Effects Of AcPDS1 Gene On Fruit Quality Of Transgenic Tomato

The ripening and development of tomato fruit is accompanied by the biosynthesis and decomposition of many metabolites.Carotenoids biosynthesis is one of the most important metabolic pathways.Carotenoids is organic pigment,widely existing in nature.Carotenoids can represent many beneficial functions for human health.Due to its decomposition in vitro,we need to absorb the necessary carotenoids from fruits and vegetables.Many genes are involved in the process of the biosynthesis of carotenoids.Moreover,each gene plays an indispensable role.In the pathway,PDS(phytoene dehydrogenase)regulates the dehydrogenation of phytoene to form lycopene,which is an important speed-limiting enzyme in the biosynthesis pathway.In this study,AcPDS1 gene sequence was cloned.We performed detailed studies as described below.Firstly,the plant transient expression vector of AcPDS1 was injected into tobacco leaves.The western blot was used to detect the expression of AcPDS1 in tobacco leaves.Secondly,the over-expression vector of AcPDS1 gene was constructed and transformed into tomato by Agrobacterium tumefaciens-mediated stable genetic transformation.The fruits of AcPDS1 transgenic tomato were analyzed in the following aspects: phenotype analyses,metabolites determination,and detection of carotenoids biosynthesis related genes' expression.The results showed that after transient expression,the AcPDS1 protein in tobacco leaves was detected by western blot.The largely increasion of ?-carotene content in tobacco leaves was detected by HPLC.The subcellular localization of PDS protein was confirmed by laser confocal microscopy.Trough Agrobacterium tumefaciens-mediated infection,the AcPDS1 transgenic tomato plants were generated.The contents of lycopene and ?-carotene in transgenic plants were higher than those in wild-type tomato fruits,detected by high performance liquid chromatography(HPLC).The expressions of carotenoids biosynthesis related genes and ethylene-response genes were influenced in AcPDS1 transgenic tomato fruits.This study can provide a good foundation for further exploring the detailed molecular function of AcPDS1 gene in carotenoids synthesis pathway.