The Stability of Messenger Ribonucleic Acid during Sporulation in Bacillus subtilis

The stability of postlogarithmic mRNA has been assessed in Bacillus subtilis during sporulation time periods. The appearance of refractile bodies, alkaline phosphatase synthesis, and total protein synthesis is controlled by mRNA which has an estimated half-life of less than 10 min. Inhibition of RNA synthesis at various times by rifampin addition or temperature shift with a temperature-sensitive RNA polymerase mutant demonstrates that postlogarithmic mRNA is unstable and that continuous RNA synthesis is necessary for expression of the developmental sequence. The addition of chloramphenicol also inhibits the appearance of refractile bodies and alkaline phosphatase synthesis, suggesting that these processes require de novo protein synthesis.