Abstract
Casein kinase 2 (CK-2) is a ubiquitous messenger-independent protein serine/threonine kinase that has been implicated in growth control. We have studied the activity and subcellular location of CK-2 in adult rat ventral prostate in relation to androgen withdrawal and administration. Androgen deprivation by castration results in a faster decline in CK-2 activity associated with prostatic nuclei than that in the cytosol. Nuclear CK-2 associated with chromatin is reduced at an even greater rate than that in the total nucleus. Reversal of these events by administration of a single dose of 5α-dihydrotestosterone to adult rats castrated 144 hr previously was accompanied by a differential early enhancement of chromatin-associated CK-2 activity, with a concomitant decrease in the CK-2 activity present in the cytosol. Changes in the nuclear CK-2 activity correlated with the immunostainable enzyme protein in the nucleus. We propose that androgens evoke translocation of CK-2 from the cytoplasm to the nucleus (nucleoplasm) where its enhanced association with the chromatin constituents takes place. Conversely, withdrawal of circulating androgens due to castration evokes a dissociation of CK-2 from chromatin and eventual translocation of nucleoplasmic CK-2 to the cytoplasm. Modulations in the association of CK-2 with nuclear chromatin may represent an important mechanism of post-transcriptional regulation of nuclear CK-2 in relation to androgen action in the prostate.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 4426-4430 |
| Number of pages | 5 |
| Journal | Proceedings of the National Academy of Sciences of the United States of America |
| Volume | 90 |
| Issue number | 10 |
| State | Published - May 15 1993 |