Protein Kinase C Phosphorylates Nonmuscle Myosin-II Heavy Chain from Drosophila but Regulation of Myosin Function by This Enzyme Is Not Required for Viability in Flies†

Biochemistry ◽  
2001 ◽  
Vol 40 (12) ◽  
pp. 3606-3614 ◽  
Author(s):  
Zuowei Su ◽  
Daniel P. Kiehart
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Heavy Chain ◽  
Myosin Ii ◽  
Nonmuscle Myosin ◽  
Kinase C ◽  
Nonmuscle Myosin Ii

scholarly journals Metastasis-associated Mts1 (S100A4) Protein Modulates Protein Kinase C Phosphorylation of the Heavy Chain of Nonmuscle Myosin

1998 ◽  
Vol 273 (16) ◽  
pp. 9852-9856 ◽  
Author(s):  
Marina Kriajevska ◽  
Svetlana Tarabykina ◽  
Igor Bronstein ◽  
Norman Maitland ◽  
Mikhail Lomonosov ◽  
...  
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Heavy Chain ◽  
Nonmuscle Myosin ◽  
S100a4 Protein ◽  
Kinase C

scholarly journals Chemoattractant-mediated increases in cGMP induce changes in Dictyostelium myosin II heavy chain-specific protein kinase C activities.

1996 ◽  
Vol 134 (4) ◽  
pp. 911-921 ◽  
Author(s):  
A Dembinsky ◽  
H Rubin ◽  
S Ravid
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Heavy Chain ◽  
Myosin Ii ◽  
Specific Protein ◽  
Binding Activity ◽  
Cell Cortex ◽  
Kinase C ◽  
Camp Stimulation ◽  
Specific Protein Kinase

Myosin II heavy chain (MHC)-specific protein kinase C (MHC-PKC) isolated from the ameba, Dictyostelium discoideum, regulates myosin II assembly and localization in response to the chemoattractant cAMP (Abu-Elneel et al. 1996. J. Biol. Chem. 271:977- 984). Recent studies have indicated that cAMP-induced cGMP accumulation plays a role in the regulation of myosin II phosphorylation and localization (Liu, G., and P. Newell. 1991. J. Cell. Sci. 98: 483-490). This report describes the roles of cAMP and cGMP in the regulation of MHC-PKC membrane association, phosphorylation, and activity (hereafter termed MHC-PKC activities). cAMP stimulation of Dictyostelium cells resulted in translocation of MHC-PKC from the cytosol to the membrane fraction, as well as increasing in MHC-PKC phosphorylation and in its kinase activity. We present evidence that MHC is phosphorylated by MHC-PKC in the cell cortex which leads to myosin II dissociation from the cytoskeleton. Use of Dictyostelium mutants that exhibit aberrant cAMP-induced increases in cGMP accumulation revealed that MHC-PKC activities are regulated by cGMP. Dictyostelium streamer F mutant (stmF), which produces a prolonged peak of cGMP accumulation upon cAMP stimulation, exhibits prolonged increases in MHC-PKC activities. In contrast, Dictyostelium KI-10 mutant that lacks the normal cAMP-induced cGMP response, or KI-4 mutant that shows nearly normal cAMP-induced cGMP response but has aberrant cGMP binding activity, show no changes in MHC-PKC activities. We provide evidence that cGMP may affect MHC-PKC activities via the activation of cGMP-dependent protein kinase which, in turn, phosphorylates MHC-PKC. The results presented here indicate that cAMP-induced cGMP accumulation regulates myosin II phosphorylation and localization via the regulation of MHC-PKC.

HC fragment (C-terminal portion of the heavy chain) of tetanus toxin activates protein kinase C isoforms and phosphoproteins involved in signal transduction

2001 ◽  
Vol 356 (1) ◽  
pp. 97-103 ◽  
Author(s):  
Carles GIL ◽  
Imane CHAIB-OUKADOUR ◽  
Juan BLASI ◽  
José AGUILERA
Keyword(s):  
Signal Transduction ◽  
Protein Kinase C ◽  
Protein Kinase ◽  
Tyrosine Phosphorylation ◽  
Heavy Chain ◽  
Tetanus Toxin ◽  
Signal Transduction Pathways ◽  
Terminal Portion ◽  
Kinase C ◽  
Pkc Isoforms

A recent report [Gil, Chaib-Oukadour, Pelliccioni and Aguilera (2000) FEBS Lett. 481, 177–182] describes activation of signal transduction pathways by tetanus toxin (TeTx), a Zn2+-dependent endopeptidase synthesized by the Clostridium tetani bacillus, which is responsible for tetanus disease. In the present work, specific activation of protein kinase C (PKC) isoforms and of intracellular signal-transduction pathways, which include nerve-growth-factor (NGF) receptor trkA, phospholipase C(PLC)γ-1 and extracellular regulated kinases (ERKs) 1 and 2, by the recombinant C-terminal portion of the TeTx heavy chain (HC-TeTx) is reported. The activation of PKC isoforms was assessed through their translocation from the soluble (cytosolic) compartment to the membranous compartment, showing that clear translocation of PKC-α, −β, −γ and −δ isoforms exists, whereas PKC-∊ showed a slight decrease in its soluble fraction immunoreactivity. The PKC-∊ isoform showed no consistent response. Using immunoprecipitation assays against phosphotyrosine residues, time- and dose-dependent increases in tyrosine phosphorylation were observed in the trkA receptor, PLCγ-1 and ERK-1/2. The effects shown by the HC-TeTx fragment on tyrosine phosphorylation were compared with the effects produced by NGF. The trkA and ERK-1/2 activation were corroborated using phospho-specific antibodies against trkA phosphorylated on Tyr490, and antibodies against Thr/Tyr phosphorylated ERK-1/2. Moreover, PLCγ-1 phosphorylation was supported by its HC-TeTx-induced translocation to the membranous compartment, an event related to PLCγ-1 activation. Since HC-TeTx is the domain responsible for membrane binding and lacks catalytic activity, the activations described here must be exclusively triggered by the interaction of TeTx with a membrane component.

Sign in / Sign up

Export Citation Format

Share Document