TY - JOUR
T1 - Tyrosine phosphorylation-dependent stimulation of amyloid precursor protein secretion by the m3 muscarinic acetylcholine receptor
AU - Slack, Barbara E.
AU - Breu, Jeffrey
AU - Petryniak, Magdalena A.
AU - Srivastava, Kakul
AU - Wurtman, Richard J.
PY - 1995/4/7
Y1 - 1995/4/7
N2 - Stimulation of m1 and m3 muscarinic acetylcholine receptors, which are coupled to phosphoinositide hydrolysis and protein kinase C activation, has been shown to increase the release of soluble amyloid precursor protein derivatives (APPs). The effect is mimicked by phorbol esters, which directly activate protein kinase C. Using human embryonic kidney cells expressing individual muscarinic receptor subtypes, we found that stimulation of APPs release by the muscarinic agonist carbachol was only partially reduced by a specific inhibitor of protein kinase C (the bisindolylmaleimide GF 109203X), while the response to phorbol 12-myristate 13-acetate (PMA) was abolished. The increase in APPs release elicited by carbachol and PMA was accompanied by elevated tyrosine phosphorylation of several proteins and reduced by tyrosine kinase inhibitors; GF 109203X significantly reduced the stimulation of tyrosine phosphorylation by carbachol and PMA. Inhibition of protein tyrosine phosphatases by vanadyl hydroperoxide markedly increased cellular tyrosine phosphorylation and enhanced APPs release as effectively as PMA and carbachol. Direct phosphorylation of amyloid precursor protein on tyrosine residues following treatment with carbachol, PMA, or vanadyl hydroperoxide was not observed. The results implicate both tyrosine phosphorylation and protein kinase C-dependent mechanisms in the regulation of APPs release by G protein-coupled receptors, and suggest that carbachol and PMA increase APPs release from human embryonic kidney cells expressing m3 muscarinic receptors via partially divergent pathways that converge at a tyrosine phosphorylation- dependent step.
AB - Stimulation of m1 and m3 muscarinic acetylcholine receptors, which are coupled to phosphoinositide hydrolysis and protein kinase C activation, has been shown to increase the release of soluble amyloid precursor protein derivatives (APPs). The effect is mimicked by phorbol esters, which directly activate protein kinase C. Using human embryonic kidney cells expressing individual muscarinic receptor subtypes, we found that stimulation of APPs release by the muscarinic agonist carbachol was only partially reduced by a specific inhibitor of protein kinase C (the bisindolylmaleimide GF 109203X), while the response to phorbol 12-myristate 13-acetate (PMA) was abolished. The increase in APPs release elicited by carbachol and PMA was accompanied by elevated tyrosine phosphorylation of several proteins and reduced by tyrosine kinase inhibitors; GF 109203X significantly reduced the stimulation of tyrosine phosphorylation by carbachol and PMA. Inhibition of protein tyrosine phosphatases by vanadyl hydroperoxide markedly increased cellular tyrosine phosphorylation and enhanced APPs release as effectively as PMA and carbachol. Direct phosphorylation of amyloid precursor protein on tyrosine residues following treatment with carbachol, PMA, or vanadyl hydroperoxide was not observed. The results implicate both tyrosine phosphorylation and protein kinase C-dependent mechanisms in the regulation of APPs release by G protein-coupled receptors, and suggest that carbachol and PMA increase APPs release from human embryonic kidney cells expressing m3 muscarinic receptors via partially divergent pathways that converge at a tyrosine phosphorylation- dependent step.
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U2 - 10.1074/jbc.270.14.8337
DO - 10.1074/jbc.270.14.8337
M3 - Article
C2 - 7713942
AN - SCOPUS:0028935040
SN - 0021-9258
VL - 270
SP - 8337
EP - 8344
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 14
ER -