Polyadenylated mRNA in Escherichia coli: Modulation of poly(A) RNA levels by polynucleotide phosphorylase and ribonuclease Ⅱ

摘要

The effect of 3'-exoribonucleases on the polyadenylation of mRNA in Escherichia coli was studied by comparing the synthesis and levels of poly(A) RNA in wild-type E coli and mutant strains defective in the two major 3'-exoribonucleases: polynucleotide phospho- rylase and ribonuclease Ⅱ. Mutations which substantially reduced the activity of these 3'-exonucleases caused a 10-fold increase in pulse- labeling of total poly(A) RNA in intact cells.