BACKGROUND:R2R3-MYB transcription factor (TF) family plays important roles in various biological processes in many plants, especially in the regulation of plant flavonoid accumulation. The fruit of Lonicera caerulea contains abundant anthocyanin. OBJECTIVE:The R2R3-MYB TF family was systematicallyanalyzed according to the RNA-seq data, and the R2R3-MYB candidate genes that were involved in anthocyanin biosynthesis in the fruit of Lonicera caerulea were screened. METHODS:The R2R3-MYB TFs in Lonicera caerulea were identified, and the physical and chemical properties, protein conserved sequence alignment and motifs of each R2R3-MYB TFs were analyzed using bioinformatics methods. The expression levels of these genes and anthocyanin levels in different tissues and different developmental stages of fruit were determined by RT-qPCR and pH shift method. RESULTS:A total of 59 genes encoding R2R3-MYB TFs in Lonicera caerulea were identified and clustered into 20 subgroups (C1 to C20) based on the relationship to AtR2R3-MYBs. Expression profiles showed that the expression of CL6086 and CL552 in fruit were higher than other tissues, and upregulated in the veraison fruit compared to the green ripe fruit. As the expression of the two genes was concurrent with the anthocyanin content, and showed high correlation with anthocyanin biosynthetic structural genes, they were considered as closely related to anthocyanin biosynthesis in the fruit. CONCLUSION:The results provide a systematic analysis of LcR2R3-MYBs, and the foundation for further molecular mechanisms research of anthocyanin biosynthesis regulated by R2R3-MYB in the fruit of Lonicera caerulea.

中文翻译：

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R2R3-MYB基因家族的鉴定揭示了基于RNA-seq数据的蓝花忍冬果实中花青素生物合成的候选基因

背景：R2R3-MYB转录因子（TF）家族在许多植物的各种生物过程中发挥着重要作用，尤其是在植物黄酮积累的调控中。蓝花忍冬的果实含有丰富的花青素。【摘要】：目的:根据RNA-seq数据系统分析R2R3-MYB TF家族,筛选出蓝花忍冬果实中参与花青素生物合成的R2R3-MYB候选基因。方法：鉴定蓝花忍冬中的R2R3-MYB TFs，利用生物信息学方法分析每个R2R3-MYB TFs的理化性质、蛋白质保守序列比对和基序。采用RT-qPCR和pH漂移法测定了这些基因在果实不同组织和不同发育阶段的表达水平和花青素水平。结果：根据与 AtR2R3-MYBs 的关系，共鉴定出 59 个编码蓝花忍冬 R2R3-MYB TFs 的基因，并分为 20 个亚组（C1 至 C20）。表达谱显示CL6086和CL552在果实中的表达高于其他组织，并且与绿色成熟果实相比，在veraison果实中表达上调。由于这两个基因的表达与花色苷含量同时存在，且与花色苷生物合成结构基因的相关性较高，因此被认为与果实中的花色苷生物合成密切相关。结论：本研究结果为LcR2R3-MYBs提供了系统分析，为进一步研究蓝花忍冬果实中R2R3-MYB调控花青素生物合成的分子机制奠定了基础。根据与 AtR2R3-MYB 的关系，共鉴定了 59 个编码蓝花忍冬中 R2R3-MYB TF 的基因，并将其分为 20 个亚组（C1 到 C20）。表达谱显示CL6086和CL552在果实中的表达高于其他组织，并且与绿色成熟果实相比，在veraison果实中表达上调。由于这两个基因的表达与花色苷含量同时存在，且与花色苷生物合成结构基因的相关性较高，因此被认为与果实中的花色苷生物合成密切相关。结论：本研究结果为LcR2R3-MYBs提供了系统分析，为进一步研究蓝花忍冬果实中R2R3-MYB调控花青素生物合成的分子机制奠定了基础。根据与 AtR2R3-MYB 的关系，共鉴定了 59 个编码蓝花忍冬中 R2R3-MYB TF 的基因，并将其分为 20 个亚组（C1 到 C20）。表达谱显示CL6086和CL552在果实中的表达高于其他组织，并且与绿色成熟果实相比，在veraison果实中表达上调。由于这两个基因的表达与花色苷含量同时存在，且与花色苷生物合成结构基因的相关性较高，因此被认为与果实中的花色苷生物合成密切相关。结论：本研究结果为LcR2R3-MYBs提供了系统分析，为进一步研究蓝花忍冬果实中R2R3-MYB调控花青素生物合成的分子机制奠定了基础。