Protein kinases of retinal rod outer segments: identification and partial characterization of cyclic nucleotide dependent protein kinase and rhodopsin kinase

Biochemistry ◽  
1981 ◽  
Vol 20 (26) ◽  
pp. 7532-7538 ◽  
Author(s):  
Rehwa H. Lee ◽  
Bruce M. Brown ◽  
Richard N. Lolley
Keyword(s):  
Protein Kinase ◽  
Protein Kinases ◽  
Cyclic Nucleotide ◽  
Rod Outer Segments ◽  
Dependent Protein Kinase ◽  
Retinal Rod ◽  
Rhodopsin Kinase ◽  
Dependent Protein ◽  
Retinal Rod Outer Segments

scholarly journals Regulation by light of cyclic nucleotide-dependent protein kinases and their substrates in frog rod outer segments.

1990 ◽  
Vol 95 (3) ◽  
pp. 545-567 ◽  
Author(s):  
H Hamm
Keyword(s):  
Protein Kinase ◽  
Cyclic Nucleotide ◽  
Soluble Fraction ◽  
Subcellular Fractionation ◽  
Rod Outer Segments ◽  
Dependent Protein Kinase ◽  
Camp Dependent Protein Kinase ◽  
Outer Segments ◽  
Dependent Protein ◽  
Membrane Bound

Cyclic nucleotides (both cAMP and cGMP) stimulate the phosphorylation of several proteins of 65-70, 50-52, 21, 13, and 12 kD in rod outer segments (ROS) of the frog retina. Subcellular fractionation showed that phosphopeptides of 67, 21, 13, and 12 kD were soluble and phosphopeptides of 69, 67, 50-52, and 12 kD were membrane associated at physiological ionic strength. Components I and II, 13 and 12 kD, respectively, are the major cyclic nucleotide-dependent phosphoproteins of ROS and have been reported to be phosphorylated in the dark and dephosphorylated in the light. Under unstimulated conditions, phosphorylated Components I and II were found in the soluble fraction. Cyclic nucleotide stimulation of phosphorylation resulted in increased phospho-Components I and II in the soluble fraction, and phospho-Component II on the membrane. Light had no effect on the phosphorylation level of soluble Components I and II, but it caused a depletion within 1 s of the membrane-bound phospho-Component II. A half-maximal decrease in membrane-bound Component II was seen at 5 x 10(5) rhodopsins bleached per outer segment. The cyclic nucleotide-dependent protein kinase(s) were found primarily in the peripheral membrane fraction of ROS proteins. 8-bromo cyclic AMP was two orders of magnitude more effective than 8-bromo cyclic GMP at stimulating Component I and II phosphorylation. An active peptide of the Walsh inhibitor of cAMP-dependent protein kinase [PKI(5-22)amide] blocked the phosphorylation with an IC50 of 10 nM. Photoaffinity labeling studies with 8-N3-cAMP and 8-N3-cGMP revealed the presence of a 52-kD band specifically labeled with 8-N3-cAMP, but no specific 8-N3-cGMP labeling. These data suggest that cyclic nucleotide-dependent protein phosphorylation in ROS occurs via the activation of a cAMP-dependent protein kinase.

scholarly journals Immunofluorescent localization of cyclic nucleotide-dependent protein kinases on the mitotic apparatus of cultured cells.

1980 ◽  
Vol 87 (2) ◽  
pp. 336-345 ◽  
Author(s):  
C L Browne ◽  
A H Lockwood ◽  
J L Su ◽  
J A Beavo ◽  
A L Steiner
Keyword(s):  
Protein Kinase ◽  
Cyclic Amp ◽  
Protein Kinases ◽  
Cyclic Gmp ◽  
Cyclic Nucleotides ◽  
Mitotic Spindle ◽  
Cyclic Nucleotide ◽  
Dependent Protein Kinase ◽  
Mitotic Apparatus ◽  
Dependent Protein

Cyclic nucleotides and cyclic nucleotide-dependent protein kinases have been implicated in the regulation of cell motility and division, processes that depend on the cell cytoskeleton. To determine whether cyclic nucleotides or their kinases are physically associated with the cytoskeleton during cell division, fluorescently labeled antibodies directed against cyclic AMP, cyclic GMP, and the cyclic nucleotide-dpendent protein kinases were used to localize these molecules in mitotic PtK1 cells. Both the cyclic GMP-dependent protein kinase and the type II regulatory subunit of the cyclic AMP-dependent protein kinase were localized on the mitotic spindle. Throughout mitosis, their distribution closely resembled that of tubulin. Antibodies to cyclic AMP, cyclic GMP, and the type I regulatory and catalytic subunits of the cyclic AMP-dependent protein kinase did not label the mitotic apparatus. The association between specific components of the cyclic neucleotide system and the mitotic spindle suggests that cyclic nucleotide-dependent phosphorylation of spindle proteins, such as those of microtubules, may play a fundamental role in the regulation of spindle assembly and chromosome motion.

ANP stimulates phospholipase C in cultured RIMCT cells: roles of protein kinases and G protein

1991 ◽  
Vol 260 (4) ◽  
pp. F590-F595 ◽  
Author(s):  
T. Berl ◽  
J. Mansour ◽  
I. Teitelbaum
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Protein Kinases ◽  
G Protein ◽  
Pertussis Toxin ◽  
Cyclic Nucleotide ◽  
Dependent Protein Kinase ◽  
Kinase C ◽  
Dependent Protein ◽  
Stimulation Of

We examined the possibility that, in addition to stimulation of guanylate cyclase (GC), atrial natriuretic peptide (ANP) also activates phospholipase C (PLC) in cultured rat inner medullary collecting tubule (RIMCT) cells. ANP (10(-12)M) causes marked release of inositol trisphosphate (IP3) at a concentration that does not stimulate GC. Concentrations of ANP that stimulate GC (greater than or equal to 10(-10) M) result in attenuated IP3 release. Similarly, exogenous dibutyryl guanosine 3',5'-cyclic monophosphate (10(-6) M) markedly inhibits the response to 10(-10) M ANP. Inhibition of cyclic nucleotide-dependent protein kinase by H 8, but not inhibition of protein kinase C by H 7, restores the response to 10(-8) and 10(-6) M ANP. Therefore, activation of cyclic nucleotide-dependent protein kinase inhibits ANP-stimulated PLC activity. Activation of protein kinase C by phorbol 12-myristate-13-acetate (PMA) decreases ANP-stimulated IP3 production. Pretreatment with H 7, but not H 8, prevents inhibition by PMA. To explore a potential role for G proteins, we examined the effect of guanine nucleotide analogues on ANP-stimulated IP3 production in saponin-permeabilized cells. ANP-stimulated IP3 production is enhanced by GTP gamma S and is inhibited by GDP beta S. Similarly, preincubation with pertussis toxin prevents ANP-stimulated IP3 release. We conclude that ANP stimulates PLC in RIMCT cells via a pertussis toxin-sensitive G protein. Stimulation of PLC is inhibited on activation of either cyclic nucleotide or Ca2+-phospholipid dependent protein kinases.

Cross-activation: overriding cAMP/cGMP selectivities of protein kinases in tissues

1992 ◽  
Vol 70 (12) ◽  
pp. 1283-1289 ◽  
Author(s):  
Hang Jiang ◽  
John B. Shabb ◽  
Jackie D. Corbin
Keyword(s):  
Protein Kinase ◽  
Protein Kinases ◽  
Cyclic Nucleotide ◽  
The Other ◽  
Dependent Protein Kinase ◽  
Cgmp Dependent Protein Kinase ◽  
Camp Dependent Protein Kinase ◽  
Binding Domains ◽  
Dependent Protein ◽  
Camp And Cgmp

cAMP- and cGMP-dependent protein kinases are homologous proteins and are predicted to exhibit very similar three-dimensional structures. Their cyclic nucleotide binding domains share a high degree of amino acid sequence identity. cAMP- and cGMP-dependent protein kinases are activated relatively specifically by cAMP and cGMP, respectively; and a single alanine–threonine difference between cAMP- and cGMP-binding domains partially accounts for this specificity. Thus, it would be expected that cAMP and cGMP mediate separate physiological effects. However, owing in part to the lack of absolute specificity of either enzyme and to the relatively high level of cAMP or cGMP in certain tissues, it is also possible that either cyclic nucleotide could cross-activate the other kinase. Increases in either cAMP or cGMP cause pig coronary artery relaxation. However, only cGMP-dependent protein kinase specific cyclic nucleotide analogues are very effective in causing relaxation, and cAMP elevation in arteries treated with isoproterenol or forskolin activates cGMP-dependent protein kinase, in addition to cAMP-dependent protein kinase. Conversely, increases in either cAMP or cGMP cause Cl− secretion in T-84 colon carcinoma cells, and the cGMP level in T-84 cells can be elevated sufficiently by bacterial enterotoxin to activate cAMP-dependent protein kinase. These results imply specific regulation of cAMP- and cGMP-dependent protein kinases by the respective cyclic nucleotides, but either cyclic nucleotide is able to cross-activate the other kinase in certain tissues.Key words: cGMP, cAMP, smooth muscle relaxation, protein phosphorylation.

Effects of isoquinolonesulfonamides on action potential secretion coupling in pituitary cells

2010 ◽  
Vol 1 (1) ◽  
Author(s):  
Marko A. Popovic ◽  
Stanko S. Stojilkovic ◽  
Arturo E. Gonzalez-Iglesias
Keyword(s):  
Protein Kinase ◽  
Electrical Activity ◽  
Protein Kinases ◽  
Cyclic Nucleotide ◽  
Calcium Influx ◽  
Pituitary Cells ◽  
Prolactin Release ◽  
Dependent Protein Kinase ◽  
Voltage Gated ◽  
Dependent Protein

Abstract: Pituitary lactotrophs fire action potentials spontaneously and the associated voltage-gated calcium influx is sufficient to maintain high and steady prolactin release. Several intracellular proteins can mediate the action of calcium influx on prolactin secretion, including calmodulin-dependent protein kinases. Here, we studied effects of isoquinolonesulfonamides KN-62 and KN-93, calmodulin-dependent protein kinase inhibitors, and KN-92, an inactive analog, on spontaneous electrical activity, voltage-gated calcium influx, cyclic nucleotide production, and basal prolactin release.: The effects of these compounds on electrical activity and calcium signaling was measured in single lactotrophs and cyclic nucleotide production and prolactin release were determined in static culture and perifusion experiments of anterior pituitary cells from postpubertal female rats.: KN-62 and KN-93 blocked basal prolactin release in a dose- and time-dependent manner, suggesting that calmodulin-dependent protein kinase could mediate the coupling of electrical activity and secretion. However, a similar effect on basal prolactin release was observed on application of KN-92, which does not inhibit this kinase. KN-93 also inhibited cAMP and cGMP production, but inhibition of prolactin release was independent of the status of cyclic nucleotide production. Single cell measurements revealed abolition of spontaneous and depolarization-induced electrical activity and calcium transients in KN-92/93-treated cells, with a time course comparable to that observed in secretory studies.: The results suggest that caution should be used when interpreting data from studies using isoquinolonesulfonamides to evaluate the role of calmodulin-dependent protein kinases in excitable endocrine cells, because inactive compounds exhibit comparable effects on action potential secretion coupling to those of active compounds.

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