Submitted to: Biotechnology Letters
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/2/2004
Publication Date: 5/1/2004
Citation: Kuykendall, L.D., Upchurch, R.G. 2004. Expression in sugar beet of the introduced cercosporin toxin export gene cfp from cercospora kikuchii, the causative organism of purple seed stain in soybean. Biotechnology Letters. 26:723-727. Interpretive Summary: Cercospora-induced leafspot disease is a serious problem for sugar beet production in most of the U.S. growing regions. Thus far, only moderate resistance to this serious fungal disease has been has been developed through plant breeding and germplasm screening. Biotechnology may be of use to solve this problem since transformed plants may acquire disease resistance genes from diverse species. Even a microbial invader itself, like some phytopathogenic viruses, can serve as a source of genes encoding a new mechanism of resistance. In this study, the CFP gene from the fungus Cercospora was put into in sugar beet; that the gene was indeed active was determined using techniques known as "RT-PCR" and "Western analysis". CFP had earlier been transferred to sugar beet using so-called "transformation" by genetic exchange with special bacteria known as "Rhizobium". CFP may serve as a resistance factor in sugar beet against leafspot disease. The results of this investigation are a significant step toward determining this, and as such, will be of interest to plant molecular biologists, horticulturalists, breeders, and plant pathologists.
Technical Abstract: The Cercospora kikuchii cercosporin export gene CFP was introduced into Beta vulgaris L. by conjugation with Rhizobium radiobacter. That recombinant plants maintained the transgene during vegetative propagation was verified by PCR using CFP gene specific primers. These transgenic sugar beets matured and are producing seed. Transcriptional expression of the CFP gene in leaves was determined by RT- (reverse transcpritase) -PCR using CFP -specific primers and total cellular RNA. CFP protein production was detected using an affinity-purified polypeptide-specifc antibody with Western analysis. Further analysis of expression of CFP in sugar beet for enhancing leafspot disease resistance is planned.