Ectopic overexpression of AcMYB110 causes significantly increased content of anthocyanins in Solanum nigrum

Solanum nigrum L. is an annual undomesticated berry plant of Solanaceae. The fruits of S. nigrum are tiny, but there are about 25 seeds in a single fruit. The total number of seeds produced in one plant can reach more than 3 000. The height is about 30 -40 cm, and the whole growth cycle is two months when S. nigrum was cultivated in the light incubator of the laboratory. The Agrobacterium tumefaciens-mediated transformation has been established in S. nigrum. So S. nigrum has the characteristics of model plants. AcMYB110, an R2R3-MYB transcription factor from kiwi (Actinidia spp.), was transformed into S. nigrum mediated by A. tumefaciens. The results indicated that the petals of 35S:AcMYB110 S. nigrum plants are pink compared with white petals in wild-type plants, and content of anthocyanins was significantly increased in the pericarp from young fruit to its maturity, especially in the central part of the fruit flesh. The results showed that the ectopic expression of AcMYB110 in S. nigrum is consistent with the expression of AcMYB110 in kiwi. This suggests that AcMYB110 plays a conserved role in regulating anthocyanins synthesis in fruits and can be potentially applied for improvement of the anthocyanins content in horticulture fruits breeding.