Abstract
Actinomycin D inhibited the synthesis of poly(A)-containing messenger RNA in healthy soybean (Glycine max [L.] Merr. cv. Harosoy 63) hypocotyls and in hypocotyls inoculated with the pathogenic fungus Phytophthora megasperma var. sojae A. A. Hildb., but had little effect on protein synthesis within 6 hours. Blasticidin S, conversely, inhibited protein synthesis in the hypocotyls without exhibiting significant effects on messenger RNA synthesis. The normal cultivar-specific resistance of the Harosoy 63 soybean hypocotyls to the fungus was completely diminished by actinomycin D or blasticidin S. The fungus grew as well in hypocotyls treated with either inhibitor as it did in the near isogenic susceptible cultivar Harosoy, and production of the phytoalexin glyceollin was concomitantly reduced. The effects of actinomcyin D and blasticidin S were pronounced when the treatments were made at the time of fungus inoculation or within 2 to 4 hours after inoculation, but not after longer times. These results indicated that the normal expression of resistance to the fungus and production of glyceollin both required de novo messenger RNA and protein synthesis early after infection. Furthermore, actinomycin D and blasticidin S also were effective in suppressing resistance expression and glyceollin production in soybean hypocotyls when inoculated with various Phytophthora species that were normally nonpathogenic to the plants. This indicated that the mechanism of general resistance to these normally nonpathogenic fungi also involves de novo messenger RNA and protein synthesis and production of glyceollin.
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- Hadwiger L. A., Jafri A., von Broembsen S., Eddy R. Mode of Pisatin Induction: Increased Template Activity and Dye-binding Capacity of Chromatin Isolated from Polypeptide-treated Pea Pods. Plant Physiol. 1974 Jan;53(1):52–63. doi: 10.1104/pp.53.1.52. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hadwiger L. A., Schwochau M. E. Specificity of deoxyribonucleic Acid intercalating compounds in the control of phenylalanine ammonia lyase and pisatin levels. Plant Physiol. 1971 Mar;47(3):346–351. doi: 10.1104/pp.47.3.346. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Vance C. P., Anderson J. O., Sherwood R. T. Soluble and cell wall peroxidases in reed canarygrass in relation to disease resistance and localized lignin formation. Plant Physiol. 1976 Jun;57(6):920–922. doi: 10.1104/pp.57.6.920. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Vance C. P., Sherwood R. T. Regulation of lignin formation in reed canarygrass in relation to disease resistance. Plant Physiol. 1976 Jun;57(6):915–919. doi: 10.1104/pp.57.6.915. [DOI] [PMC free article] [PubMed] [Google Scholar]