Chrysanthemum [Dendranthema morifolium Tzvel.] is an ornamental plant grown under long-term artificial cultivation conditions. In production, early Chrysanthemum blossoms are often promoted by artificial short-day treatment. However, we found that the flower colour of Chrysanthemum blossoms induced by artificial short-day treatment was lighter than those induced by the natural photoperiod. To explore the intrinsic mechanism of colour fading in flowers, we performed full-length transcriptome sequencing of Chrysanthemum morifolium cv. 'Jinbeidahong' using single-molecule real-time sequencing and RNA-sequencing under natural daylight (ND) and short daylight (SD) conditions. The clustered transcriptome sequences were assigned to various databases, such as NCBI, Swiss-Prot, Gene Ontology and so on. The comparative results of digital gene expression analysis revealed that there were differentially expressed transcripts (DETs) in the four stages under ND and SD conditions. In addition, the expression patterns of anthocyanin biosynthesis structural genes were verified by quantitative real-time PCR. The major regulators of the light signalling ELONGATED HYPOCOTYL5 genes were markedly upregulated under ND conditions. The patterns of anthocyanin accumulation were consistent with the expression patterns of CHI1 and 3GT1. The results showed that the anthocyanin synthesis is tightly regulated by the photoperiod, which will be useful for molecular breeding of Chrysanthemum.

中文翻译：

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短期光周期下菊花花色变化的分子机制的转录组分析。

菊花（Dendranthema morifolium Tzvel。）是在长期人工栽培条件下生长的观赏植物。在生产中，通常通过人工短日处理来促进菊花的早期开花。然而，我们发现人工短日处理诱导的菊花花色比自然光周期诱导的花色浅。为了探究花朵褪色的内在机理，我们对菊花cv进行了全长转录组测序。在自然日光（ND）和短日光（SD）条件下使用单分子实时测序和RNA测序的“金杯大红”。将簇状转录组序列分配给各种数据库，例如NCBI，Swiss-Prot，Gene Ontology等。数字基因表达分析的比较结果表明，在ND和SD条件下，四个阶段都有差异表达的转录本（DET）。另外，通过实时定量PCR验证了花色苷生物合成结构基因的表达模式。在ND条件下，光信号化ELONGATED HYPOCOTYL5基因的主要调节子显着上调。花青素积累的模式与CHI1和3GT1的表达模式一致。结果表明，花青素的合成受到光周期的严格调控，这将有助于菊花的分子育种。通过实时定量PCR验证了花色苷生物合成结构基因的表达模式。在ND条件下，光信号化ELONGATED HYPOCOTYL5基因的主要调节子显着上调。花青素积累的模式与CHI1和3GT1的表达模式一致。结果表明，花青素的合成受到光周期的严格调控，这将有助于菊花的分子育种。通过实时定量PCR验证了花色苷生物合成结构基因的表达模式。在ND条件下，光信号化ELONGATED HYPOCOTYL5基因的主要调节子显着上调。花青素积累的模式与CHI1和3GT1的表达模式一致。结果表明，花青素的合成受到光周期的严格调控，这将有助于菊花的分子育种。