The Study On The Lectin Gene SSL-6 Of Sclerotinia Sclerotiorum Isolated From Brassica Napus

Sclerotinia sclerotiorum(Lib.)de Bary resulting in sclerotinia is a saprophytic fungal pathogen and a serious disease lowering the yield and quality of rapeseed.In order to further study the the pathogenic mechanism of Sclerotinia sclerotiorum,we investigated the gene coding a secretory lectin in the liquid exudate droplets of the sclerotia,hoping to get new insight into the pathogenesis.In this study,we first carried out the bioinformatic analysis of SSL-6 protein and gene;then we cloned the SSL-6 gene and constructed the plant binary expression vector.The binary expression vector was transferred into Arabidopsis thaliana and rapeseed via Agrobacterium tumefaciens-mediated transformation,and the resistance inoculation test of transgenic Arabidopsis plants was finished.The main results are as follows:1.The phylogenetic tree of SSL-6 homologous animo acid have been constructed.It was speculated that SSL-6 protein was a hydrophobic secretory lectin with a typical fungal lectin AFL1 six-leaf fan structure,It is belongs to fungal fucose-specificity lectin.2.Cloning the SSL-6 ORF from Sclerotinia sclerotiorum and successfully constructing a pCAMBIA1303-SSL-6 binary expression vector.3.Obtaining T4 generation homozygous transgenic Arabidopsis with SSL-6 gene over-expression.The transgenic validity was confirmed from two levels of transcription and translation,and it was also proved that transgenic plants with SSL-6 gene could significantly improve the resistance to Sclerotinia sclerotiorum.4.Obtaining more than 20 SSL-6 transgenic rapeseed plants.After RT-PCR detection,the results showed that transgenic plants have different expression levels of SSL-6 gene.