Effect of Ectopic Expression of AtCKX2 Gene on the Development of Tomato (Solanum lycopersicum) Fruits
LIU Xue-Xia1, LI Hu2, DONG Ying-Hua1, WU Han2, GAN Li-Jun1, *
1 College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China; 2 College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
Abstract：Tomato (Solanum lycopersicum) is one of the most widely grown vegetables in the world. It is a model crop for studying the development of climacteric fruits. Various plant hormones are involved in regulating the growth and development of tomato fruits. Cytokinins can promote cell division of fruit, make fruit larger, increase fruit weight, delay fruit senescence, and increase fruit yield. In order to study the effect of endogenous cytokinin on tomato fruits, the expression vector for the tomato fruit-specific promoter Tfm7 to drive the Arabidopsis thaliana cytokinin oxidase 2 gene (AtCKX2) was constructed. The transgenic plants were obtained by the method of Agrobacterium tumefaciens transformation. The transgenic plants were verified by the specific primers of the promoter Tfm7 and the target gene AtCKX2. The PCR results indicated that the promoter Tfm7 and the target gene AtCKX2 had been transferred into the tomato plants. The results of qRT-PCR showed that the AtCKX2 gene was not expressed in the leaves of tomato plants and was expressed in the pollen flowers. The expression level of AtCKX2 gene was the highest in the fruit 5 d after pollination. As the fruit developed, the expression level of AtCKX2 gene gradually decreased, and it was hardly expressed in the late stage of fruit development. Studies on tomato fruits showed that compared with wild-type tomato fruits, the content of endogenous cytokinin zeatin (ZT) and isopentenyladenine (iP) in transgenic tomato fruits decreased, the single fruit weight, vertical and horizontal diameter of transgenic fruits decreased, and the content of soluble sugar and soluble protein in fruits decreased, the content of titratable acid increased. These results indicate that endogenous cytokinins can affect the growth and development of tomato fruits. This study provides new ideas for the role of cytokinins in fruit development.
刘雪霞, 李虎, 董映华, 吴寒, 甘立军. 异源表达AtCKX2基因对番茄果实发育的影响[J]. 农业生物技术学报, 2020, 28(3): 399-406.
LIU Xue-Xia, LI Hu, DONG Ying-Hua, WU Han, GAN Li-Jun. Effect of Ectopic Expression of AtCKX2 Gene on the Development of Tomato (Solanum lycopersicum) Fruits. 农业生物技术学报, 2020, 28(3): 399-406.
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