Activation of Store-Operated Ca2+ Current in Xenopus Oocytes Requires SNAP-25 but Not a Diffusible Messenger

Yao, Yong; Ferrer‐Montiel, Antonio; Montal, Mauricio; Tsien, Roger Y.

doi:10.1016/s0092-8674(00)81976-5

Cited by 250 publications

(201 citation statements)

References 53 publications

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“…Proteins from the Rho GTPase family, which are involved in the regulation of endocytotic and exocytotic pathways (46), have been implicated in the regulation of Ca 2ϩ entry in several cell systems (31,(47)(48)(49)(50)(51)(52). Also, in Xenopus oocytes and HEK 293 cells negative modulation of the soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNARE) complex significantly inhibited store-operated Ca 2ϩ entry and I SOC , suggesting that an intact SNARE complex and a process of membrane fusion are required for Ca 2ϩ entry (31,53). SNARE complexes are well known to regulate membrane fusion in regulated exocytosis (for review, see Refs.…”

Section: Discussionmentioning

confidence: 99%

Exocytotic Insertion of TRPC6 Channel into the Plasma Membrane upon Gq Protein-coupled Receptor Activation

Cayouette¹,

Lussier

Mathieu

et al. 2004

Journal of Biological Chemistry

172

126

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TRPC proteins are the mammalian homologues of the Drosophila transient receptor potential channel and are involved in calcium entry after agonist stimulation of non-excitable cells. Seven mammalian TRPCs have been cloned, and their mechanisms of activation and regulation are still the subject of intense research. TRPC proteins interact with the inositol 1,4,5-trisphosphate receptor, and the conformational coupling plays a critical role in the activation of calcium entry. Some evidence also supports an exocytotic mechanism as part of the activation of calcium entry. To investigate the possible involvement of exocytosis in TRPC6 activation, we evaluated the location of TRPC6 at the plasma membrane by biotinylation labeling of cell surface proteins and by indirect immunofluorescence marking of TRPC6 in stably transfected HEK 293 cells. We showed that when the muscarinic receptor was stimulated or the thapsigargin-induced intracellular calcium pool was depleted the level of TRPC6 at the plasma membrane increased. The carbachol concentration at which TRPC6 externalization occurred was lower than the concentration required to activate TRPC6. Externalization occurred within the first 30 s of stimulation, and TRPC6 remained at the plasma membrane as long as the stimulus was present. These results indicate that an exocytotic mechanism is involved in the activation of TRPC6.Increases in intracellular calcium ([Ca 2ϩ ] i ) regulate important cellular functions, including cell growth, differentiation, contraction, and secretion (1, 2). The increase in [Ca 2ϩ ] i is initiated by the activation of phospholipase C␤ or -␥ by a G q protein-coupled receptor or tyrosine kinase receptor, respectively, causing the hydrolysis of phosphatidylinositol 4,5-bisphosphate and generating two-second messengers, inositol 1,4,5-trisphosphate (IP 3 ) 1 and diacylglycerol. IP 3 binds to its specific receptor on the endoplasmic reticulum and causes the first phase of Ca 2ϩ mobilization by releasing Ca 2ϩ from the intracellular pool. The second phase involves Ca 2ϩ entry through the plasma membrane, which maintains [Ca 2ϩ ] i above basal levels. No cellular activity has ever been observed in the absence of this second phase of Ca 2ϩ mobilization.The TRPC protein family is involved in Ca 2ϩ entry (3-5). Seven genes have been identified in the mammalian genome by homology with Drosophila TRP and TRPL, two proteins that are responsible for the light-induced current in insect phototransduction. TRPC channels are probably composed of four subunits, each containing three to four ankyrin-like repeats, two predicted coiled-coil regions (one in the amino terminus and another one in the carboxyl terminus), and a membranespanning region. The amino acids that link the fifth and sixth transmembrane segments form the putative pore region loop. Recent studies on the subunit arrangement of native TRPC in rat brain synaptosomes and the overexpression of TRPC in various systems suggest that the TRPC protein family can be subdivided in two distinct groups and that...

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Section: Discussionmentioning

confidence: 99%

Exocytotic Insertion of TRPC6 Channel into the Plasma Membrane upon Gq Protein-coupled Receptor Activation

Cayouette¹,

Lussier

Mathieu

et al. 2004

Journal of Biological Chemistry

172

126

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“…To investigate this hypothesis, we used Xenopus oocytes as a heterologous expression system for TRPV1 because they recapitulate the properties of PKC signaling (5, 33) and SNARE-dependent exocytosis (33,34). Stimulation of PKC activity was achieved by the incubation of oocytes with 1 M TPA.…”

Section: Fig 6 Potentiation Of Trpv1 Activity By Mglur5 Activationmentioning

confidence: 99%

Regulated Exocytosis Contributes to Protein Kinase C Potentiation of Vanilloid Receptor Activity

Morenilla‐Palao

Planells-Cases

García-Sanz

et al. 2004

Journal of Biological Chemistry

388

302

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The vanilloid receptor-1 (TRPV1) plays a key role in the perception of peripheral thermal and inflammatory pain. TRPV1 expression and channel activity are notably up-regulated by proalgesic agents. The transduction pathways involved in TRPV1 sensitization are still elusive. We have used a yeast two-hybrid screen to identify proteins that associate with the N terminus of TRPV1. We report that two vesicular proteins, Snapin and synaptotagmin IX (Syt IX), strongly interact in vitro and in vivo with the TRPV1 N-terminal domain. In primary dorsal root ganglion neurons, TRPV1 co-distributes in vesicles with Syt IX and the vesicular protein synaptobrevin. Neither Snapin nor Syt IX affected channel function, but they notably inhibited protein kinase C (PKC)-induced potentiation of TRPV1 channel activity with a potency that rivaled the blockade evoked by botulinum neurotoxin A, a potent blocker of neuronal exocytosis. Noteworthily, we found that PKC activation induced a rapid delivery of functional TRPV1 channels to the plasma membrane. Botulinum neurotoxin A blocked the TRPV1 membrane translocation induced by PKC that was activated with a phorbol ester or the metabotropic glutamate receptor mGluR5. Therefore, our results indicate that PKC signaling promotes at least in part the SNARE-dependent exocytosis of TRPV1 to the cell surface. Taken together, these findings imply that activitydependent delivery of channels to the neuronal surface may contribute to the buildup and maintenance of thermal inflammatory hyperalgesia in peripheral nociceptor terminals.TRPV1 1 is a capsaicin-, proton-and heat-sensitive, cationselective ion channel expressed in nociceptors that participates in the transduction of noxious chemical and thermal stimuli by sensory nerve endings in peripheral tissues (1-3). Heterologous expression of TRPV1 cDNA results in ionic currents that recapitulate most of the functional properties displayed by native capsaicin-and heat-activated currents in sensory neurons (1, 2). For instance, TRPV1 exhibits a time-and Ca 2ϩ -dependent desensitization, a long lasting refractory state during which the receptor does not respond to vanilloids or other stimuli (2). In addition, the channel activity of TRPV1 is remarkably upregulated by inflammatory mediators through the activation of phospholipase C and protein kinases A and C (PKA and PKC) signaling pathways (4 -13). Recent evidence shows that an increase in TRPV1 expression in peripheral nociceptors is critical for the maintenance of inflammatory hyperalgesia (14, 15). The involvement of TRPV1 in heat hypersensitivity is further underscored by the reduced sensitivity of mice lacking TRPV1 (16, 17) and by mice treated with receptor-specific antagonists (18).TRPV1 belongs to the family of transient receptor potential channels, which structurally resembles the family of voltagegated potassium or cyclic nucleotide-gated channels (19). Accordingly, these channels are presumed to be tetrameric assemblies of identical subunits (Fig. 1A), although heteromeric assemblies have be...

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“…It is believed that interaction of IP 3 R with TRPC is required for activation of store depletion-induced Ca 2ϩ entry (1,7,8,13,16,(23)(24)(25). Interaction may be in the form of chemical or conformation coupling.…”

mentioning

confidence: 99%

“…Furthermore, this model fails to explain Ca 2ϩ entry by TRPC1 as these channels have been shown to be localized within intracellular membranes (35). These inconsistencies suggest that coupling involves other events such as translocation and docking of IP 3 R and TRPC1 at the plasma membrane (1,23,24,34). Thus, it is possible that proteins capable of trafficking IP 3 R and TRPC1 to the membrane induce association of components of the complex and trigger Ca 2ϩ entry.…”

mentioning

confidence: 99%

RhoA Interaction with Inositol 1,4,5-Trisphosphate Receptor and Transient Receptor Potential Channel-1 Regulates Ca2+ Entry

Mehta

Ahmmed

Paria

et al. 2003

Journal of Biological Chemistry

201

184

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Activation of Store-Operated Ca2+ Current in Xenopus Oocytes Requires SNAP-25 but Not a Diffusible Messenger

Cited by 250 publications

References 53 publications

Exocytotic Insertion of TRPC6 Channel into the Plasma Membrane upon Gq Protein-coupled Receptor Activation

Exocytotic Insertion of TRPC6 Channel into the Plasma Membrane upon Gq Protein-coupled Receptor Activation

Regulated Exocytosis Contributes to Protein Kinase C Potentiation of Vanilloid Receptor Activity

RhoA Interaction with Inositol 1,4,5-Trisphosphate Receptor and Transient Receptor Potential Channel-1 Regulates Ca2+ Entry

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