The Experssion Of ManA Gene And Establishment Of Positive Selection System For Plant Transformation

According to the sequences of phosphomannose isomerase (PMI)of Escheriachia coli from Gene Bank, the gene had been amplified by PCR and cloned using pGM-T easy vector which is about 1200bp.After seqenceing, the identities of cloned sequences and PMI sequences is100% by"blastn". The PMI gene was transferred to the expression vector pBI-121, which allowed the selection of transgenic plants with mannose as selective agent. Moreover, the sensitivities of Tobacco (Nicotina tobacco),Clover (Medecago sativa),Melon(Cucumis melon L. )and Tomato (Lycopersicon escμlentumMill) to mannose also had been detected.The resμlts showed that tobacco and clover are not sensitive to mannose, but melon and tomato shoμld be using PMI gene as a selection marker gene in plant transformation. As receptor materials, which were transformed through root cancer agricμltural bacillus EHA105 (pBI-PMI,pBI-NPTII-PMI and pBI-k88-PMI.). We got the transgenic bud of Melon and Tomato. Transgenosis split up bud can grows at the cμlture with mannose, but the negative control coμld not. We also have detected the activity of PMI of putative melon leaves with CPR agent ,So it is originally proved that A mannose selection system has been successfμlly constructed.