Identification Of Parthenocarpic Differentially Expressed Sequences And Initial Function Analysis Of SmMsrA Gene In Eggplant

Eggplant(Solanum melongena L.) is a warm season vegetable. In protected out-of-season and spring early maturing cultivation, low temperature and weak light environment often induced difficult pollination fertilization, flower and fruit drop increased, lower yield and economic benefits. However, parthenocarpic eggplant can partly overcome adverse environmental conditions caused by fallen petal fruit drop, increase fruit-bearing rate, reduce the cost of cultivation and improve fruit quality. Eggplant parthenocarpy is of great significance to cultivate early maturity, resistant low temperature and high quality new eggplant varieties. The experimental material were the parthenocarpic line D-10 and non-parthenocarpic line 03-2. Using the real-time fluorescent quantitative PCR(q RT-PCR) technology identificated parthenocarpy related differentially expressed sequences from the SSH-c DNA libraries. Constructed VIGS and RNAi expression vectors of Sm Msr A gene basing on the cloning of eggplant methionine sulfoxide reductase gene(Sm Msr A) c DNA sequence. Analyze the preliminary function of Sm Msr A gene. The main results were summed as follows:1. The experimental material were the parthenocarpic line D-10 and non-parthenocarpic line 03-2. Using the q RT-PCR technology detected the relative expression of 95 Unique ESTs, which form SSH-c DNA liabries. The results showed that in 4 d and 6 d two periods the ratio of relatived expression of D-10. There were more sequences of the up-regulated relatived expression in the 4d and 6d. The higher relative expression ESTs probably had an important role for the parthenocarpic fruit-bearing, growth and development. 31 ESTs were significant differences of the relative expression in the eggplant fruits(ovary) development. 17 ESTs were up-regulated of the relative expression and 14 ESTs were down-regulated of the relative expression. There were five sequences related to resist low temperature, seven sequences associated with plant hormone metabolism. Further more, some sequences were related to the synthesis of protein and carbohydrate in plant metabolic processes. The sequences of resist low temperature stress and plant hormone metabolism probably interacted with the synthesis of protein and carbohydrates related sequences. They regulated the development of parthenocarpic fruit.2. The coding sequence of methionine sulfoxide reductase A(Sm MsrA) was amplified from eggplant(Solanum melongena L.) parthenocarpic line D-10 using reverse transcription polymerase chain reaction(RT-PCR) method. Through the Gateway recombination technology, we constructed three TRV-mediated VIGS expression vectors, p TRV2-Sm Msr Ai, containing different fragments of Sm Msr A gene. The VIGS expression vectors were transformed into Agrobacterium strain GV3101, and then inoculated eggplant leaves by Agro-syringe. Phenotypes observation, TRV molecular detection and q RT-PCR thechnology were used to observe and evaluate the VIGS system for silencing the Sm Msr A gene effection. The results showed that the positive control of silencing reporter gene PDS showed photo-bleaching phenotype in eggplant leaves; Silencing Sm Msr A gene were observed pale yellow(mosaic) leaves and bore smaller fruits; The expression of Sm Msr Agene was decreased obviously in the leaves and fruits of the infected eggplant plants. These results suggested that the Sm Msr A gene was a related gene in positive regulation of fruit development in eggplant.3. Through the gateway homologous recombination technology, constructed three RNAi expression vectors, p Hellsgate12-Mi, containing different fragments of Sm Msr A gene. The RNAi expression vectors were detected exactly by microbial PCR and sequencing. p Hellsgate12-Mi were transformed into Agrobacterium strain C58. It identificated a fundation for further in-depth study the function and regulation of Sm Msr A gene in fruit development.