Different Fruit-Specific Promoters Drive AtMYB12 Expression to Improve Phenylpropanoid Accumulation in Tomato

Abstract

Tomato is an economically crucial vegetable/fruit crop globally. Tomato is rich in nutrition and plays an essential role in a healthy human diet. Phenylpropanoid, a critical compound in tomatoes, reduces common degenerative and chronic diseases risk caused by oxidative stress. As an MYB transcription factor, ATMYB12 can increase phenylpropanoid content by activating phenylpropanoid synthesis related genes, such as PAL, C4H, 4CL, CHS. However, the heterologous expression of AtMYB12 in tomatoes can be altered through transgenic technologies, such as unstable expression vectors and promoters with different efficiency. In the current study, the efficiency of other fruit-specific promoters, namely E8S, 2A12, E4, and PG, were compared and screened, and we determined that the expression efficiency of AtMYB12 was driven by the E8S promoter was the highest. As a result, the expression of phenylpropanoid synthesis related genes was regulated by AtMYB12, and the phenylpropanoid accumulation in transgenic tomato fruits increased 16 times. Additionally, the total antioxidant capacity of fruits was measured through Trolox equivalent antioxidant capacity (TEAC) assay, which was increased by 2.4 times in E8S transgenic lines. TEAC was positively correlated with phenylpropanoid content. Since phenylpropanoid plays a crucial role in the human diet, expressing AtMYB12 with stable and effective fruit-specific promoter E8S could improve tomato’s phenylpropanoid and nutrition content and quality. Our results can provide genetic resources for the subsequent improvement of tomato varieties and quality, which is significant for human health.

SlMYB1regulates the accumulation of lycopene, fruit shape, and resistance toBotrytis cinereain tomato

“…With a significant increase in the gene expression at fruit developmental stages, we used a fruit-specific promoter E8 [ 34 ] linked to the coding sequence (CDS) regions of SlMYB1 to further explore the function of SlMYB1 during fruit development. We generated the transgenic lines fruit-specific expression (FE) MYB1 in the fruit ( Fig.…”

Overexpression of AtMYB12 transcription factor simultaneously enhances quercetin-dependent metabolites in radish callus

“…Notably, some secondary metabolite production genes have been altered by endogenous or exogenous overexpression of a single transcription factor [ [6] , [7] , [8] ]. For instance, the AtMYB12 gene from Arabidopsis thaliana has been found to enhance flavonoid content in tomato and upregulate flavonoid-specific genes, including phenylalanine ammonia lyase (PAL), cinnamate 4-hydroxylase (C4H), 4 Coumarate: CoA ligase ( 4CL ), chalcone synthase (CHS), flavonol synthase (FLS) [ [9] , [10] , [11] ]. When AtMYB12 was overexpressed to enhance insect resistance, it led to increased flavonol content in tomato and tobacco [ 11 , 12 ].…”

“…For instance, the AtMYB12 gene from Arabidopsis thaliana has been found to enhance flavonoid content in tomato and upregulate flavonoid-specific genes, including phenylalanine ammonia lyase (PAL), cinnamate 4-hydroxylase (C4H), 4 Coumarate: CoA ligase ( 4CL ), chalcone synthase (CHS), flavonol synthase (FLS) [ [9] , [10] , [11] ]. When AtMYB12 was overexpressed to enhance insect resistance, it led to increased flavonol content in tomato and tobacco [ 11 , 12 ]. Furthermore, the overexpression of AtMYB12 in tobacco callus culture resulted in increased rutin and quercetin production [ 13 , 14 ], as observed in hairy root buckwheat cultures as well [ 13 ].…”

<em>Agrobacterium tumefaciens</em>-Mediated Genetic Transformation of Narrowleaf Plantain

“…However, Arabidopsis can be limited as a model for species with different characteristics or unique traits 3 . This has prompted the development of new model systems, such as maize (Zea mays), an important plant for developmental genetics in monocots 4 , and tomato (Solanum lycopersicum), which is an important model for evolutionary studies, fruit development, and production, and is a good representation for vegetable crops 5 . A method for genetic transformation is a prerequisite for a plant species to serve as a model organism 2 .…”