Association of casein kinase 2 with nuclear chromatin in relation to androgenic regulation of rat prostate.
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 5 alpha-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.
Ahmed
K
K
Cellular and Molecular Biochemistry Research Laboratory, University of Minnesota, Minneapolis.
Yenice
S
S
Davis
A
A
Goueli
S A
SA
D000595:Amino Acid Sequence; D000728:Androgens / Q000502:physiology*; D000818:Animals; D015153:Blotting, Western; D047388:Casein Kinases; D002467:Cell Nucleus / Q000201:enzymology*; D002843:Chromatin / Q000201:enzymology*; D013196:Dihydrotestosterone / Q000494:pharmacology; D008297:Male; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000737:chemistry; D009919:Orchiectomy; D011467:Prostate / Q000187:drug effects / Q000201:enzymology*; D011494:Protein Kinases / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley
D000728:Androgens; D002843:Chromatin; D009842:Oligopeptides; D013196:Dihydrotestosterone; D011494:Protein Kinases; D047388:Casein Kinases