Preliminary Analysis Of ACS And ETR Gene Function In Vitis Vinifera

Grape storage period is shot,and phenomeon such as berry drop,rot,dry rachis,browning,is normally observed in the process of storage and distribution.Ethylene plays an important role in many processes of fruit physiological changes after harvest,and is one of important reasons,which effects berry drop and physiological changes.ACS gene and ETR gene is the key gene in the ethylene biosynthesis and signal transduction process.In this study,three VvACS genes and three VvETR genes were over-expressed in tomato(Solanum lycopersicum'Money maker')by Agrobacterium mediated method.In order to dicuss influences of over-expression of VvACS genes and VvETR genes on tomato,some physiological indexs were analyzed in transgenic tomatos,and functions of VvACS genes and VvETR were prelimaryly predicted.The main results are as follows:1.In this study,tomato cotyledons were used as explants,and VvACS1,VvACS2,VvACS8,VvETR1,VvETR2,and VvETR4 genes were over-expressed in tomato by Agrobacterium mediated method.The results showed that the maximum transformation efficiency was 11.69%when cell density was OD600 0.4 with 10 minutes of infection.2.Nine Km-resistant tomato lines with VvETR1 and VvETR2 genes,seven lines with VvETR4 gene,twelve lines with VvACS1 and VvACS8 genes,thirteen lines with VvACS2 gene were obtained in our study.PCR and RT-PCR analysis indicated that VvETR1,VvETR2,VvETR4,VvACS1,VvACS2,and VvACS8 genes were over-expressed in three,three,two,one,three,and six transgenic tomato lines,respectively.3.Vegetative growth of tomato was influenced by over-expression of VvACS and VvETR gene.Height of transgenic tomato lines with VvACS gene and VvETR gene were less than that of non-transgenic tomato plants in both seedling stage and mature period,and transgenic plants were shown to be dwarf in varying degrees.The less height of ACS8-8 transgenic tomato lines in mature period,which was 30%lower than that of the controls,was observed.Over-expression of VvACS8 gene in tomato obviously promoted formation of lateral buds in the stage of young plants,and numbers of mean lateral buds per plants were increased from 0.5 to 5.4.Reproductive growth of tomato was also influenced by over-expression of VvACS and VvETR gene.Compound inflorescences of transgenic plants were induced by over-expression of VvETR1,VvETR2,and VvACS8 genes,and rate of compound inflorescences of transgenic plants was increased by 1.74-3.83 fold.However,rate of compound inflorescences of transgenic plants with VvETR4,VvACSl,and VvACS2 gene was slightly lower or similar compared with that of the controls.Length of rachis in transgenic tomato lines with VvACS and VvETR genes was shorter than that of the controls,and mean length of rachis of ACS8-9 transgenic tomato lines was shorter by 69.23%.Transgenic tomatos plants with over-expression of VvACS genes were blooming 7-11 days earlier,while no obvious effects were observed on the starting date of flower of transgenic tomato lines with VvETR genes.5.Chlorophyll degradation in tomato mature fruits was inhibited by over-expression of VvACS and VvETR genes,since chlorophyll content of transgenic tomato fruits with VvACS and VvETR genes decreased compared with that of the controls.Chlorophyll content of non-transgenic tomato fruits was higher by 1.24-2.76 fold than that of fruits with over-expression of VvETR genes,and higher by 4.30-19.71 fold than of fruits with over-expression of VvACS genes.