Du Hui, Zhai Zefeng, Pu Jin, Liang Jun, Wang Rongyan, Zhang Zhong, Wang Pei, Zhu Yanhui, Huang Lian, Li Dawei, Chen Kaiyuan, Zhu Guangtao, Zhang Chunzhi
Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Synthetic Biology, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China.
Yunnan Key Laboratory of Potato Biology, The AGISCAAS-YNNU Joint Academy of Potato Sciences, Yunnan Normal University, Kunming, China.
Plant Biotechnol J. 2025 May;23(5):1521-1534. doi: 10.1111/pbi.14602. Epub 2025 Jan 30.
Anthocyanin biosynthesis and accumulation determines the colour of tuber flesh in potato (Solanum tuberosum) and influences nutritional quality. However, the regulatory mechanism behind anthocyanin biosynthesis in potato tuber flesh remains unclear. In this study, we identified the Pigmented tuber flesh (Pf) locus through a genome-wide association study using 135 diploid potato landraces. Genome editing of two tandem R2R3 MYB transcription factor genes, StMYB200 and StMYB210, within the Pf locus demonstrated that both genes are involved in anthocyanin biosynthesis in tuber flesh. Molecular and biochemical assays revealed that StMYB200 promotes StMYB210 transcription by directly binding to a 1.7-kb insertion present in the StMYB210 promoter, while StMYB210 also regulates its own expression. Furthermore, StMYB200 and StMYB210 both activated the expression of the basic helix-loop-helix transcription factor gene StbHLH1 and interacted with StbHLH1 to regulate anthocyanin biosynthesis. An analysis of the StMYB210 promoter in different diploid potato accessions showed that the 1.7-kb insertion is associated with flesh colour in potato. These findings reveal the genetic and molecular mechanism by which the Pf locus regulates anthocyanin accumulation in tuber flesh and provide an important reference for breeding new potato varieties with colourful flesh.
花青素的生物合成与积累决定了马铃薯（Solanum tuberosum）块茎肉的颜色，并影响其营养品质。然而，马铃薯块茎肉中花青素生物合成背后的调控机制仍不清楚。在本研究中，我们通过对135份二倍体马铃薯地方品种进行全基因组关联研究，鉴定出了色素块茎肉（Pf）位点。对Pf位点内两个串联的R2R3 MYB转录因子基因StMYB200和StMYB210进行基因组编辑，结果表明这两个基因均参与块茎肉中花青素的生物合成。分子和生化分析表明，StMYB200通过直接结合StMYB210启动子中存在的一个1.7 kb插入片段来促进StMYB210的转录，而StMYB210也调控其自身的表达。此外，StMYB200和StMYB210均激活了碱性螺旋-环-螺旋转录因子基因StbHLH1的表达，并与StbHLH1相互作用来调控花青素的生物合成。对不同二倍体马铃薯材料中StMYB210启动子的分析表明，1.7 kb插入片段与马铃薯块茎肉颜色相关。这些发现揭示了Pf位点调控块茎肉中花青素积累的遗传和分子机制，为培育具有彩色块茎肉的马铃薯新品种提供了重要参考。
