Plant Cell:华中农业大学罗杰研究组发表水稻酚胺类自然变异遗传
2016年8月5日，国际植物科学顶级期刊《The plant Cell》杂志在线发表了华中农业大学生命科学技术学院作物遗传改良国家重点实验室罗杰研究团队题为《Evolutionarily distinct BAHD N-acyltransferases are responsible for natural variation of aromatic amine conjugates in rice》的研究论文。博士研究生彭梦、高彦强和陈伟为该文的共同第一作者，罗杰教授论文为的通讯作者。
据悉，植物的次生代谢产物对植物适应复杂多变的外界环境至关重要。酚胺是一类广泛分布在植物界的次生代谢产物，在植物的生长，发育以及应对各种生物、非生物胁迫反应发挥重要作用。
该项研究利用自然群体和人工群体分析了不同水稻品种中酚胺类物质的含量、分布以及酚胺在水稻不同组织间的差异，进而利用全基因组关联分析(GWAS)和数量性状位点(QTL)，鉴定了8个控制水稻酚胺合成的酰基转移酶基因，包括其中4个编码控制水稻芳香族酚胺的双功能酶。在此基础上，通过同源比对和底物特异性分析，鉴定了决定不同底物特异性的关键氨基酸序列;进而通过进化和生化分析，揭示了控制芳香族酚胺合成的酰基转移酶在单子叶特别是禾本科中特异性的保守进化。本项研究解析了水稻酚胺类自然变异遗传及生化基础，展示了通过多组学结合进行高效基因功能鉴定的新方法，为作物遗传改良实践提供了新资源和新思路。
原文链接：
evolutionarily Distinct BAHD N-Acyltransferases Are Responsible for Natural Variation of Aromatic Amine Conjugates in Rice
原文摘要：
Phenolamides (PAs) are specialized (secondary) metabolites mainly synthesized by BAHD N-acyltransferases. Here, we report metabolic profiling coupled with association and linkage mapping of 11 PAs in rice (Oryza sativa). We identified 22 loci affecting PAs in leaves and 16 loci affecting PAs in seeds. We identified eight BAHD N-acyltransferases located on five chromosomes with diverse specificities, including four aromatic amine N-acyltransferases. We show that genetic variation in PAs is determined, at least in part, by allelic variation in the tissue specificity of expression of the BAHD genes responsible for their biosynthesis. Tryptamine hydroxycinnamoyl transferase 1/2 (Os-THT1/2) and tryptamine benzoyl transferase 1/2 (Os-TBT1/2) were found to be bifunctional tryptamine/tyramineN-acyltransferases. The specificity of Os-THT1 and Os-TBT1 for agmatine involved four tandem arginine residues, which have not been identified as specificity determinants for other plant BAHD transferases, illustrating the versatility of plant BAHD transferases in acquiring new acyl acceptor specificities. With phylogenetic analysis, we identified both divergent and convergent evolution of N-acyltransferases in plants, and we suggest that the BAHD family of tryptamine/tyramine N-acyltransferases evolved conservatively in monocots, especially in Gramineae. Our work demonstrates that omics-assisted gene-to-metabolite analysis provides a useful tool for bulk gene identification and crop genetic improvement.
作者：罗杰
