Differential regulation of phosphoinositide and phosphatidylcholine hydrolysis by protein kinase C-beta 1 overexpression. Effects on stimulation by alpha-thrombin, guanosine 5'-O-(thiotriphosphate), and calcium.

Pachter, Jonathan A.; Pai, Jin-Keon; Mayer-Ezell, Rosemary; Petrin, Joanne; Dobek, E.; Bishop, W. Robert

doi:10.1016/s0021-9258(19)50168-5

Cited by 70 publications

(1 citation statement)

References 62 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is very interesting, since phosphatidic acid acts as a second messenger, which is generated when phospholipase D is activated and might be another signal for the activation of PKC. In this way, PKC isoforms, especially α and βI, have shown to be dowstream targets of PLD ( − ). More recently, PKCα has been implicated in this pathway in vivo, and such studies have confirmed that phosphatidic acid activates PKCα, in bovine brain cytosol, leading to a Ser/Thr phosphorylation cascade ().…”

Section: Discussionmentioning

confidence: 99%

Effect of Calcium and Phosphatidic Acid Binding on the C2 Domain of PKCα As Studied by Fourier Transform Infrared Spectroscopy

1999

View full text Add to dashboard Cite

Fourier transform infrared (FTIR) spectroscopy was used to investigate the structural and thermal denaturation of the C2 domain of PKC alpha (PKC-C2) and its complexes with Ca(2+) and phosphatidic acid vesicles. The amide I regions in the original spectra of PKC-C2 in the Ca(2+)-free and Ca(2+)-bound states are both consistent with a predominantly beta-sheet secondary structure below the denaturation temperatures. Spectroscopic studies of the thermal denaturation revealed that for the PKC-C2 domain alone the secondary structure abruptly changed at 50 degrees C. While in the presence of 2 and 12.5 mM Ca(2+), the thermal stability of the protein increased to 60 and 70 degrees C, respectively. Further studies using a mutant lacking two important amino acids involved in Ca(2+) binding (PKC-C2D246/248N) demonstrated that these mutations were inherently more stable to thermal denaturation than the wild-type protein. Phosphatidic acid binding to the PKC-C2 domain was characterized, and the lipid-protein binding became Ca(2+)-independent when 100 mol% phosphatidic acid vesicles were used. The mutant lacking two Ca(2+) binding sites was also able to bind to phosphatidic acid vesicles. The effect of lipid binding on secondary structure and thermal stability was also studied. Beta-sheet was the predominant structure observed in the lipid-bound state, although the percentage represented by this structure in the total area of the amide I band significantly decreased from 60% in the lipid-free state to 47% in the lipid-bound state. This decrease in the beta-sheet component of the lipid-bound complex correlates well with the significant increase observed in the 1644 cm(-1) band which can be assigned to loops and disordered structure. Thermal stability after lipid binding was very high, and no sign of thermal denaturation was observed in the presence of lipids under the conditions that were studied.

show abstract

Section: Discussionmentioning

confidence: 99%

Effect of Calcium and Phosphatidic Acid Binding on the C2 Domain of PKCα As Studied by Fourier Transform Infrared Spectroscopy

1999

View full text Add to dashboard Cite

show abstract

Protein kinase C β modulates thrombin-induced Ca2+ signaling and endothelial permeability increase

et al. 1998

View full text Add to dashboard Cite

We investigated the function of the Ca2+-dependent protein kinase C (PKC) beta1 in the regulation of endothelial barrier property. Human dermal microvascular endothelial cells (HMEC-1) were transduced with full-length PKCbeta1 antisense (AS) cDNA or control pLNCX vector to generate stable cell lines (HMEC-AS and HMEC-pLNCX, respectively). Analyses indicated that HMEC-AS expressed the antisense PKCbeta1 transcript with decreased PKCbeta protein level (without a change in PKCalpha or PKCepsilon). The baseline transendothelial 125I-albumin clearance rates of HMEC-1, HMEC-pLNCX, and HMEC-AS were 5.0+/-0.5 x 10(-2), 6.8+/-0.4 x 10(-2), and 6.9+/-0.6 x 10(-2) microl/min, respectively. Activation of HMEC-1 and HMEC-pLNCX with phorbol 12-myristate 13-acetate (PMA) increased the rates to the respective 14.5+/-1.7 x 10(-2) microl/min and 16.9+/-2.8 x 10(-2) microl/min (corresponding to 191% and 149% increases over baseline). However, in HMEC-AS, PMA increased the rate to 9.8+/-1.0 x 10(-2) microl/min (42%). When HMEC-1 and HMEC-pLNCX were activated with thrombin, the rates increased to 10.8+/-1.4 x 10(-2) and 14.0+/-1.9 x 10(-2) microl/min, respectively (116% and 106%). In contrast, thrombin stimulation of HMEC-AS more than doubled the increase to 27.2+/-3.5 x 10(-2) microl/min (294%). Furthermore, the thrombin-induced peak increase in the [Ca2+]i in HMEC-AS was greater than in control cells. Fluorescence-activated cell sorter analysis of thrombin receptor expression indicated that the augmented thrombin-induced responses were not attributable to altered receptor density in HMEC-AS. These results indicate that PKCbeta functions in a negative feedback manner to inactivate thrombin-generated signals and thereby modulates the endothelial permeability increase. Because decreased PKCbeta expression significantly reduced the PMA-induced permeability increase, PKCbeta may downregulate thrombin receptor function upstream of PKC activation (i.e., Ca2+).

show abstract

Phospholipid‐Derived Second Messengers

Exton

1998

Comprehensive Physiology

View full text Add to dashboard Cite

The sections in this article are: Inositol Phospholipid Hydrolysis Functional Significance Phosphoinositide Phospholipases as Targets of Hormones and Growth Factors Phosphatidylinositol 3,4,5‐Trisphosphate Synthesis Phosphatidylinositol 3‐Kinases as Targets of Hormones and Growth Factors Role of Phosphatidylinositol 3‐Kinase in Cell Function Phosphatidylcholine Hydrolysis Phosphatidylcholine Hydrolysis by Phospholipase D and Its Functional Significance Phospholipase D as a Target of Hormones and Growth Factors Agonist‐Stimulated Phosphatidylcholine Hydrolysis by Phospholipase C Agonist‐Stimulated Phosphatidylcholine Hydrolysis by Phospholipase A 2 Sphingomyelin Hydrolysis and Its Functional Significance Summary

show abstract

Differential regulation of phosphoinositide and phosphatidylcholine hydrolysis by protein kinase C-beta 1 overexpression. Effects on stimulation by alpha-thrombin, guanosine 5'-O-(thiotriphosphate), and calcium.

Cited by 70 publications

References 62 publications

Effect of Calcium and Phosphatidic Acid Binding on the C2 Domain of PKCα As Studied by Fourier Transform Infrared Spectroscopy

Effect of Calcium and Phosphatidic Acid Binding on the C2 Domain of PKCα As Studied by Fourier Transform Infrared Spectroscopy

Protein kinase C β modulates thrombin-induced Ca2+ signaling and endothelial permeability increase

Phospholipid‐Derived Second Messengers

Contact Info

Product

Resources

About