The role of regucalcin, which is a regulatory protein of @entity460 signaling, in the regulation of protein phosphatase activity in the nuclei of @entity35 kidney cortex was investigated. Protein phosphatase activity towards @entity10393 , @entity8283 , and @entity8284 was found in the nuclei. The enzyme activity towards three @entity13269 was significantly increased by the addition of @entity12374 (10-50 microM) in the enzyme reaction mixture. This increase was significantly inhibited by @entity6105 (25 or 50 microM), an antagonist of calmodulin. The presence of regucalcin (50 or 100 nM) in the enzyme reaction mixture caused a significant decrease in protein phosphatase activity towards three @entity13269 . This effect was also seen in the presence of @entity460 (25 microM) and/or calmodulin (5 microg/ml). Protein phosphatase activity towards three @entity13269 was significantly increased in the presence of anti-regucalcin monoclonal antibody (25 or 50 ng/ml) in the enzyme reaction mixture. This effect was completely blocked by the addition of regucalcin (100 nM). The effect of antibody (25 ng/ml) in increasing protein phosphatase activity towards @entity10393 was significantly inhibited by @entity8870 (10(-4) M). Also, the antibody's effect towards @entity8283 and @entity8284 was significantly inhibited by @entity205 (10(-5) M). Endogenous regucalcin was found in the nuclei of @entity35 kidney cortex using Western blot analysis. Nuclear regucalcin level was significantly reduced by the administration of saline (0.9% @entity1219 ) for seven days in @entity35 . Protein phosphatase activity towards three @entity13269 was significantly decreased by saline administration. The effect of anti-regucalcin monoclonal antibody (25 ng/ml) in increasing protein phosphatase activity towards three @entity13269 was weakened in the renal cortex nuclei of saline-administrated @entity35 . The present study demonstrates that endogenous regucalcin plays a suppressive role in the regulation of protein phosphatase activity in the nuclei of @entity35 kidney cortex cells.

Inhibitory effect of regucalcin on protein phosphatase activity in the nuclei of XXXX kidney cortex.

@entity8283 :: ('CHEBI:15811', 'Chemical') :: ['phosphoserine'] @entity1219 :: ('CHEBI:26710', 'Chemical') :: ['NaCl'] @entity10393 :: ('CHEBI:74956', 'Chemical') :: ['phosphotyrosine'] @entity6105 :: ('MESH:D014268', 'Chemical') :: ['trifluoperazine'] @entity13269 :: ('CHEBI:26051', 'Chemical') :: ['phosphoamino acids'] @entity205 :: ('MESH:D016572', 'Chemical') :: ['cyclosporin A'] @entity460 :: ('MESH:D002118', 'Chemical') :: ['calcium'] @entity35 :: ('10116', 'Species') :: ['rat', 'rats'] @entity12374 :: ('MESH:D002122', 'Chemical') :: ['calcium chloride'] @entity8284 :: ('CHEBI:37525', 'Chemical') :: ['phosphothreonine'] @entity8870 :: ('MESH:D014638', 'Chemical') :: ['vanadate']
@entity35 :: (10116,Species) :: ['rat']
