Ras-dependent activation of fibroblast mitogen-activated protein kinase by 5-HT1A receptor via a G protein beta gamma-subunit-initiated pathway.
Serotonin (5-HT) is a potent mitogen in many cells types, an action which is frequently mediated through pertussis toxin-sensitive G proteins. In the current study, we used pharmacological inhibitors and dominant negative signaling constructs to delineate elements which participate in the activation of MAPK, a growth-associated mitogen-activated protein kinase, by human G protein-coupled 5-HT1A receptor transfected into CHO-K1 cells in a stable manner. The activation pathway does not directly involve phorbol ester-sensitive protein kinase C types, but does require (i) pertussis toxin-sensitive G protein beta gamma-subunits, (ii) a staurosporine- and genistein-sensitive protein kinase, (iii) phosphoinositide-3'-kinase activity, (iv) activation of Sos in a multimolecular complex that contains p46Shc, and p52Shc, and Grb2, (v) the GTPase p21Ras, and (vi) the protein kinase p74Raf-1. These data demonstrate that the 5-HT1A receptor mediates MAPK activity by convergence upon a common activation pathway that is shared with receptor tyrosine kinases.
Department of Medicine (Nephrology and Cardiology), Duke University Medical Center, Durham, North Carolina, USA.
M N
MN
Garnovskaya
T
T
van Biesen
B
B
Hawe
S
S
Casañas Ramos
R J
RJ
Lefkowitz
J R
JR
Raymond
D048868:Adaptor Proteins, Signal Transducing; D033942:Adaptor Proteins, Vesicular Transport; D000818:Animals; D016466:CHO Cells; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000276:immunology / Q000378:metabolism*; D006224:Cricetinae; D004789:Enzyme Activation / Q000187:drug effects; D051380:GRB2 Adaptor Protein; D019204:GTP-Binding Proteins / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000235:genetics; D015151:Immunoblotting; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D037342:Pertussis Toxin; D011233:Precipitin Tests; D011505:Protein-Tyrosine Kinases / Q000276:immunology / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D020794:Receptor Protein-Tyrosine Kinases / Q000378:metabolism; D011985:Receptors, Serotonin / Q000235:genetics / Q000378:metabolism*; D044263:Receptors, Serotonin, 5-HT1; D055765:Shc Signaling Adaptor Proteins; D015398:Signal Transduction / Q000502:physiology; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1; D014162:Transfection / Q000235:genetics; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
D048868:Adaptor Proteins, Signal Transducing; D033942:Adaptor Proteins, Vesicular Transport; D051380:GRB2 Adaptor Protein; D011506:Proteins; D011985:Receptors, Serotonin; D044263:Receptors, Serotonin, 5-HT1; C528024:SHC1 protein, human; D055765:Shc Signaling Adaptor Proteins; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1; D010566:Virulence Factors, Bordetella; D037342:Pertussis Toxin; D011505:Protein-Tyrosine Kinases; D020794:Receptor Protein-Tyrosine Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D019204:GTP-Binding Proteins