ABSTRACT
Soybean beta-1,3-endoglucanase represents a model system for studies on early plant responses to infection by fungal pathogens, and it has been implicated in the release of elicitors from fungal cell walls. In the present study, potato plants were transformed with the soybean beta-1,3-endoglucanase cDNA via Agrobacterium delivery system. The transfer of the gene into potato genome was confirmed by (i) PCR amplification, (ii) Northern blot analyses, and (iii) an increase in the activity of beta-1,3-endoglucanase in transgenic plants. The transformation resulted in an increased resistance of selected transgenic plants to infection by Phytophthora infestans, an important pathogen.
Subject(s)
Glycine max/genetics , Phytophthora/pathogenicity , Solanum tuberosum/genetics , beta-Glucosidase/genetics , Base Sequence , DNA Primers , Glucan 1,3-beta-Glucosidase , Phytophthora/growth & development , Plants, Genetically Modified , Solanum tuberosum/microbiology , Glycine max/enzymologyABSTRACT
The nuclear gene NAM9 from Saccharomyces cerevisiae (Sc) codes for a protein which, on the basis of sequence homology, was previously postulated to be a mitochondrial (mt) equivalent of the Escherichia coli (Ec) S4 ribosomal protein (r-protein) [Boguta et al., Mol. Cell. Biol. 12 (1992) 402-412]. The mt-r character of the NAM9 product is now confirmed by cross-reaction with the antisera for the Sc mt r-proteins. The NAM9-1 mutation, characterized previously as the nuclear suppressor of some ochre mt mit- mutants, is found to be a single nucleotide substitution changing Ser82 to Leu within the part of NAM9 corresponding to the S4 region involved in interaction with the 16S rRNA. This indicates that the mechanism of NAM9-1 suppression could be analogous to the suppression due to ram (ribosomal ambiguity) mutations in the Ec structural gene encoding r-protein S4. The NAM9-1 mutation leads also to defect in respiratory growth in the background of the wild-type mit+ genome.
