A characterization of Tetrahymena mRNA by in vitro translation: The effects of culture growth on the recruitment of poly (A)(+) and poly (A)(-) RNA.

Messenger RNA was extracted from exponentially growing and from stationary cultures of Tetrahymena thermophila. It was separated into polyadenylated and non-polyadenylated fractions which were used as templates in a rabbit reticulocyte protein synthesizing system. The translated proteins were analysed by one and by two dimensional electrophoresis. Our experiments were intended to answer the question to which extent the abundance and the specificity of mRNA facilitates or accompanies the passage of cells through one culture growth cycle. As illustrated by the identification of 113 proteins very few differences between translated messages accompany the transition to the stationary phase, the most obvious feature being a change in the intracellular location of translation activities. These data are discussed with special reference to the prevailing occupation of Tetrahymena which is biomass production.