RumiR858a靶向R2R3-MYB123调控黑莓果实花色苷积累的作用机制

黑莓为蔷薇科悬钩子属重要经济林果，因其成熟果实富含花色苷而具较强的抗氧化特性，揭示花色苷合成和积累的调控规律对提高黑莓抗氧化能力有重要意义。已有研究多集中于黑莓不同品种花色苷等活性物质含量分析及花色苷合成通路中酶基因的鉴定，而对关键miRNAs或转录因子的调控机制研究尚未开展。前期通过代谢组和转录组联合分析黑莓果实花色苷合成和代谢的变化规律，结合小RNA、降解组测序和表达分析，初步推论RumiR858a靶向R2R3-MYB123在调控黑莓果实花色苷积累中起关键作用。本研究拟克隆鉴定RumiR858a和R2R3-MYB123，并探究RumiR858a和R2R3-MYB123的互作关系，继而通过遗传转化黑莓验证其功能。探索“miR858→R2R3-MYB→花色苷合成”模式作用于黑莓成熟果实花色苷积累的调控机理，深度剖析花色苷合成和代谢调控机制，为黑莓品种改良与抗氧化成分利用提供详尽的基础依据。

Blackberry is an important economic shrub species of Rubus in Rosaceae family, whose mature fruit is rich in anthocyanins and has strong antioxidant properties. It is of great significance to reveal the regulatory mechanisms of anthocyanin biosynthesis and accumulation for improving the antioxidant capacity of blackberry. Previous studies always focused on the analysis of anthocyanins and other active substances contents in different blackberry varieties and the identification of enzyme genes in the anthocyanin biosynthesis pathway, but the regulatory mechanism of key miRNAs or transcription factors has not been carried out. In the early stage, integrative of transcriptome and metabolome was applied to analysis changes of anthocyanin synthesis and metabolism during ripening and color changing of blackberry fruit. Combined with small RNA, degradome sequencing and expression analysis, we preliminarily concluded that RumiR858a targeting R2R3-MYB123 played a key role in regulating anthocyanin accumulation in blackberry fruit. This study intends to clone and identify RumiR858a and R2R3-MYB123 of blackberry, explore the interaction between RumiR858a and R2R3-MYB123, and then verify their functions through genetic transformation of blackberry. Objective to explore the regulation mechanism of "miR858 → R2R3-MYB transcription factor → anthocyanin synthesis and accumulation" mode on anthocyanin accumulation in mature blackberry fruit, and to deeply analyze the regulation mechanism of anthocyanin synthesis and metabolism, so as to provide a detailed basis for the improvement of blackberry varieties and the utilization of antioxidants.