Cloning And Transformation Of Raffinose Synthase Into Maize

Maize is an important food crop in China,however,its production is severely affected by abiotic stress,such as drought and salt.One response of plants to the abiotic stress is to accumulate a large amounts of Raffinose Family Oligosaccharides(RFOs)to adapt to the extreme environment conditions.A unique maize raffinose synthase gene(ZmRS)was cloned using homology cloning method.A prokaryotic expression vector of ZmRS was constructed.Polyclonal antibodies against ZmRS were produced from rabbits,and the antiserum was determined using western-blot.The results showed that the polyclonal antibodies can detect 10 ng of ZmRS.A eukaryotic overexpression vector of ZmRS was also constructed for maize transformation.ZmRS protein was detected in maize mesophyll protoplast when transformed with ZmRS expression vector.Then,agrobacterium-mediated method was applied for maize transformation.Immature embryos of maize inbred A188 were used for agrobacterium transformation.After selection and plant regeneration,eighteen T0 transgenic maize were obtained,and thirteen of them were fertile.PCR analysis showed that the transgene ZmRS was integrated into the maize genome.Western blot failed to detect ZmRS protein in the transgenic lines.