Accumulation and decay of messenger ribonucleic acid in mouse kidney

The stability of polyadenylated messenger ribonucleic acid(mRNA) from cytoplasmic structures sedimenting faster than 40S was analyzed in normal mouse kidney. Incorporation of radioactivity into poly(A)-containing and poly(A)-lacking cytoplasmic RNAs separated by oligo(dT)-cellulose chromatography was determined after sedimentation of RNA IN SODIUM DODECYL SULFATE CONTAINING SUCROSE DENSITY GRADIENTS. Radioactivity accumulated in poly(A)-containing RNA during the first 6 h and then decayed exponentially. Beginning 8-12h after administering label, two components were evident in the decay curve of poly(A)-containing RNA; the short-lived component (approximately 57% of newly synthesized molecules) had an apparent half-life of 6h, and the second class (approximately 43% of new mRNA) was more stable, decaying with a 24-h half-life. These studies provide the basis for examining the regulation of mRNA stability during compensatory renal hypertrophy.