Macromolecular synthesis during conjugation in yeast.

Morphological changes and synthesis of DNA, RNA and protein during conjugation of Saccharomyces cerevisiae was studied. It was found that during conjugation distinct cell expansion and increase in the dry mass of the cell takes place. DNA synthesis is inhibited during mating while synthesis of RNA and protein is not affected. Conjugation of temperature sensitive mutant defective in elongation of DNA chain was normal both in permissive and restrictive temperature. Conjugation of mutants defective in the initiation of DNA synthesis or defective in RNA and protein synthesis was inhibited in restrictive temperature. The results obtained with temperature sensitive mutants suggest that RNA and protein synthesis is necessary for mating reaction while DNA synthesis is not required.