Cyclic AMP‐dependent phosphorylation of a 16 kDa protein in a plasma membrane‐enriched fraction of rat aortic myocytes

Boulanger-Saunier, Chantal; Kattenburg, David Michael; Stoclet, Jean‐Claude

doi:10.1016/0014-5793(85)80169-1

Cited by 15 publications

(4 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In intact skeletal muscle, addition of insulin can mimick tumour-promoting phorbol esters in increasing both protein kinase C activity (Walaas et al, 1987) and phospholemman phosphorylation (Walaas et al, 1991). Other studies have shown that phospholemman is phosphorylated following activation ofaor ,8-adrenergic receptors in myocardial sarcolemma and after activation of /)-adrenergic or vasopressin receptors in smooth muscle (Jones et al 1979(Jones et al , 1980(Jones et al , 1981Manalan and Jones, 1982;Boulanger-Saunier et al, 1985;Presti et al, 1985;Boulanger-Saunier and Stoclet, 1987).…”

Section: Introductionmentioning

confidence: 99%

Protein kinase C and cyclic AMP-dependent protein kinase phosphorylate phospholemman, an insulin and adrenaline-regulated membrane phosphoprotein, at specific sites in the carboxy terminal domain

Walaas

Czernik

Olstad

et al. 1994

Biochemical Journal

109

View full text Add to dashboard Cite

Phospholemman, a transmembrane, 72 residue protein enriched in striated muscle and heart [Palmer, Scott and Jones (1991) J. Biol. Chem. 266, 11126-11130], is phosphorylated in response to insulin [Walaas, Horn and Walaas (1991) Biochim. Biophys. Acta 1094, 92-102]. The present study is aimed at identifying the phosphorylation sites of this protein. A synthetic peptide, GTFRSS63IRRLS68TRRR (in the single letter code) and consisting of phospholemman residues 58-72, is a substrate for both protein kinase C and cyclic AMP (cAMP)-dependent protein kinase, with Km values of 6-7 microM for both enzymes. Amino acid sequencing of the phosphopeptide shows that protein kinase C phosphorylates both Ser-63 and Ser-68, while cAMP-dependent protein kinase phosphorylates Ser-68. Thermolytic phosphopeptide mapping of 32P-labelled phospholemman from rat diaphragms shows that treatment with insulin results in labelling of phosphopeptides containing both Ser-63 and Ser-68, whereas treatment with adrenaline results in labelling of the phosphopeptide containing Ser-68. Hence, insulin and adrenaline regulate the phosphorylation of phospholemman, presumably through protein kinase C and cAMP-dependent protein kinase, respectively, on partly overlapping phosphorylation sites.

show abstract

Section: Introductionmentioning

confidence: 99%

Protein kinase C and cyclic AMP-dependent protein kinase phosphorylate phospholemman, an insulin and adrenaline-regulated membrane phosphoprotein, at specific sites in the carboxy terminal domain

Walaas

Czernik

Olstad

et al. 1994

Biochemical Journal

109

View full text Add to dashboard Cite

show abstract

“…PLM is a plasma membrane protein found in cardiac (6,41,43), skeletal (55,56), and smooth muscle (10), liver (13), and adrenal tumor cells (57). Activation of ␣-or ␤-adrenergic receptors in the myocardial sarcolemma results in increased phosphorylation of PLM (23,32,43); activation of ␤-adrenergic or vasopressin receptors in smooth muscle also increases phosphorylation (9,10). In isolated guinea pig heart, administration of the ␤-adrenergic agonist, isoproterenol, results in phosphorylation of PLM, coinciding with an increase in contractility (42).…”

mentioning

confidence: 99%

Cytoplasmic targeting signals mediate delivery of phospholemman to the plasma membrane

Lansbery

Burcea

Mendenhall³

et al. 2006

American Journal of Physiology-Cell Physiology

View full text Add to dashboard Cite

show abstract

“…2). These data suggest that the 16/17-kDa phosphoprotein identified in smooth muscle plasma membrane preparations [12,13,14] was likely PLM. We found that the CP68 PLM signal correlated with cAMP-, but not cGMP-mediated relaxation (fig.…”

Section: Discussionmentioning

confidence: 86%

“…Three papers describe a 16- to 17-kDa phosphoprotein in smooth muscle that may well have been PLM (PLM has an apparent molecular weight of approximately 16 kDa on SDS gels) [1]. In 1985, Boulanger-Saunier et al [12] identified a 16-kDa phosphoprotein in a plasma membrane-enriched fraction of rat aortic smooth muscle cell membranes. This protein copurified with Na,K-ATPase and was phosphorylated by PKA in vitro and by isoproterenol in vivo.…”

Section: Introductionmentioning

confidence: 99%

Serine 68 Phospholemman Phosphorylation during Forskolin-Induced Swine Carotid Artery Relaxation

Rembold¹,

Ripley²,

Meeks³

et al. 2005

J Vasc Res

View full text Add to dashboard Cite

Background: Phospholemman (PLM) is an abundant phosphoprotein in the plasma membrane of cardiac, skeletal and smooth muscle. It is a member of the FXYD family of proteins that bind to and regulate the Na,K-ATPase. Protein kinase A (PKA) is known to phosphorylate PLM on serine 68 (S68), although the functional effect of S68 PLM phosphorylation is unclear. We therefore evaluated S68 PLM phosphorylation in swine carotid arteries. Methods: Two anti-PLM antibodies, one to S68 phosphorylated PLM and one to unphosphorylated PLM, were made to PLM peptides in rabbits and tested with purified PLM and PKA-treated PLM. Swine carotid arteries were mounted isometrically, contracted, relaxed with forskolin and then homogenized. Proteins were separated on SDS gels and the intensity of immunoreactivity to the two PLM antibodies determined on immunoblots. Results: The antipeptide antibody ‘C2’ primarily reacted with unphosphorylated PLM, and the antipeptide antibody ‘CP68’ detected S68 PLM phosphorylation. Histamine stimulation of intact swine carotid artery induced a contraction, increased the CP68 PLM antibody signal and reduced the C2 PLM antibody signal. High extracellular [K⁺] depolarization induced a contraction without altering the C2 or CP68 PLM signal. Forskolin-induced relaxation of histamine or extracellular [K⁺] contracted arteries correlated with an increased CP68 signal. Nitroglycerin-induced relaxation was not associated with changes in the C2 or CP68 PLM signal. Conclusions: These data suggest that a contractile agonist increased S68 PLM phosphorylation. Agents that increase [cAMP], but not agents that increase [cGMP], increased S68 PLM phosphorylation. S68 PLM phosphorylation may be involved in cAMP-dependent regulation of smooth muscle force.

show abstract

Cyclic AMP‐dependent phosphorylation of a 16 kDa protein in a plasma membrane‐enriched fraction of rat aortic myocytes

Cited by 15 publications

References 25 publications

Protein kinase C and cyclic AMP-dependent protein kinase phosphorylate phospholemman, an insulin and adrenaline-regulated membrane phosphoprotein, at specific sites in the carboxy terminal domain

Protein kinase C and cyclic AMP-dependent protein kinase phosphorylate phospholemman, an insulin and adrenaline-regulated membrane phosphoprotein, at specific sites in the carboxy terminal domain

Cytoplasmic targeting signals mediate delivery of phospholemman to the plasma membrane

Serine 68 Phospholemman Phosphorylation during Forskolin-Induced Swine Carotid Artery Relaxation

Contact Info

Product

Resources

About