific problems of cycads are selected as the main research directions, and some of them are selected and introduced below

01 Tracing the source and recognizing the ancestors, reconstructing the family tree

Most of the cycads we see now are descendants of several recent radiation evolutions, with a total of 2 families and 10 genera

Furthermore, there has been controversy over whether the common ancestor of gymnosperms underwent a genome-wide doubling event

02 Seeds are poisonous, but they can be beneficial

The research team found a cytotoxic protein gene (fitD) in the genome of Panzhihua cycads, which originated from bacteria and was transferred to fungi and cycads through horizontal gene transfer

Although the toxicity limits the edible function of cycads, it does not prevent it from being useful in human society

03 Gender question, genetic identification

The research team sequenced and analyzed 62 male and female cycads from the Panzhihua Cycad National Reserve, Sichuan, and found a gene with the greatest difference in expression between males and females in the Y chromosome of male plants, which encodes a MADS-box transcription factor , speculated to regulate the sexual organ development of male and female cycads

Cycads also have a special place in terms of sex.

In addition to the above-mentioned agricultural application prospects, cycads have many practical values ​​to be explored.

<p data-track="38" font-size:18px;white-space:normal;background-color:#ffffff;"="" >Liu Yang, Wang Sibo, Li Linzhou, Yang Ting, Wei Tong from Shenzhen BGI Life Sciences Research Institute, Dong Shanshan from Shenzhen Xianhu Botanical Garden, and Wu Shengdan from Lanzhou University are the co-first authors of the paper