ADP-ribosyl cyclase coupled with receptors via G proteins.
Crude cell membranes in mammalian cells contain ADP-ribosyl cyclase, which converts NAD+ to cyclic ADP-ribose. Acetylcholine either increases or inhibits this activity in NG108-15 neuronal cells and adrenal chromaffin cells in a muscarinic receptor subtype-specific manner. Activation or inhibition of the cyclase activity is mimicked by GTP and blocked by bacterial toxins. These findings suggest that hormone or neurotransmitter receptors utilize the direct signaling pathway to ADP-ribosyl cyclase via G proteins within cell membranes, analogous to the previously established transduction pathways to adenylyl cyclase and phospholipase Cbeta.
Higashida
H
H
Department of Biophysics, NIRI, Kanazawa University School of Medicine, Japan. Haruhiro@med.kanazawa-u.ac.jp
D036541:ADP-ribosyl Cyclase; D051997:ADP-ribosyl Cyclase 1; D000818:Animals; D015703:Antigens, CD; D000943:Antigens, Differentiation / Q000378:metabolism*; D002460:Cell Line; D019204:GTP-Binding Proteins / Q000378:metabolism*; D006160:Guanosine Triphosphate / Q000378:metabolism; D009243:NAD / Q000378:metabolism; D009244:NAD+ Nucleosidase / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000378:metabolism*; D015398:Signal Transduction
D015703:Antigens, CD; D000943:Antigens, Differentiation; D011956:Receptors, Cell Surface; D009243:NAD; D006160:Guanosine Triphosphate; D036541:ADP-ribosyl Cyclase; D009244:NAD+ Nucleosidase; D051997:ADP-ribosyl Cyclase 1; D019204:GTP-Binding Proteins