Sequential Biosynthesis of Ribonucleic Acids During Germination of Teliospores ofUstilago Maydis

Abstract

During germination, teliospores of Ustilago maydis synthesized RNA and protein. The three common RNA species were synthesized in the following order: rRNA, tRNA, and material corresponding to mRNA.2 The synthesis of mRNA was indicated by the formation of polyribosomes which appeared relatively late as a fast-moving peak that sedimented before the monosome peak in a sucrose density gradient centrifugation. These polysomes contained nucleic acids and protein, and were hydrolyzed by RNase so that only monosomes could be detected. Protein synthesis also appeared late and was correlated with the time that the polyribosomes could first be detected.