Translation of messenger RNA from fetal and adult mouse kidney

Polyadenylated mRNA was prepared from fetal, adult, and regenerating adult mouse kidneys. The polyadenylated portion is 2% of total RNA in the fetus, falls abruptly to 1% after birth, and returns to about 2% in the adult. In vitro translation of these mRNA's showed great similarities between 17 and 20 day fetal samples and between the normal and regenerating adult samples, but few similarities between the fetal and adult samples. The data do not support the hypothesis that renal growth following contralateral nephrectomy may entail the de-repression of genes active in the fetus but not active in the normal adult.