Genetic analysis of the structure and function of RNase P from E. coli.

A brief review of the genetic studies on ribonuclease P (RNase P) from Escherichia coli is presented. Temperature-sensitive mutants of E. coli defective in tRNA processing were isolated by screening cells which were unable to synthesize a suppressor tRNA at restrictive temperature. Structural analysis of accumulated tRNA precursors showed that the isolated mutants were defective in RNase P activity. Analyses of the mutants revealed that the enzyme is essential for the synthesis of all tRNA molecules in cells and that the enzyme consists of two subunits. Analyses of the isolated mutants revealed a possible domain structure of the RNA subunit of the enzyme.