Browse
Submit Data
Databases
API
Help

Dataset Information

26 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Glucose and GLP-1 stimulate cAMP production via distinct adenylyl cyclases in INS-1E insulinoma cells.

ABSTRACT: In beta cells, both glucose and hormones, such as GLP-1, stimulate production of the second messenger cAMP, but glucose and GLP-1 elicit distinct cellular responses. We now show in INS-1E insulinoma cells that glucose and GLP-1 produce cAMP with distinct kinetics via different adenylyl cyclases. GLP-1 induces a rapid cAMP signal mediated by G protein-responsive transmembrane adenylyl cyclases (tmAC). In contrast, glucose elicits a delayed cAMP rise mediated by bicarbonate, calcium, and ATP-sensitive soluble adenylyl cyclase (sAC). This glucose-induced, sAC-dependent cAMP rise is dependent upon calcium influx and is responsible for the glucose-induced activation of the mitogen-activated protein kinase (ERK1/2) pathway. These results demonstrate that sAC-generated and tmAC-generated cAMP define distinct signaling cascades.

SUBMITTER: Ramos LS

PROVIDER: S-EPMC2518727 | biostudies-literature | 2008 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Glucose and GLP-1 stimulate cAMP production via distinct adenylyl cyclases in INS-1E insulinoma cells.

Ramos Lavoisier S LS Zippin Jonathan Hale JH Kamenetsky Margarita M Buck Jochen J Levin Lonny R LR

The Journal of general physiology 20080811 3

In beta cells, both glucose and hormones, such as GLP-1, stimulate production of the second messenger cAMP, but glucose and GLP-1 elicit distinct cellular responses. We now show in INS-1E insulinoma cells that glucose and GLP-1 produce cAMP with distinct kinetics via different adenylyl cyclases. GLP-1 induces a rapid cAMP signal mediated by G protein-responsive transmembrane adenylyl cyclases (tmAC). In contrast, glucose elicits a delayed cAMP rise mediated by bicarbonate, calcium, and ATP-sensi ...[more]

PMID: 18695009

Similar Datasets

Compartmentalized cAMP Generation by Engineered Photoactivated Adenylyl Cyclases.

Project description:Because small-molecule activators of adenylyl cyclases (AC) affect ACs cell-wide, it is challenging to explore the signaling consequences of AC activity emanating from specific intracellular compartments. We explored this issue using a series of engineered, optogenetic, spatially restricted, photoactivable adenylyl cyclases (PACs) positioned at the plasma membrane (PM), the outer mitochondrial membrane (OMM), and the nucleus (Nu). The biochemical consequences of brief photostimulation of PAC is primarily limited to the intracellular site occupied by the PAC. By contrast, sustained photostimulation results in distal cAMP signaling. Prolonged cAMP generation at the OMM profoundly stimulates nuclear protein kinase (PKA) activity. We have found that phosphodiesterases 3 (OMM and PM) and 4 (PM) modulate proximal (local) cAMP-triggered activity, whereas phosphodiesterase 4 regulates distal cAMP activity as well as the migration of PKA's catalytic subunit into the nucleus.

| S-EPMC6800631 | biostudies-literature

Glucose stimulation induces dynamic change of mitochondrial morphology to promote insulin secretion in the insulinoma cell line INS-1E.

Project description:Fission and fusion of mitochondrial tubules are the major processes regulating mitochondrial morphology. However, the physiological significance of mitochondrial shape change is poorly understood. Glucose-stimulated insulin secretion (GSIS) in pancreatic β-cells requires mitochondrial ATP production which evokes Ca(2+) influx through plasma membrane depolarization, triggering insulin vesicle exocytosis. Therefore, GSIS reflects mitochondrial function and can be used for evaluating functional changes associated with morphological alterations of mitochondria. Using the insulin-secreting cell line INS-1E, we found that glucose stimulation induced rapid mitochondrial shortening and recovery. Inhibition of mitochondrial fission through expression of the dominant-negative mutant DLP1-K38A eliminated this dynamic mitochondrial shape change and, importantly, blocked GSIS. We found that abolishing mitochondrial morphology change in glucose stimulation increased the mitochondrial inner membrane proton leak, and thus significantly diminished the mitochondrial ATP producing capacity in response to glucose stimulation. These results demonstrate that dynamic change of mitochondrial morphology is a previously unrecognized component for metabolism-secretion coupling of pancreatic β-cells by participating in efficient ATP production in response to elevated glucose levels.

| S-EPMC3614983 | biostudies-literature

Regulation and organization of adenylyl cyclases and cAMP.

Project description:Adenylyl cyclases are a critically important family of multiply regulated signalling molecules. Their susceptibility to many modes of regulation allows them to integrate the activities of a variety of signalling pathways. However, this property brings with it the problem of imparting specificity and discrimination. Recent studies are revealing the range of strategies utilized by the cyclases to solve this problem. Microdomains are a consequence of these solutions, in which cAMP dynamics may differ from the broad cytosol. Currently evolving methodologies are beginning to reveal cAMP fluctuations in these various compartments.

| S-EPMC1223734 | biostudies-other

Metabolic response of Insulinoma 1E cells to glucose stimulation studied by fluorescence lifetime imaging.

Project description:A cascade of highly regulated biochemical processes connects glucose stimulation to insulin secretion in specialized cells of mammalian pancreas, the ?-cells. Given the importance of this process for systemic glucose homeostasis, noninvasive and fast strategies capable to monitor the response to glucose in living cells are highly desirable. Here, we use the phasor-based approach to Fluorescence Lifetime IMaging (FLIM) microscopy to quantify the ratio between protein-bound and free Nicotinamide adenine dinucleotide (phosphate) species in their reduced form (NAD(P)H), and the Insulinoma cell line INS-1E as a ?-like cellular model. Phasor-FLIM analysis shows that the bound/free ratio of NAD(P)H species increases upon pulsed glucose stimulation. Such response is impaired by 48-hours preincubation of cells under hyperglycemic conditions. Phasor-FLIM concomitantly monitors the appearance of long-lifetime species (LLS) as characteristic products of hyperglycemia-induced oxidative stress.

| S-EPMC7354695 | biostudies-literature

Inhibitors of membranous adenylyl cyclases.

Project description:Membranous adenylyl cyclases (mACs) constitute a family of nine isoforms with different expression patterns. Studies with mAC gene knockout mice provide evidence for the notion that AC isoforms play distinct (patho)physiological roles. Consequently, there is substantial interest in the development of isoform-selective mAC inhibitors. Here, we review the current literature on mAC inhibitors. Structurally diverse inhibitors targeting the catalytic site and allosteric sites (e.g. the diterpene site) have been identified. The catalytic site of mACs accommodates both purine and pyrimidine nucleotides, with a hydrophobic pocket constituting a major affinity-conferring domain for substituents at the 2'- and 3'-O-ribosyl position of nucleotides. BODIPY-forskolin stimulates ACs 1 and 5 but inhibits AC2. However, so far, no inhibitor has been examined at all mAC isoforms, and data obtained with mAC inhibitors in intact cells have not always been interpreted cautiously enough. Future strategies for the development of the mAC inhibitor field are discussed critically.

| S-EPMC3273670 | biostudies-literature

Adenylyl cyclases and TRPV4 mediate Ca2+/cAMP dynamics to enhance fluid flow-induced osteogenesis in osteocytes.

Project description:Bone adapts to physical forces and this process is dependent on osteocyte mechanotransduction. One way osteocytes sense mechanical stimulation is through the primary cilium, a sensory organelle that triggers intracellular signaling cascades in response to fluid shear. Our lab previously determined that flow-induced ciliary Ca2+ influx and changes in cytosolic cAMP levels are critical for osteogenesis. We also identified two proteins important for osteocyte mechanotransduction: transient receptor potential vanilloid 4 (TRPV4) and adenylyl cyclase 6 (AC6). Interestingly, disrupting the Ca2+-binding ability of these proteins results in loss of function. Although knockdowns of TRPV4 and AC6 disrupt osteogenesis, there is no definitive evidence linking them to Ca2+/cAMP dynamics that facilitate osteocyte mechanotransduction. We therefore transfected MLO-Y4 osteocytes with AC3/6 and TRPV4 overexpression plasmids that fail to interact with Ca2+ and observed the response to fluid shear. Indeed, mutant groups exhibited adverse changes in cAMP and lower mRNA expression of an osteogenic marker, COX-2, at the onset of flow. This pattern persisted for AC3 and TRPV4 but we detected no difference in AC6 at longer exposure to flow. These results suggest TRPV4 and ACs mediate Ca2+/cAMP dynamics that are important for osteocyte mechanotransduction. These mechanisms are potential targets for therapeutics to combat bone loss and should be investigated further.

| S-EPMC6529196 | biostudies-literature

Cyanobacteriochrome-based photoswitchable adenylyl cyclases (cPACs) for broad spectrum light regulation of cAMP levels in cells.

Project description:Class III adenylyl cyclases generate the ubiquitous second messenger cAMP from ATP often in response to environmental or cellular cues. During evolution, soluble adenylyl cyclase catalytic domains have been repeatedly juxtaposed with signal-input domains to place cAMP synthesis under the control of a wide variety of these environmental and endogenous signals. Adenylyl cyclases with light-sensing domains have proliferated in photosynthetic species depending on light as an energy source, yet are also widespread in nonphotosynthetic species. Among such naturally occurring light sensors, several flavin-based photoactivated adenylyl cyclases (PACs) have been adopted as optogenetic tools to manipulate cellular processes with blue light. In this report, we report the discovery of a cyanobacteriochrome-based photoswitchable adenylyl cyclase (cPAC) from the cyanobacterium Microcoleus sp. PCC 7113. Unlike flavin-dependent PACs, which must thermally decay to be deactivated, cPAC exhibits a bistable photocycle whose adenylyl cyclase could be reversibly activated and inactivated by blue and green light, respectively. Through domain exchange experiments, we also document the ability to extend the wavelength-sensing specificity of cPAC into the near IR. In summary, our work has uncovered a cyanobacteriochrome-based adenylyl cyclase that holds great potential for the design of bistable photoswitchable adenylyl cyclases to fine-tune cAMP-regulated processes in cells, tissues, and whole organisms with light across the visible spectrum and into the near IR.

| S-EPMC5986202 | biostudies-literature

Rhodopsin-cyclases for photocontrol of cGMP/cAMP and 2.3 A structure of the adenylyl cyclase domain.

Project description:The cyclic nucleotides cAMP and cGMP are important second messengers that orchestrate fundamental cellular responses. Here, we present the characterization of the rhodopsin-guanylyl cyclase from Catenaria anguillulae (CaRhGC), which produces cGMP in response to green light with a light to dark activity ratio >1000. After light excitation the putative signaling state forms with τ = 31 ms and decays with τ = 570 ms. Mutations (up to 6) within the nucleotide binding site generate rhodopsin-adenylyl cyclases (CaRhACs) of which the double mutated YFP-CaRhAC (E497K/C566D) is the most suitable for rapid cAMP production in neurons. Furthermore, the crystal structure of the ligand-bound AC domain (2.25 Å) reveals detailed information about the nucleotide binding mode within this recently discovered class of enzyme rhodopsin. Both YFP-CaRhGC and YFP-CaRhAC are favorable optogenetic tools for non-invasive, cell-selective, and spatio-temporally precise modulation of cAMP/cGMP with light.

| S-EPMC5967339 | biostudies-literature

Distinct mechanisms of calmodulin binding and regulation of adenylyl cyclases 1 and 8.

Project description:Calmodulin (CaM), by mediating the stimulation of the activity of two adenylyl cyclases (ACs), plays a key role in integrating the cAMP and Ca(2+) signaling systems. These ACs, AC1 and AC8, by decoding discrete Ca(2+) signals can contribute to fine-tuning intracellular cAMP dynamics, particularly in neurons where they predominate. CaM comprises an α-helical linker separating two globular regions at the N-terminus and the C-terminus that each bind two Ca(2+) ions. These two lobes have differing affinities for Ca(2+), and they can interact with target proteins independently. This study explores previous indications that the two lobes of CaM can regulate AC1 and AC8 differently and thereby yield different responses to cellular transitions in [Ca(2+)](i). We first compared by glutathione S-transferase pull-down assays and offline nanoelectrospray ionization mass spectrometry the interaction of CaM and Ca(2+)-binding deficient mutants of CaM with the internal CaM binding domain (CaMBD) of AC1 and the two terminal CaMBDs of AC8. We then examined the influence of these three CaMBDs on Ca(2+) binding by native and mutated CaM in stopped-flow experiments to quantify their interactions. The three CaMBDs show quite distinct interactions with the two lobes of CaM. These findings establish the critical kinetic differences between the mechanisms of Ca(2+)-CaM activation of AC1 and AC8, which may underpin their different physiological roles.

| S-EPMC3466776 | biostudies-literature

Pro-inflammatory cytokines attenuate glucose-stimulated insulin secretion from INS-1E insulinoma cells by restricting mitochondrial pyruvate oxidation capacity - Novel mechanistic insight from real-time analysis of oxidative phosphorylation.

Project description:Pro-inflammatory cytokines cause pancreatic beta cell failure during the development of type 2 diabetes. This beta cell failure associates with mitochondrial dysfunction, but the precise effects of cytokines on mitochondrial respiration remain unclear. To test the hypothesis that pro-inflammatory cytokines impair glucose-stimulated insulin secretion (GSIS) by inhibiting oxidative ATP synthesis, we probed insulin release and real-time mitochondrial respiration in rat INS-1E insulinoma cells that were exposed to a combination of 2 ng/mL interleukin-1-beta and 50 ng/mL interferon-gamma. We show that 24-h exposure to these cytokines dampens both glucose- and pyruvate-stimulated insulin secretion (P < 0.0001 and P < 0.05, respectively), but does not affect KCl-induced insulin release. Mirroring secretory defects, glucose- and pyruvate-stimulated mitochondrial respiration are lowered after cytokine exposure (P < 0.01). Further analysis confirms that cytokine-induced mitochondrial respiratory defects occur irrespective of whether fuel oxidation is coupled to, or uncoupled from, ATP synthesis. These observations demonstrate that pro-inflammatory cytokines attenuate GSIS by restricting mitochondrial pyruvate oxidation capacity. Interleukin-1-beta and interferon-gamma also increase mitochondrial superoxide levels (P < 0.05), which may reinforce the inhibition of pyruvate oxidation, and cause a modest (20%) but significant (P < 0.01) loss of INS-1E cells. Cytokine-induced INS-1E cell failure is insensitive to palmitoleate and linoleate, which is at odds with the cytoprotection offered by unsaturated fatty acids against harm caused by nutrient excess. Our data disclose a mitochondrial mechanism for cytokine-impaired GSIS in INS-1E cells, and suggest that inflammatory and nutrient-related beta cell failure emerge, at least partly, through distinct paths.

| S-EPMC6023166 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data