花色是观赏花卉主要品质性状之一，花青素苷是花色形成的主要色素类群之一，是花色改良的主要调控物质。东方百合花青素苷含量在品种间存在显著差异，是探讨植物花青素苷代谢机制的良好试材。本项目在前期研究基础上，选择东方百合粉色品种‘索邦’和白色品种‘西伯利亚’，研究siRNA介导的花青素苷合成途径的转录后沉默机制。测定各样本色素成分和含量并分析其与花色表型的关系；分离花青素苷合成相关的结构基因和调节基因，分析其在呈色过程中的表达模式，筛选关键的差异表达基因；分析差异基因启动子与转录因子的互作关系；比较前体mRNA和成熟mRNA丰度并进行Northern杂交分析，证明差异基因发生转录后沉默过程；利用小RNA测序，筛选出差异基因的siRNA；利用VIGS系统和稳定的基因干扰株系，验证siRNA的功能。本项目研究对阐明百合花被片花青素苷合成途径的表达调控机制有重要意义，也为百合花色改良的分子育种提供依据。

Flower color is one of the most important quality traits for ornamental plants. Anthocyanins are the most important pigments for flower coloration and the target molecular for color modification in flower breeding. Oriental hybrid lilies with the variety of anthocyanin are good materials to study anthocyanin metabolic mechanism. Base on the strong preliminary work, we are struggling to uncover post-transcriptional gene silencing (PTGS) of anthocyanin synthase pathway caused by endogenous siRNA with white ‘Siberia’ and pink ‘Sorbonne’. Analyze the tepal pigments using HPLC and build the relation between anthocyanin and flower color. Identify the structure gens and regulatory genes in anthocyanin synthase pathway. Determine the expression pattern of those genes in nine developmental stages of tepal with different color using qRT-PCR and find the key candidate genes. Analyze the protein-DNA interaction between transcription factors (MYB and bHLH) and promoters of candidate gens. Compare the expression level of candidate gene pre-mRNA and mature-mRNA to confirm the occurrence of PTGS of candidate genes during the coloration process. Through small-RNA sequencing, screen the siRNAs causing PTGS of candidate genes. And confirm the function of candidate gene siRNAs during the tepal coloration by VIGS and genetic transformation with stable gene interference. This project will uncover a new regulation mechanism on anthocyanin synthase pathway and provide guidance to color modification in molecular breeding of lilies.