Gene cloning of melon sucrose phosphate synthase and construction of plant engineering vector

Sucrose- phosphate synthase is the critical synthase of sucrose synthetic route in melon fruits. The aim of this experiment is to clone it and introduce into low carbohydrates melon self-bred line for creating new and good species of high quality fruit. By means of RT-PCR and Southern blot methods, we have cloned the 5’ end 2 859 bp and 3’ end 852 bp fragments of melon sucrose- phosphate synthase gene from the total RNA in seedling leaves. Recombinant plasmids were identified through digested by restriction enzyme,PCR and compared sequences homology. Using Taq pclymerase PCR to splicing the full sequences cDNA, this fragment of 3 692 bp had 97% to 99% homology to other plant gene of GenBank. Its registered code was DO364058. The linearity fragments of the binary plant expression vector pROK2 and gene ligase were obtained. By T4 ligase,the sense cDNA of SPS gene was inserted between CaMV35S promoter and Tnos terminator. The sense expression vector with NPT-Ⅱwas named pROK-SPS.