Clone Of Plant Aminotransferases Genes (eR Genes) And Transformation In Cucumber

Downy mildew caused by the oomycete pathogen Pseduopemnospora cubensis is a devastating foliar disease of cucurbits worldwide. It breaks distant hybridization compitable and discover a new breeded way. In this paper, two eR genes(H-At2, T-At2 genes)were cloned from cucumber and melon, and for H-At2 was cloned fromcucumber firstly. The genes were transforred to cucumber in order to receive new cucumber breeding materials. GENBANK of H-At2, T-At2 are EF628204 and EF628205. GENBANK of H'-At2,T'-At2 are EF628206 and EF628207.Here, we show that unlike other plant disease resistance genes, which confer an ability to resist infection by pathogens expressing corresponding avirulence genes, the resistance of PI to P. cubensis is controlled by enhanced expression of the enzymatic resistance (eR) genes Atland At2. These constitutively expressed genes encode the photorespiratory peroxisomal enzyme proteins glyoxylate aminotransferases. Our previous genetic results suggested that cloning of this enzymatic protein into a susceptible genotype of melon turned t highly resistant to downy mildew. The genes that encode this protein control enhanced enzymatic activity of the host and therefore are designated here as enzymatic resistance (eR) genes. In this paper, we cloned At2 genes by RT-PCR technology from cucumber and melone. Genes were transforfered cucumber using Pollen-tube pathway. It establish the high efficiency express vector which instead of 35s promoter f plant express vector PROK2 by tissue specificity promoter PNZIP called PPN. And the plant express vector which PNZIP promoter transduction At2gene, called PPN-At2. We received transgenic plants which PPN-At2 transforred cucumber. The results as fellows:1) In this paper aminotransferase 2(At2 genes) were cloned and plant express vector were constructed. H-At2 T-At2 genes fragments were amplified by RT-PCR method which reversed from total RNA of cucumber and melon through designing primer according to at2 gene of melon(Af461048), then linked into the PGEM-T easy vector. The result revealed that it was highly homologous to At2 genes of reported.2) Construction the plant high efficiency express vector(PPN) and plant expression vector (PPN-At2) which include At2 genes. H-At2 and T-At2genes fragments were cut from recombined plasmid by Scaâ… and Scaâ…¡, and insert into plant expression vectors after PNZIP promoter. PPN-At2 formed.3) Cucumber transformation test was carried for bellow genes by Pollen-tube pathway. PPN-At2 genes were transducted into cucumber inbred line. On the basis of KN filtering, PCR method was used to decetion. As a result five genetic plants received, the transformation rate of cucumber was 2-3/10000. Pollen-tube pathway has broaden the approach of transformation.