RESUMEN
The effects of the preparation Furolan, (2-furyl-2)-1,3-dioxolane, on the degree of mRNA polyadenylation and the pattern of protein synthesis in the ripening grain of several soft winter wheat (Triticum aestivum L.) cultivars were studied. It was demonstrated that Furolan stabilized mRNA in a cultivar-specific manner, thereby accelerating to various degrees the biochemical processes taking place in the ripening grain. Of the wheat cultivars studied, Krasnodarskaya 99 was the most responsive cultivar with respect to a set of changes in nucleic-protein metabolism; the cultivar Deya was next followed by the cultivar Bat'ko. The cultivar Kroshka did not respond to the treatment with Furolan. The cultivar specificity of this preparation allows its practical application to be optimized.
Asunto(s)
Productos Agrícolas/efectos de los fármacos , Dioxolanos/farmacología , Furanos/farmacología , Poliadenilación/efectos de los fármacos , Estabilidad del ARN/efectos de los fármacos , ARN de Planta/efectos de los fármacos , Triticum/efectos de los fármacos , Productos Agrícolas/genética , Productos Agrícolas/metabolismo , Grano Comestible/efectos de los fármacos , Grano Comestible/genética , Grano Comestible/metabolismo , Proteínas de Plantas/análisis , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Biosíntesis de Proteínas/efectos de los fármacos , ARN de Planta/metabolismo , Triticum/genética , Triticum/metabolismoRESUMEN
The effect of field drought on gene expression in developing Zea mays L. grain and the influence of the imbalance of essential amino acids on the expression of genes in white-rat liver at the mRNA stability level were studied. A special ommp system, which included incubation (65 degrees C, 5 min) of an aqueous preparation of highly purified, high molecular-weight RNA isolated in the presence of Mg2+, was used for the analysis of mRNAs relative stability in eukaryotes. Drought changed the relative stability of seven specific mRNA in the maize developing grain: there occurred a considerable stabilization of the eEF-1 alpha mRNA and, conversely, a destabilization of the 19-kDa zein mRNA. The imbalance for lysine and tryptophan reduced the stability of the total polyadenylated mRNA and the eEF-1 alpha mRNA of rat liver. The mRNA stability positively correlated with animal growth. Thus, using the ommp system, the effect of stressful factors on the stability of specific mRNA in eukaryotes--depending on mRNA species, stressful factors, and the tissue--was shown.
Asunto(s)
Procesamiento Postranscripcional del ARN , ARN Mensajero/genética , Estrés Fisiológico/genética , Triticum/genética , Zea mays/genética , Animales , Lisina/metabolismo , Modelos Genéticos , Ratas , Triptófano/metabolismoRESUMEN
The lifetime of the zein mRNA in a developing corn (Zea mays L.) kernel under genome transcription blockade with actinomycin D (in vivo) and in a cell-free system (in vitro) was studied. After a 10 h blockade of gene transcription with actinomycin D, only 55% of 19 kDa zein mRNA and 40% of 22 kDa mRNA were detected in a developing kernel of normal corn. In that of the opaque-2 mutant 80% of 19 kDa zein mRNA remained. To examine the relative stability of poly(A)-containing mRNA, cell-free systems from rabbit reticulocyte lysate and wheat-germ extract were used. In both cases only 40% of 19 kDa zein mRNA and 60% of 22 kDa zein mRNA decayed during a 30 min incubation. Differential mRNA degradation of poly(A)-containing zein mRNA was observed on affinity chromatography; poly(A)-containing 19 kDa zein mRNA from normal corn partially decayed by elution from poly(U)-Sepharose whereas that from opaque-2 remained stable. These data suggest that differential mRNA stability is an important factor in the regulation of the zein gene expression in a developing corn kernel.