ABSTRACT
Primary transformants of SR1 Nicotiana tabacum plants with RNA interference-based silencing of the gene for extracellular ribonuclease Nk1 were constructed. It was demonstrated that the profiles of ribonuclease activities of leaf protein extracts from these plants lacked ribonuclease with electrophoretic mobility corresponding to that of the Nk1 protein. Primary transformants did not differ phenotypically from control plants. They represent a new model for investigation of the biological role of extracellular ribonucleases, including the molecular mechanisms of resistance to pathogens.
Subject(s)
Gene Silencing , Nicotiana/genetics , Ribonucleases/genetics , Plant Diseases/genetics , Plant Leaves/anatomy & histology , Plant Leaves/enzymology , Plant Leaves/genetics , RNA Interference , Nicotiana/anatomy & histology , Nicotiana/enzymologyABSTRACT
Complementary DNA for the extracellular RNase of Zinnia elegans was cloned under control of the cauliflower mosaic virus 35S RNA constitutive promoter and transferred into the Nicotiana tabacum SR1 plants. Primary tobacco transformants were characterized by a high level of RNase activity.
Subject(s)
Asteraceae/enzymology , Extracellular Fluid/enzymology , Nicotiana/enzymology , Plants, Genetically Modified , Ribonucleases/biosynthesis , Transformation, Genetic , Genes, Reporter , Kanamycin Kinase/biosynthesis , Kanamycin Kinase/genetics , Ribonucleases/genetics , Nicotiana/geneticsABSTRACT
The distribution and accumulation of soybean mosaic virus antigen in the leaves of sensitive plants with well expressed mosaic symptoms and symptomless tolerant soybean plants Glycine max (L.) Merr. were similar. Low concentration of virus antigen was found in extremely resistant soybean plants in mechanically inoculated leaves and those of the 2-4 circles two-three weeks after inoculation but 5 weeks later the virus antigen was detected only in the top leaves.
Subject(s)
Antigens, Viral/analysis , Glycine max/virology , Mosaic Viruses/pathogenicity , Plant Diseases/virology , Mosaic Viruses/immunology , Plant Leaves/virology , Precipitin Tests , Time FactorsABSTRACT
The firmly bound protein VPg was found to be linked to the phenol-deproteinized virion RNAs of radish mosaic virus. This protein was specifically labelled with the [125I]-Bolton-Hunter reagent in vitro. The molecular weight of VPg as determined by SDS-PAAG electrophoresis is equal to 4000. It was assumed that VPg is covalently linked to the 5'-end of radish mosaic virus RNAs.
