Natural variations of BrHISN2 provide a genetic basis for growth-flavour trade-off in different Brassica rapa subspecies
Natural variations of BrHISN2 provide a genetic basis for growth-flavour trade-off in different Brassica rapa subspecies
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BrHISN2 的自然变异为不同甘蓝亚种的生长风味权衡提供了遗传基础
DOI：
10.1111/nph.17515
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发表时间：
2021
期刊：
影响因子：
9.4
通讯作者：
Zhang Fenglan
中科院分区：
文献类型：
--
作者：
Su Tongbing;Wang Weihong;Li Peirong;Xin Xiaoyun;Yu Yangjun;Zhao Xiuyun;Zhang Deshuang;Yu Shuancang;Zhang Fenglan
在油菜育种过程中对产量的选择可能会对其他性状产生意想不到的影响，如风味。LYH-型（浅黄色头）大白菜（白菜）和五彩（白菜）。由于其独特的风味和黄色的叶子，这些品种越来越受欢迎。然而，这些性状相互作用的分子机制仍然未知。我们对LYH和五彩（包括转基因植物）的叶片黄化进行了精细定位和全基因组探索分析，以确定致病基因。我们确定了BrHISN 2，一种组氨酸生物合成的限速酶，通过破坏LYH叶绿体导致叶片黄化。正常生长的Brhisn 2突变体植物在子叶-幼苗阶段变得黄化和衰老。启动子中的序列变异赋予BrHISN 2冷依赖性表达，可能导致LYH和五彩的叶片黄化。两个DREcis元件的插入和随后由DREs向启动子募集两个CBF 2蛋白提供了BrHISN 2在植物中的冷诱导表达可塑性。LYH和五彩都是在秋季种植的，此时温度逐渐降低，因此CBF 2-BrHISN 2模块可能最大化了基因-环境相互作用对育种的益处。我们确定了这些白菜型油菜中叶绿素合成和生长-风味权衡的机制联系。
Selection for yield duringB.rapabreeding may have unintended consequences for other traits, such as flavour. LYH‐type (light yellow head) Chinese cabbage (Brassicarapassp.pekinensis) and wucai (BrassicarapaL. ssp.chinensisvar.rosularis) varieties are becoming popular because of their unique flavour and yellow leaves. However, the molecular mechanism underlying the interplay for these traits remains unknown.We conducted a fine mapping and genome‐wide exploration analysis of the leaf yellowing of LYH and wucai, including transgenic plants, to identify causal genes.We identified that BrHISN2, a rate‐limiting enzyme in histidine biosynthesis, causes leaf yellowing by destroying LYH chloroplasts. Normal growingBrhisn2mutant plants became etiolated and senesced at the cotyledon‐seedling stage. Sequence variations in the promoter confers cold‐dependent expression onBrHISN2, probably resulting in leaf yellowing in LYH and wucai. Insertions of two DREciselements and the subsequent recruitment of two CBF2 proteins by the DREs to the promoter provided the cold‐induced expression plasticity ofBrHISN2in plants. Both LYH and wucai are farmed in the fall, in which the temperature gradually decreases, therefore the CBF2‐BrHISN2module probably maximises the benefits of gene–environment interaction for breeding.We determined the mechanistic connections of chlorophyll synthesis and the growth‐flavour trade‐off in theseB.rapavarieties.