AJP - Regulatory, Integrative and Comparative Physiology, Vol 237, Issue 5 360-R365, Copyright © 1979 by American Physiological Society
Noncoordinate regulation of cytoplasmic RNA in compensatory renal hypertrophy
A. J. Ouellette and R. A. Malt
To examine the regulatory role of mRNA in compensatory renal hypertrophy,
the accumulation and decay of [3H]orotic acid in poly(A)-containing mRNA in
mouse kidney was analyzed after unilateral nephrectomy during the period of
maximal rRNA accretion. The distribution of radioactivity between newly
synthesized poly(A)-containing and poly(A)-lacing polysomal RNA was
altered, but no differences in mRNA half-life were observed in growth
compared with effects of sham nephrectomy. Radioactivity in polysomal
polyadenylated RNA was diminished by approximately 25% during growth where
mice were labeled after nephrectomy, but if mice were labeled 18 h before
operation, no difference was noted. Thus, accumulation of newly synthesized
poly(A)-containing mRNA relative to RNAs that lack poly(A) is changed early
in the course of renal hypertrophy. This noncoordinate regulation may
represent a control mechanism effective early in induced cell growth
involving mRNAs that lack poly(A).
