Polysomes, Ribonucleic Acid, and Protein Synthesis During Germination of Neurospora crassa Conidia

Abstract

The level of polysomes in ungerminated conidia of Neurospora crassa depends on the method used to collect spores. Spores harvested and exposed to hydration contain 30% of their ribosomes as polysomes, whereas those not exposed to hydration contain only 3% of their ribosomes as polysomes. During the germination process, the percentage of the ribosomes which sediment as polysomes increases rapidly to a level of approximately 75% during the first 15 to 30 min of germination. This rapid increase has been shown to require a carbon source. During the first 30 min of germination, spores synthesize ribosomal ribonucleic acid (RNA) and heterogeneously sedimenting RNA, i.e., presumptive messenger RNA.