The nuclear matrix of the prostate contains acceptor sites for androgen receptors

In cell-free binding experiments, androgen receptors of rat ventral prostate cytosol bound with high affinity (Kd = 10(-10) M) to a saturable number of sites (acceptors) associated with the nuclear matrix of the prostate. This binding was dependent on the presence of an activated androgen-receptor complex. In addition, the binding was tissue-specific, since liver nuclear matrix, in contrast, contained only 15-20% as many acceptors for androgen receptors as the prostate nuclear matrix. The prostate nuclear matrix contained approximately 75% of the number of total nuclear acceptor sites. Matrix-associated acceptor sites appear to be associated with the internal RNA-protein network of the nuclear matrix since the peripheral lamina component of the matrix bound only 30% as many receptors as the intact nuclear matrix.