The Androgenic Regulation of Abundant mRNA in Rat Ventral Prostate.

The most abundant poly(A)-containing RNA accounting for approximately half the total is regulated by testosterone in rat ventral prostate. A complementary DNA probe to these sequences was isolated by hybridizing the total cellular poly(A)-containing RNA with its complementary DNA to an r_ot_½ value of 2 × 10^-2 mol 1^-1 s and separating the abundant cDNA from the non-abundant cDNA by hydroxyapatite chromatography. The abundant cDNA, complementary to about three different poly(A)-containing RNA sequences comprising 45% of the total poly(A)-containing RNA, has been used to investigate the effect of androgens on their metabolism. Following castration there is a progressive decrease in the abundant sequences from 450% of the total in normal animals to less than 0.03% after 14 days; testosterone administration in vivo results in their regeneration. The sequences were not detected in seminal vesicle, liver, heart or spleen but represented about 0.01% of the poly(A)-containing RNA of kidney. Translation of the poly(A)-containing RNA in vitro in a cell-free system derived from wheat germ resulted in the synthesis of four major proteins which could be separated by polyacrylamide gel electrophoresis. Their synthesis, as measured by [³⁵S]methionine incorporation, accounted for 40–50% of the total incorporation and declined after castration but was restored by testosterone treatment. We conclude that a class of abundant poly(A)-containing RNA which codes for four major proteins is regulated by testosterone in rat ventral prostate. [ABSTRACT FROM AUTHOR]