Messenger RNA half-life in Dictyostelium discoideum

Messenger RNA half-life in vegetatively growing cells of Dictyostelium discoideum was determined using a uridine pulse-chase procedure. In these experiments, mRNA decayed in a complex fashion, and consisted of at least two major components, one with a half-life of about 50 min and a second with a half-life of about 10 hr. These results independently confirm our previous studies on the decay of mRNA extracted from actinomycin D-treated cells. Since these results were in apparent conflict with half-life determinations obtained with a combination of actinomycin D and daunomycin (J. P. Margolskee and H. F. Lodish, 1980a, Dev. Biol. 74, 37-49), we have also studied mRNA half-life in cells treated with a combination of both drugs and found that simultaneous use of both drugs leads to accelerated mRNA decay and other noticeable side effects. In light of our observations, we have suggested an alternative to conclusions drawn by others with respect to mRNA synthesis and stability in Dictyostelium development.