scholarly journals The native structure of the activated Raf protein kinase is a membrane-bound multi-subunit complex.

1994 ◽  
Vol 269 (9) ◽  
pp. 6695-6701 ◽  
Author(s):  
M. Wartmann ◽  
R.J. Davis
Keyword(s):  
Protein Kinase ◽  
Native Structure ◽  
Membrane Bound

Spatial control of actin-based motility through plasmalemmal PtdIns(4,5)P2-rich raft assemblies.

2005 ◽  
Vol 72 ◽  
pp. 119-127 ◽  
Author(s):  
Tamara Golub ◽  
Caroni Pico
Keyword(s):  
Protein Kinase ◽  
Cell Surface ◽  
Actin Cytoskeleton ◽  
Lipid Rafts ◽  
Patch Clustering ◽  
Pkc Protein Kinase C ◽  
Membrane Bound ◽  
And Function ◽  
Cytoskeleton Dynamics ◽  
Syndrome Protein

The interactions of cells with their environment involve regulated actin-based motility at defined positions along the cell surface. Sphingolipid- and cholesterol-dependent microdomains (rafts) order proteins at biological membranes, and have been implicated in most signalling processes at the cell surface. Many membrane-bound components that regulate actin cytoskeleton dynamics and cell-surface motility associate with PtdIns(4,5)P2-rich lipid rafts. Although raft integrity is not required for substrate-directed cell spreading, or to initiate signalling for motility, it is a prerequisite for sustained and organized motility. Plasmalemmal rafts redistribute rapidly in response to signals, triggering motility. This process involves the removal of rafts from sites that are not interacting with the substrate, apparently through endocytosis, and a local accumulation at sites of integrin-mediated substrate interactions. PtdIns(4,5)P2-rich lipid rafts can assemble into patches in a process depending on PtdIns(4,5)P2, Cdc42 (cell-division control 42), N-WASP (neural Wiskott-Aldrich syndrome protein) and actin cytoskeleton dynamics. The raft patches are sites of signal-induced actin assembly, and their accumulation locally promotes sustained motility. The patches capture microtubules, which promote patch clustering through PKA (protein kinase A), to steer motility. Raft accumulation at the cell surface, and its coupling to motility are influenced greatly by the expression of intrinsic raft-associated components that associate with the cytosolic leaflet of lipid rafts. Among them, GAP43 (growth-associated protein 43)-like proteins interact with PtdIns(4,5)P2 in a Ca2+/calmodulin and PKC (protein kinase C)-regulated manner, and function as intrinsic determinants of motility and anatomical plasticity. Plasmalemmal PtdIns(4,5)P2-rich raft assemblies thus provide powerful organizational principles for tight spatial and temporal control of signalling in motility.

Classical conditioning increases membrane-bound protein kinase C in rabbit cerebellum

Neuroreport ◽  
1998 ◽  
Vol 9 (11) ◽  
pp. 2669-2673 ◽  
Author(s):  
John H. Freeman ◽  
Andrew M. Scharenberg ◽  
James L. Olds ◽  
Bernard G. Schreurs
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Classical Conditioning ◽  
Kinase C ◽  
Membrane Bound

scholarly journals Lipid-dependent Akt-ivity: where, when, and how

2019 ◽  
Vol 47 (3) ◽  
pp. 897-908 ◽  
Author(s):  
Katharina M. Siess ◽  
Thomas A. Leonard
Keyword(s):  
Plasma Membrane ◽  
Protein Kinase ◽  
Kinase Domain ◽  
Target Of Rapamycin ◽  
Endomembrane System ◽  
Essential Protein ◽  
Mechanistic Target Of Rapamycin ◽  
Subcellular Compartments ◽  
Membrane Bound ◽  
Phosphoinositide 3 Kinase

Abstract Akt is an essential protein kinase activated downstream of phosphoinositide 3-kinase and frequently hyperactivated in cancer. Canonically, Akt is activated by phosphoinositide-dependent kinase 1 and mechanistic target of rapamycin complex 2, which phosphorylate it on two regulatory residues in its kinase domain upon targeting of Akt to the plasma membrane by PI(3,4,5)P3. Recent evidence, however, has shown that, in addition to phosphorylation, Akt activity is allosterically coupled to the engagement of PI(3,4,5)P3 or PI(3,4)P2 in cellular membranes. Furthermore, the active membrane-bound conformation of Akt is protected from dephosphorylation, and Akt inactivation by phosphatases is rate-limited by its dissociation. Thus, Akt activity is restricted to membranes containing either PI(3,4,5)P3 or PI(3,4)P2. While PI(3,4,5)P3 has long been associated with signaling at the plasma membrane, PI(3,4)P2 is gaining increasing traction as a signaling lipid and has been implicated in controlling Akt activity throughout the endomembrane system. This has clear implications for the phosphorylation of both freely diffusible substrates and those localized to discrete subcellular compartments.

scholarly journals Membrane-Bound Protein Kinase A Inhibits Smooth Muscle Cell Proliferation In Vitro and In Vivo by Amplifying cAMP–Protein Kinase A Signals

2001 ◽  
Vol 88 (3) ◽  
pp. 319-324 ◽  
Author(s):  
Ciro Indolfi ◽  
Eugenio Stabile ◽  
Carmela Coppola ◽  
Adriana Gallo ◽  
Cinzia Perrino ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Smooth Muscle ◽  
Protein Kinase ◽  
Smooth Muscle Cell ◽  
Protein Kinase A ◽  
Membrane Bound ◽  
Proliferation In Vitro ◽  
Kinase A

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.

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