Yanzy的个人博客分享 http://blog.sciencenet.cn/u/Yanzy

博文

PNAS∣中国农业大学发文揭示玉米高纬度适应性机理

已有 2664 次阅读 2017-12-28 14:28 |系统分类:论文交流|关键词:学者

2017年12月26日PNAS在线文章,本文为中国农业大学,国家玉米改良中心田丰教授课题组发表,文章揭示了具有转座子活动丰富的玉米基因组,使玉米适应高纬度地区环境的机理


原题目为:

ZmCCT9 enhances maize adaptation to higher latitudes


意义:

开花时间是作物适应当地环境的关键决定因素。作为自然和人工选择的结果,玉米已经进化成为降低了光周期敏感性,适应美洲90°以上纬度地区。在这里,我们展示了一个distant Harbinger-like转座子,作为一个顺式调控元件抑制ZmCCT9表达,以促进在高纬度长日照条件下的开花。ZmCCT9上的转座子和第二个开花时间基因ZmCCT10上的另一功能性转座子,在驯化后依次出现,并被选择为玉米从热带向高纬度传播的靶标。我们的研究结果表明,由转座子插入产生的新的功能变异,帮助玉米迅速在广泛的纬度范围内传播。


Significance:

Flowering time is a critical determinant of crop adaptation to local environments. As a result of natural and artificial selection, maize has evolved a reduced photoperiod sensitivity to adapt to regions over 90° of latitude in the Americas. Here we show that a distant Harbinger-like transposon acts as a cis-regulatory element to repress ZmCCT9 expression to promote flowering under the long days of higher latitudes. The transposon at ZmCCT9 and another functional transposon at a second flowering-time gene, ZmCCT10, arose sequentially following domestication and were targeted by selection as maize spread from the tropics to higher latitudes. Our results demonstrate that new functional variation created by transposon insertions helped maize to spread over a broad range of latitudes rapidly.



摘要:

从墨西哥西南部的热带起源,玉米已遍布在美洲的广阔的纬度。这项壮举,违背了作物禁止在纬度上轻易扩散的规则。玉米如何完成广泛维度的适应,在很大程度上是未知的。通过定位克隆和关联作图,我们将一个开花时间的数量性状基因座定位到CCT转录因子(ZmCCT9)上游57kb处的Harbinger-like转座元件。长日照条件下,Harbinger-like转座元件通过顺式作用来抑制ZmCCT9表达,从而促进开花。通过CRISPR/Cas9敲除ZmCCT9,可在长日照条件下引起早开花。ZmCCT9受昼夜调节,负调控成花素ZCN8的表达,从而导致在长日照条件下的晚花。群体遗传学分析表明,插入在ZmCCT9中的Harbinger-like转座子,以及插入在另一个CCT旁系同源物,ZmCCT10中的CACTA-like转座子,在驯化后依次出现,并被选择为玉米从热带向高纬度传播的靶标。我们的研究结果有助于解释,在前哥伦布时代,具有转座子活动丰富的动态玉米基因组是如何使玉米适应超过90°的纬度地区的。


Abstract:

From its tropical origin in southwestern Mexico, maize spread over a wide latitudinal cline in the Americas. This feat defies the rule that crops are inhibited from spreading easily across latitudes. How the widespread latitudinal adaptation of maize was accomplished is largely unknown. Through positional cloning and association mapping, we resolved a flowering-time quantitative trait locus to a Harbinger-like transposable element positioned 57 kb upstream of a CCT transcription factor (ZmCCT9). The Harbinger-like element acts in cis to repress ZmCCT9 expression to promote flowering under long days. Knockout of ZmCCT9 by CRISPR/Cas9 causes early flowering under long days. ZmCCT9 is diurnally regulated and negatively regulates the expression of the florigen ZCN8, thereby resulting in late flowering under long days. Population genetics analyses revealed that the Harbinger-like transposon insertion at ZmCCT9 and the CACTA-like transposon insertion at another CCT paralog, ZmCCT10, arose sequentially following domestication and were targeted by selection for maize adaptation to higher latitudes. Our findings help explain how the dynamic maize genome with abundant transposon activity enabled maize to adapt over 90° of latitude during the pre-Columbian era.





每日一词


determinant

英[dɪˈtɜ:mɪnənt]

美[dɪˈtɜ:rmɪnənt]

n. 行列式; 决定因素; 决定物; 免疫因子;

adj. 决定因素的; 限定性的;

[例句]The windows and the views beyond them are major determinants of a room's character.

窗户和窗外的景色是决定一个房间特色的主要因素。

[其他] 复数:determinants






https://m.sciencenet.cn/blog-634883-1091887.html

上一篇:New Phytologist∣中国农大发表文揭示黄瓜顶端分生组织维持的...
下一篇:Trends in Plant Science∣PIF3对光和低温信号的整合

0

该博文允许注册用户评论 请点击登录 评论 (0 个评论)

数据加载中...
扫一扫,分享此博文

Archiver|手机版|科学网 ( 京ICP备07017567号-12 )

GMT+8, 2024-3-29 21:40

Powered by ScienceNet.cn

Copyright © 2007- 中国科学报社

返回顶部