Untersuchungen zur Entwicklung des PhycomycetenAllomyces arbuscula

InAllomyces arbuscula formation of gametes occurs within 80 min in isolated gametangia. Gametogenesis shows to be sensitive to cycloheximide at 50 and 100 g/ml, while actinomycin D at 25 and 50 g/ml fails to inhibit gametogenesis. Synthesis ofrRNA can be profoundly inhibited by 3×10^-3 M 5-fluorouracil prior to gametogenesis, without any effect on differentiation of gametes. It is shown by polyacrylamide-gel electrophoresis that during gametogenesis radioactive phosphate is incorporated intotRNA, but not intorRNA. The results indicate that formation of gametes is dependent uponmRNA already present in the gametangia before induction of gametogenesis. It is concluded further that protein synthesis on cytoplasmic ribosomes is finished 20–30 min after induction and thatrRNA synthesis seems not to be a prerequisite for the differentiation of gametes.