番茄果型控制基因FS8.1的克隆、功能研究及育种应用

果实形状是重要的外观品质性状。模式植物番茄的果形主要受5个位点的控制。其中fs8.1突变使圆形果变成矩形果，增强了果实的机械耐受力，利于番茄的机械化采收和运输贮藏。因而上世纪60年代以来fs8.1在育种上的应用是番茄育种特别是加工番茄育种的突破性事件。但该基因至今未被克隆。最近，我们利用混池群体测序与遗传分析相结合的策略分离了FS8.1基因，发现其编码一个转录调控因子。更重要的是，我们发现fs8.1突变还对果实的营养品质有重要贡献，可使可溶性固形物含量提高17%。在此基础上，本申请将综合采用各种分子生物学技术手段，并结合转录组、代谢组和染色质共沉淀测序等各种组学技术，从转录调控和代谢调控的角度阐明FS8.1调控果形建成和品质形成的分子作用网络。同时建立FS8.1分子标记育种和基因编辑育种技术体系，实现圆果材料和矩形果材料之间的快速转变，为番茄的外观多样化育种提供新技术、新种质。

Fruit shape is an important appearance quality trait. Five major quantitative trait loci (QTL) could explain most of the fruit shape variation of the model plant tomato. Among them, the fs8.1 mutation results in a shape change from round to blocky and thereby improves the endurance of the fruit during mechanical harvesting. Thus, since the 1960s, the application of fs8.1 is a breakthrough event in tomato breeding, especially in processing tomato breeding. However, the gene underlying fs8.1 has not been cloned. More recently, we identified the FS8.1 gene by using bulk population sequencing in combination with phenotypic analysis of the introgression lines, and found that FS8.1 encodes a transcriptional regulatory factor. More importantly, the fs8.1 mutation makes a substantial contribution to the nutritional quality of fruits, and the content of soluble solids increases by 17%. In this application, we propose to elucidate the molecular action mechanism of FS8.1 in regulating fruit shape determination and quality formation at the transcriptional and metabolic levels by using various molecular biological techniques and multi-omics strategies. Moreover, we will employ the molecular marker-assisted selection and the gene editing technology to achieve the rapid transition between round-shaped tomatoes and blocky-shaped tomatoes, and to generate new germplasms with different shape and color which would be promising materials for tomato breeding in the future.