Cai Yumeng, Yin Ling, Tu Wenrui, Deng Zhefang, Yan Jing, Dong Wenjie, Gao Han, Xu Jinxu, Zhang Nan, Wang Jie, Zhu Lei, Meng Qingyong, Zhang Yali
College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China.
Tianjin Key Laboratory of Crop Genetics and Breeding, Crops Research Institute, Tianjin Academy of Agricultural Sciences, Tianjin, China.
Front Plant Sci. 2021 Nov 17;12:759047. doi: 10.3389/fpls.2021.759047. eCollection 2021.
Seedless fruits are favorable in the market because of their ease of manipulation. Sucrose transporters (SUTs or SUCs) are essential for carbohydrate metabolism in plants. Whether SUTs participate directly in causing stenospermocarpy, thereby increasing fruit quality, remains unclear. Three , namely, , , and from , were characterized and ectopic expression in tomatoes. - and -overexpressing lines had similar flower and fruit phenotypes compared with those of the wild type. -overexpressing lines produced longer petals and pistils, an abnormal stigma, much less and shrunken pollen, and firmer seedless fruits. Moreover, produced fruits from all -overexpressing lines had a higher soluble solid content and sugar concentration. Transcriptomic analysis revealed more genes associated with carbohydrate metabolism and sugar transport and showed downregulation of auxin- and ethylene-related signaling pathways during early fruit development in -overexpressing lines relative to that of the wild type. Our findings demonstrated that stenospermocarpy can be induced by overexpression of through a consequential reduction in nutrient delivery to pollen at anthesis, with a subsequent downregulation of the genes involved in carbohydrate metabolism and hormone signaling. These commercially desirable results provide a new strategy for bioengineering stenospermocarpy in tomatoes and in other fruit plants.
无籽果实因其易于处理而在市场上受到青睐。蔗糖转运蛋白（SUTs或SUCs）对植物碳水化合物代谢至关重要。SUTs是否直接参与导致单性结实从而提高果实品质，仍不清楚。从[具体植物名称]中鉴定出三个蔗糖转运蛋白，即[蛋白名称1]、[蛋白名称2]和[蛋白名称3]，并在番茄中进行异位表达。与野生型相比，过表达[蛋白名称1]和[蛋白名称2]的株系具有相似的花和果实表型。过表达[蛋白名称3]的株系产生更长的花瓣和雌蕊、异常的柱头、更少且萎缩的花粉以及更硬的无籽果实。此外，所有过表达[蛋白名称3]的株系所结的果实具有更高的可溶性固形物含量和糖浓度。转录组分析揭示了更多与碳水化合物代谢和糖转运相关的基因，并表明在过表达[蛋白名称3]的株系中，相对于野生型，在果实发育早期生长素和乙烯相关信号通路下调。我们的研究结果表明，通过在花期减少向花粉的养分输送，随后下调参与碳水化合物代谢和激素信号的基因，过表达[蛋白名称3]可诱导单性结实。这些具有商业价值的结果为番茄和其他果树中单性结实的生物工程提供了一种新策略。
