Protein kinases help regulate eukaryotic cell division. We investigated the regulation of @entity268 -dependent @entity12175 (PKA) and casein kinase (CK) type I activity in normal cells and in @entity5 . To assess this activity in biopsies we suggest a new parameter--the ratio of CK activity and total PKA activity divided by @entity268 concentration: CK/PKA/ @entity268 . In 98 samples of colon mucosa in normal, inflamed, polyp, and @entity420 cells, we found this parameter to be fairly constant in normal conditions and increased 10-fold in @entity694 ; the ratio does not depend on the place of biopsy or the @entity1 's age or sex. Experiments with model systems of concanavalin A-stimulated lymphocytes and regenerating @entity35 liver showed that in normal cell proliferation the parameter increases 2-3-fold, as compared to a 30-fold increase in @entity5 . Unlike normal cells, malignant cells show CK activation and decrease of @entity268 ; therefore, PKA activity decreases. This suggests a correlation of CK and PKA activity and significant damage to their regulation at pathological changes of tissue proliferation. To further study concerted CK and PKA regulation we used monoclonal antibodies (mAbs) against @entity268 -dependent @entity25180 regulatory subunit RKII beta. We produced 11 antibodies in three groups: inhibiting, which block @entity268 binding with RII beta and inhibit holoenzyme formation (RS6); activating, which enhance @entity268 binding and do not affect holoenzyme formation (RS28); and neutral (RS17). To investigate mAb influence on @entity25180 regulation in live cells we permeabilized @entity1911 PC12 by @entity11040 . When used at 5-microM concentration for 5 min, @entity11040 allowed us to deliver mAb into PC12 cells at 30-34-nM concentration, leaving 68-75% viable cells. @entity25180 activity was measured within 0.5 and 4 h after incorporation of mAbs into cells. After 30 min incorporation, mAb RS6 blocked PKA activation in PC12 cells under the influence of @entity268 ; other mAbs showed no effect. mAb RS6 caused a 4-fold increase of free C subunit activity 4 h after incorporation. mAb RS38 decreased R2C2 activity and did not influence C subunit activity. The change of free C subunit activity caused by mAb incorporation was followed by a synchronized, well-balanced change of CK type I activity, which suggests a correlation between the two phosphorylation systems of cell proteins.

XXXX : regulation and receptor-mediated delivery of antisense oligonucleotides and cytotoxic drugs.

@entity268 :: ('CHEBI:17489', 'Chemical') :: ['cAMP'] @entity1 :: ('9606', 'Species') :: ['patient'] @entity25180 :: ('64030(Tax:10116)', 'Gene') :: ['Protein kinase', 'protein kinase'] @entity11040 :: ('MESH:D004072', 'Chemical') :: ['digitonin'] @entity12175 :: ('25636(Tax:10116)', 'Gene') :: ['protein kinase A'] @entity1911 :: ('MESH:D010673', 'Disease') :: ['pheochromocytoma'] @entity5 :: ('MESH:D009369', 'Disease') :: ['cancer'] @entity35 :: ('10116', 'Species') :: ['rat'] @entity694 :: ('MESH:D003110', 'Disease') :: ['colon cancer'] @entity420 :: ('MESH:D000230', 'Disease') :: ['adenocarcinoma']
@entity12175 :: (25636(Tax:10116),Gene) :: ['Protein kinase A']
