VuMYB1基因启动子变异导致笃斯越桔果实花青苷积累功能缺失的分子调控机制

白果笃斯是笃斯越桔果实花青苷合成障碍突变体，其果实在低温刺激下也不能合成花青苷，是研究花青苷合成和调控机理的良好材料。项目组前期筛选的VuMYB1，是调控花青苷合成和白果笃斯越桔果皮着色变异的关键基因，其作用机制以及调控白果变异机理尚不清楚。本研究拟以笃斯越桔及白果变种为试材，比较其启动子序列与结构，利用酵母单杂交筛选其上游转录因子，研究启动子功能及其变异，阐明白果笃斯越桔果实花青苷合成障碍的分子机制，开发分子标记并用于自然群体鉴定；研究VuMYB1及其上游转录因子在不同光温组合处理下的表达模式；研究瞬时和过量表达对拟南芥、果实愈伤组织及白果变种果实花青苷合成的影响，VIGS验证基因沉默对野生型果实花青苷合成的影响；酵母双杂交筛选其互作蛋白，探讨VuMYB1互作蛋白复合体对花青苷合成结构基因的调控作用。研究结果不仅能丰富笃斯越桔花青苷合成调控理论，而且对资源的利用及品种改良具有重要的意义。

White-fruited bog billberry is a mutant of Vaccinium uliginosum, which can't synthesize anthocyanin under low temperature stimulation. It is a good material for studying the mechanism of anthocyanin synthesis and regulation. VuMYB1, screened by our group in the early stage, is the key gene for anthocyanin synthesis and variation of skin color in white-fruited, but Its mechanism of acting and regulating pericarp coloring variation of Vaccinium uliginosum are still unclear. In this study, the promoter sequences of the white-fruited varieties and its wild type were compared, screen the upstream transcription factors by yeast one hybrid, study the promoter function and variation, elucidate the molecular mechanism of anthocyanin synthesis disorder in Vaccinium uliginosum fruit, develop molecular markers and use them in natural population identification, and study the expression of VuMYB1 and its upstream transcription factors in different light and temperature groups. The effects of transient and overexpression on anthocyanin synthesis in Arabidopsis, calli and White-fruited varieties were studied. VIGS was used to verify the effect of gene silencing on anthocyanin synthesis in wild-type fruits. Yeast two hybrid was used to screen the interacting proteins and explore the regulation of VuMYB1 interacting protein complex on structural genes of anthocyanin synthesis. The results not only enrich the theory of anthocyanin synthesis regulation of Vaccinium uliginosum, but also have important significance for resource utilization and cultivated varieties improvement.