123 research outputs found
Ubiquitination of CXCR7 Controls Receptor Trafficking
The chemokine receptor CXCR7 binds CXCL11 and CXCL12 with high affinity, chemokines that were previously thought to bind exclusively to CXCR4 and CXCR3, respectively. Expression of CXCR7 has been associated with cardiac development as well as with tumor growth and progression. Despite having all the canonical features of G protein-coupled receptors (GPCRs), the signalling pathways following CXCR7 activation remain controversial, since unlike typical chemokine receptors, CXCR7 fails to activate Gαi-proteins. CXCR7 has recently been shown to interact with β-arrestins and such interaction has been suggested to be responsible for G protein-independent signals through ERK-1/2 phosphorylation. Signal transduction by CXCR7 is controlled at the membrane by the process of GPCR trafficking. In the present study we investigated the regulatory processes triggered by CXCR7 activation as well as the molecular interactions that participate in such processes. We show that, CXCR7 internalizes and recycles back to the cell surface after agonist exposure, and that internalization is not only β-arrestin-mediated but also dependent on the Serine/Threonine residues at the C-terminus of the receptor. Furthermore we describe, for the first time, the constitutive ubiquitination of CXCR7. Such ubiquitination is a key modification responsible for the correct trafficking of CXCR7 from and to the plasma membrane. Moreover, we found that CXCR7 is reversibly de-ubiquitinated upon treatment with CXCL12. Finally, we have also identified the Lysine residues at the C-terminus of CXCR7 to be essential for receptor cell surface delivery. Together these data demonstrate the differential regulation of CXCR7 compared to the related CXCR3 and CXCR4 receptors, and highlight the importance of understanding the molecular determinants responsible for this process
Receptor Heteromerization Expands the Repertoire of Cannabinoid Signaling in Rodent Neurons
A fundamental question in G protein coupled receptor biology is how a single ligand acting at a specific receptor is able to induce a range of signaling that results in a variety of physiological responses. We focused on Type 1 cannabinoid receptor (CB1R) as a model GPCR involved in a variety of processes spanning from analgesia and euphoria to neuronal development, survival and differentiation. We examined receptor dimerization as a possible mechanism underlying expanded signaling responses by a single ligand and focused on interactions between CB1R and delta opioid receptor (DOR). Using co-immunoprecipitation assays as well as analysis of changes in receptor subcellular localization upon co-expression, we show that CB1R and DOR form receptor heteromers. We find that heteromerization affects receptor signaling since the potency of the CB1R ligand to stimulate G-protein activity is increased in the absence of DOR, suggesting that the decrease in CB1R activity in the presence of DOR could, at least in part, be due to heteromerization. We also find that the decrease in activity is associated with enhanced PLC-dependent recruitment of arrestin3 to the CB1R-DOR complex, suggesting that interaction with DOR enhances arrestin-mediated CB1R desensitization. Additionally, presence of DOR facilitates signaling via a new CB1R-mediated anti-apoptotic pathway leading to enhanced neuronal survival. Taken together, these results support a role for CB1R-DOR heteromerization in diversification of endocannabinoid signaling and highlight the importance of heteromer-directed signal trafficking in enhancing the repertoire of GPCR signaling
Circadian-Related Heteromerization of Adrenergic and Dopamine D4 Receptors Modulates Melatonin Synthesis and Release in the Pineal Gland
Dopamine and adrenergic receptor complexes form under a circadian-regulated cycle and directly modulate melatonin synthesis and release from the pineal gland
Circadian-Related Heteromerization of Adrenergic and Dopamine D4 Receptors Modulates Melatonin Synthesis and Release in the Pineal Gland
Dopamine and adrenergic receptor complexes form under a circadian-regulated cycle and directly modulate melatonin synthesis and release from the pineal gland
C-X-C motif chemokine 12/C-X-C chemokine receptor type 7 signaling regulates breast cancer growth and metastasis by modulating the tumor microenvironment
E. Preobrajensky, De la N.E.P. au socialisme, vues sur l'avenir de la Russie et de l'Europe, préface de Pierre Naville
Decaillot Maurice. E. Preobrajensky, De la N.E.P. au socialisme, vues sur l'avenir de la Russie et de l'Europe, préface de Pierre Naville . In: Revue de l'Est, vol. 2, 1971, n°3. p. 198
E. Preobrajensky. De la N.E.P. au socialisme, vues sur l'avenir de la Russie et de l'Europe, préface de Pierre Naville
Decaillot Maurice. E. Preobrajensky. De la N.E.P. au socialisme, vues sur l'avenir de la Russie et de l'Europe, préface de Pierre Naville. In: Revue de l'Est, vol. 1, 1970, n°2. pp. 159-163
Jean-Jacques Gauthé ; Gérard Cholvy (Préf.), Le scoutisme en France : inventaire de la bibliographie et des sources, Montpellier, Centre régional d'histoire des mentalités-Université Paul-Valéry, 1997
Decaillot Éliane. Jean-Jacques Gauthé ; Gérard Cholvy (Préf.), Le scoutisme en France : inventaire de la bibliographie et des sources, Montpellier, Centre régional d'histoire des mentalités-Université Paul-Valéry, 1997. In: Histoire de l'éducation. n° 81, 1999. pp. 155-156
Wallis A., Socjologia wielkiego miasta [Sociologie de la grande ville].
Decaillot Maurice. Wallis A., Socjologia wielkiego miasta [Sociologie de la grande ville].. In: Revue française de sociologie, 1968, 9-2. p. 274
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