title: Physiological regulation of G protein-linked signaling.
abstract: Heterotrimeric G proteins in vertebrates constitute a family molecular switches that transduce the activation of a populous group of cell-surface receptors to a group of diverse effector units. The receptors include the photopigments such as rhodopsin and prominent families such as the adrenergic, muscarinic acetylcholine, and chemokine receptors involved in regulating a broad spectrum of responses in humans. Signals from receptors are sensed by heterotrimeric G proteins and transduced to effectors such as adenylyl cyclases, phospholipases, and various ion channels. Physiological regulation of G protein-linked receptors allows for integration of signals that directly or indirectly effect the signaling from receptor-->G protein-->effector(s). Steroid hormones can regulate signaling via transcriptional control of the activities of the genes encoding members of G protein-linked pathways. Posttranscriptional mechanisms are under physiological control, altering the stability of preexisting mRNA and affording an additional level for regulation. Protein phosphorylation, protein prenylation, and proteolysis constitute major posttranslational mechanisms employed in the physiological regulation of G protein-linked signaling. Drawing upon mechanisms at all three levels, physiological regulation permits integration of demands placed on G protein-linked signaling.
authors.affiliation: Department of Molecular Pharmacology, Diabetes and Metabolic Diseases Research Center, University Medical Center, State University of New York/Stony Brook, Stony Brook, New York 11794-8651, USA.
authors.forename: A J
authors.initials: AJ
authors.lastname: Morris
authors.forename: C C
authors.initials: CC
authors.lastname: Malbon
mesh_terms: D000818:Animals; D004194:Disease; D019204:GTP-Binding Proteins / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental; D020962:Heterotrimeric GTP-Binding Proteins / Q000502:physiology; D006801:Humans; D011499:Protein Processing, Post-Translational; D011956:Receptors, Cell Surface / Q000235:genetics / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology*; D014158:Transcription, Genetic
chemical_list: D011956:Receptors, Cell Surface; D019204:GTP-Binding Proteins; D020962:Heterotrimeric GTP-Binding Proteins