Tasaki Keisuke, Watanabe Aiko, Nemoto Keiichirou, Takahashi Shigekazu, Goto Fumina, Sasaki Nobuhiro, Hikage Takashi, Nishihara Masahiro
Iwate Biotechnology Research Center, Kitakami, Japan.
Hachimantai City Floricultural Research and Development Center, Hachimantai, Japan.
Front Plant Sci. 2022 Jun 22;13:906879. doi: 10.3389/fpls.2022.906879. eCollection 2022.
Gentians cultivated in Japan ( and and hybrids) have blue flowers, but flower colour intensity differs among cultivars. The molecular mechanism underlying the variation in flower colour intensity is unclear. Here, we produced F progeny derived from an F cross of intense- and faint-blue lines and attempted to identify the genes responsible for flower colour intensity using RNA-sequencing analyses. Comparative analysis of flower colour intensity and transcriptome data revealed differentially expressed genes (DEGs), although known flavonoid biosynthesis-related genes showed similar expression patterns. From quantitative RT-PCR (qRT-PCR) analysis, we identified two and four genes with significantly different expression levels in the intense- and faint-blue flower lines, respectively. We conducted further analyses on one of the DEGs, termed , which encodes a putative mini zinc-finger protein homolog, which was most differently expressed in faint-blue individuals. Functional analysis of was performed by producing stable tobacco transformants. -overexpressing tobacco plants showed reduced flower colour intensity compared with untransformed control plants. DNA-marker analysis also confirmed that the allele of the faint-blue flower line correlated well with faint flower colour in F progeny. These results suggest that is one of the key genes involved in determining the flower colour intensity of gentian.
在日本培育的龙胆（及其杂交品种）开蓝色花，但花色深浅在不同品种间存在差异。花色深浅变化的分子机制尚不清楚。在此，我们通过深蓝和浅蓝品系的F杂交产生了F子代，并尝试利用RNA测序分析来鉴定负责花色深浅的基因。尽管已知的类黄酮生物合成相关基因表现出相似的表达模式，但花色深浅与转录组数据的比较分析揭示了差异表达基因（DEGs）。通过定量RT-PCR（qRT-PCR）分析，我们分别在深蓝和浅蓝花朵品系中鉴定出两个和四个表达水平存在显著差异的基因。我们对其中一个名为的DEG进行了进一步分析，它编码一种假定的小锌指蛋白同源物，在浅蓝个体中表达差异最大。通过产生稳定的烟草转化体对进行了功能分析。与未转化的对照植株相比，过表达的烟草植株花色变浅。DNA标记分析也证实，浅蓝花朵品系的等位基因与F子代中的浅花色密切相关。这些结果表明是的关键基因之一，参与决定龙胆的花色深浅。
