A5075572452- Receptor Mechanisms and Signaling
- Protein Kinase Regulation and GTPase Signaling
- Neuroscience and Neuropharmacology Research
- Photoreceptor and optogenetics research
- Neuropeptides and Animal Physiology
- Glycosylation and Glycoproteins Research
- Ion channel regulation and function
- Cellular transport and secretion
- Monoclonal and Polyclonal Antibodies Research
- Lipid Membrane Structure and Behavior
- Circadian rhythm and melatonin
- RNA Research and Splicing
- Enzyme Structure and Function
- Cellular Mechanics and Interactions
- Cell Adhesion Molecules Research
- Retinal Development and Disorders
- Advanced Fluorescence Microscopy Techniques
- Neurobiology and Insect Physiology Research
- Genomics and Chromatin Dynamics
- RNA and protein synthesis mechanisms
- Light effects on plants
- Microtubule and mitosis dynamics
- Drug Transport and Resistance Mechanisms
- Metabolism, Diabetes, and Cancer
- Chemical Synthesis and Analysis
Washington University in St. Louis
2012-2022
University of Missouri
2001
California Institute of Technology
1989-1991
National Institute of Diabetes and Digestive and Kidney Diseases
1991
National Health Research Institutes
1991
National Institutes of Health
1991
Rockefeller University
1991
Attachment of heterotrimeric G-proteins to the inner face plasma membrane is fundamental their role as signal transducers by allowing interaction with both receptors and effectors.Certain G-protein a subunits are anchored covalent myristoylation.
The interaction between receptor and a heterotrimeric G protein ( @ y ) is thought to involve the intracellular loops of receptors specific domains on protein.Here we show that chemically farnesylated peptide (PSfar) carboxyl-terminal domain (amino acids 60-71: DKNPFKELKGGC) subunit protein, G,, directly stabilizes active form rhodopsin, metarhodopsin 11 (M 11), also uncouples rhodopsin-G, interaction.Peptide activity significantly affected by absence isoprenoid moiety.Moreover, altering...
Signal-transducing guanine nucleotide-binding proteins (G proteins) are made up of three subunits, alpha, beta, and gamma. Each these subunits comprises a family proteins. The rules for association between members one with another to form multimer not known; it is clear whether associations specific or nonspecific. Other than transducin (Gt), the G protein in rod photoreceptors, most purified contain more subtype beta gamma subunits. Gt alpha subunit associated only 1 1. It known this...
Guanine nucleotide binding proteins (G proteins) that transduce signals from cell surface receptors to effector molecules are made up of three subunits, alpha, beta, and gamma. A complementary DNA clone encodes a 71-amino acid protein was isolated bovine brain; this contains peptide sequences were derived the purified gamma subunit Gi Go. The primary sequence G gamma) has 55 percent homology transducin (T also functional domains mammalian ras proteins. probe for isolating generated with use...
A large superfamily of transmembrane receptors control cellular responses to diverse extracellular signals by catalyzing activation specific types heterotrimeric GTP-binding proteins. How these recognize and promote nucleotide exchange on G protein α subunits initiate signal amplification is unknown. The three-dimensional structure the transducin (Gt) subunit C-terminal undecapeptide Gtα(340–350) IKENLKDCGLF was determined transferred nuclear Overhauser effect spectroscopy while it bound...
Guanine nucleotide-binding regulatory proteins (G proteins) are heterotrimeric that transduce extracellular signals into intracellular changes. Functionally different G have been identified by their alpha subunits. The beta and gamma subunits assumed to constitute a common pool shared among various protein heterotrimers. Two (gamma 3 4) through molecular cloning; these in addition two 1 2) were previously characterized. purified from variety of mammalian tissues examined with antisera...
Significance G-protein–coupled receptors control a variety of important cell behaviors. However, tools are not available to activate these in selected areas and exert over behavior. Here we recruit unique properties nonrhodopsin opsins all the major types G-protein signaling spatially confined regions single cells. We show that this approach can be used optically induce polarized behavior refashion early neuron differentiation. This optical applied other behaviors such as immune migration...
Sensory neurons use a pair of TRP channels to respond some itch-inducing chemicals.
Cells sense gradients of extracellular cues and generate polarized responses such as cell migration neurite initiation. There is static information on the intracellular signaling molecules involved in these responses, but how they dynamically orchestrate behaviors not well understood. A limitation has been lack methods to exert spatial temporal control over specific inside a living cell. Here we introduce optogenetic tools that act downstream native G protein–coupled receptor (GPCRs) provide...
Migratory immune cells use intracellular signaling networks to generate and orient spatially polarized responses extracellular cues. The monomeric G protein Cdc42 is believed play an important role in controlling the responses, but it has been difficult determine directly consequences of localized activation within cell. Here we used subcellular optogenetics how at one side a cell affects both behavior dynamic molecular throughout We found that sufficient directional migration. optically...
We investigated which subtypes of G-protein β subunits participate in voltage-dependent modulation N-type calcium channels. Calcium currents were recorded from cultured rat superior cervical ganglion neurons injected intranuclearly with DNA encoding five different subunits. Gβ 1 and 2 strongly mimicked the fast inhibition channels produced by many G-protein-coupled receptors. The 5 subunit much weaker effects than , whereas 3 4 nearly inactive these electrophysiological studies. specificity...
Post-translational prenylation of the carboxyl-terminal cysteine is a characteristic feature guanine nucleotide-binding protein (G protein) γ subunits. Recent findings show that farnesylated COOH-terminal tail γ1 subunit specific determinant rhodopsin-transducin coupling. We here when synthetic peptides to are chemically modified with geranyl, farnesyl, or geranylgeranyl groups and tested for their ability interact light activated rhodopsin, peptide significantly more effective. These...
Receptor-G protein interaction is characterized by cycles of association and dissociation. We present evidence which indicates that during receptor-G interaction, the C-terminal tail G gamma subunit, masked in beta complex, exposed establishes high-affinity contact with receptor. This potential conformational switch provides a mechanism to regulate coupling. may also be significant for role complex regulation effector function.
Fluorescence recovery after photobleaching of muscarinic receptors and G protein subunits tagged with cyan or yellow fluorescent showed that proteins were mobile not immobilized on the cell membrane. The protein-tagged Gα Gβ used to develop sensors coupled selectively M2 M3 receptors. In living Chinese hamster ovary cells, imaging emitted a fluorescence resonance energy transfer signal was abrogated receptor activation. When sequentially activated highly expressed endogenous at low levels,...
Interaction with a receptor is the first step in process of signal transduction by heterotrimeric (alpha beta gamma) G proteins. We have examined role protein gamma subunit interaction between (rhodopsin) and protein, transducin (Gt). obtained recombinant complexes containing same but three different types expressing them baculovirus/insect cell system. show that interact equally well alpha t) only specific to rod photoreceptors (gamma 1) able support t rhodopsin. This indicates direct for...
Heterotrimeric G proteins (alphabetagamma) mediate the majority of signaling pathways in mammalian cells. It is long held that protein function localized to plasma membrane. Here we examined spatiotemporal dynamics localization using fluorescence recovery after photobleaching, loss and a photoswitchable fluorescent protein, Dronpa. Unexpectedly, subunits shuttle rapidly (t1/2 < 1 min) between membrane intracellular membranes. We show consistent with such shuttling, constitutively reside...
The present model of G protein activation by protein-coupled receptors exclusively localizes their and function to the plasma membrane (PM). Observation spatiotemporal response subunits in a living cell receptor showed that 6 12 members gamma subunit family translocate specifically from PM endomembranes. as betagamma complexes, whereas alpha is retained on PM. Depending subunit, translocation occurs predominantly Golgi complex or endoplasmic reticulum. rate also varies with type. Different...