Center for Plant Science Innovation, University of Nebraska, Lincoln, NE 68588, USA.
Guangdong Key Laboratory of Ornamental Plant Germplasm Innovation and Utilization, Environmental Horticulture Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China.
Genes (Basel). 2019 Jul 25;10(8):559. doi: 10.3390/genes10080559.
Solanaceae have played an important role in elucidating how flower color is specified by the flavonoid biosynthesis pathway (FBP), which produces anthocyanins and other secondary metabolites. With well-established reverse genetics tools and rich genomic resources, Solanaceae provide a robust framework to examine the diversification of this well-studied pathway over short evolutionary timescales and to evaluate the predictability of genetic perturbation on pathway flux. Genomes of eight Solanaceae species, nine related asterids, and four rosids were mined to evaluate variation in copy number of the suite of FBP enzymes involved in anthocyanin biosynthesis. Comparison of annotation sources indicated that the NCBI annotation pipeline generated more and longer FBP annotations on average than genome-specific annotation pipelines. The pattern of diversification of each enzyme among asterids was assessed by phylogenetic analysis, showing that the CHS superfamily encompasses a large paralogous family of ancient and recent duplicates, whereas other FBP enzymes have diversified via recent duplications in particular lineages. Heterologous expression of a pansy F3'5'H gene in tobacco changed flower color from pink to dark purple, demonstrating that anthocyanin production can be predictably modified using reverse genetics. These results suggest that the Solanaceae FBP could be an ideal system to model genotype-to-phenotype interactions for secondary metabolism.
茄科在阐明类黄酮生物合成途径（FBP）如何指定花色方面发挥了重要作用，该途径产生花青素和其他次生代谢物。茄科植物具有成熟的反向遗传学工具和丰富的基因组资源，为在短进化时间内研究这条研究充分的途径的多样化，并评估遗传干扰对途径通量的可预测性提供了一个强大的框架。挖掘了 8 种茄科植物、9 种相关的菊类植物和 4 种蔷薇类植物的基因组，以评估参与花青素生物合成的整套 FBP 酶的拷贝数变异。对注释来源的比较表明，NCBI 注释流水线平均比基因组特异性注释流水线生成更多和更长的 FBP 注释。通过对菊类植物中每种酶的系统发育分析评估了其多样化模式，表明 CHS 超家族包含一个庞大的、古老和近期复制的同源家族，而其他 FBP 酶则通过特定谱系中的近期复制而多样化。在烟草中异源表达一种三色堇 F3'5'H 基因使花色从粉红色变为深紫色，表明可以使用反向遗传学可预测地修饰花青素的产生。这些结果表明，茄科植物 FBP 可以成为用于模拟次生代谢物的基因型-表型相互作用的理想系统。
