Sandbox Reserved 1100: Difference between revisions

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The seven transmembrane helices surround a large internal cavity where a <scene name='82/829353/Zinc-binding_site/1'>zinc-binding site</scene> can be found. This cavity located from the cytoplasmic surface to the middle of the outer lipid layer of the membrane has small openings between the helices V and VI, and between the helices IV and VI. It has been assumed that these openings are involved in the entrance and exit of both substrate and product.

In this cavity, there is a zinc ion which is coordinated thanks to three histidine residues. These three histidine residues are <scene name='82/829353/H191/1'>H191</scene> in the helix II, <scene name='82/829353/H337/1'>H337</scene> and <scene name='82/829353/H341/1'>H341</scene> in the helix VII. As a result, the zinc ion is in the intracellular layer of the membrane, in the neighbourhood of 4° deep from the inner surface of the plasma membrane. Thanks to its tetrahedral coordination, this zinc ion binds the helices II, III and VII together. The adiponectin-stimulated AMPK phosphorylation doesn’t directly require the zinc binding site, nevertheless it has been supposed that the zinc ion allows a stabilizing effect.

AdipoR1 has the capacity to form oligomers. Indeed, in living cell both monomers and oligomers are present. A specific motif was identified to contribute to the AdipoR1 dimerization: it is the motif GxxxG in the transmembrane helix 5. Besides, the dimerization of AdipoR1 is also regulated. This dimerization is inhibited by the fixation of the full-length adiponectin while the globular adiponectin has any impact on the dimerization level of the AdipoR1 receptor. Thanks to mutant experiment, it can be supposed that the collagen-like domain of the full-length adiponectin composed of residues 42 to 107 (plus loin dans l’article: 60 à 89…) is responsible to the dimer dissociation. There are strong evidences that dimerization of the AdipoR1 receptor has a role during the biosynthesis, the trafficking and the signalling of the seven transmembrane receptors.

AdipoR1 has the capacity to form oligomers. Indeed, in living cell both monomers and oligomers are present. A specific motif was identified to contribute to the AdipoR1 dimerization: it is the motif GxxxG in the transmembrane helix V. Besides, the dimerization of AdipoR1 is also regulated. This dimerization is inhibited by the fixation of the full-length adiponectin while the globular adiponectin has any impact on the dimerization level of the AdipoR1 receptor. Thanks to mutant experiment, it can be supposed that the collagen-like domain of the full-length adiponectin composed of residues 42 to 107 (plus loin dans l’article: 60 à 89…) is responsible to the dimer dissociation. There are strong evidences that dimerization of the AdipoR1 receptor has a role during the biosynthesis, the trafficking and the signalling of the seven transmembrane receptors.

Sandbox Reserved 1100: Difference between revisions

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 The seven transmembrane helices surround a large internal cavity where a <scene name='82/829353/Zinc-binding_site/1'>zinc-binding site</scene> can be found. This cavity located from the cytoplasmic surface to the middle of the outer lipid layer of the membrane has small openings between the helices V and VI, and between the helices IV and VI. It has been assumed that these openings are involved in the entrance and exit of both substrate and product.
 In this cavity, there is a zinc ion which is coordinated thanks to three histidine residues. These three histidine residues are <scene name='82/829353/H191/1'>H191</scene> in the helix II, <scene name='82/829353/H337/1'>H337</scene> and <scene name='82/829353/H341/1'>H341</scene> in the helix VII. As a result, the zinc ion is in the intracellular layer of the membrane, in the neighbourhood of 4° deep from the inner surface of the plasma membrane. Thanks to its tetrahedral coordination, this zinc ion binds the helices II, III and VII together. The adiponectin-stimulated AMPK phosphorylation doesn’t directly require the zinc binding site, nevertheless it has been supposed that the zinc ion allows a stabilizing effect.
-AdipoR1 has the capacity to form oligomers. Indeed, in living cell both monomers and oligomers are present. A specific motif was identified to contribute to the AdipoR1 dimerization: it is the motif GxxxG in the transmembrane helix 5. Besides, the dimerization of AdipoR1 is also regulated.  This dimerization is inhibited by the fixation of the full-length adiponectin while the globular adiponectin has any impact on the dimerization level of the AdipoR1 receptor. Thanks to mutant experiment, it can be supposed that the collagen-like domain of the full-length adiponectin composed of residues 42 to 107 (plus loin dans l’article: 60 à 89…) is responsible to the dimer dissociation. There are strong evidences that dimerization of the AdipoR1 receptor has a role during the biosynthesis, the trafficking and the signalling of the seven transmembrane receptors.
+AdipoR1 has the capacity to form oligomers. Indeed, in living cell both monomers and oligomers are present. A specific motif was identified to contribute to the AdipoR1 dimerization: it is the motif GxxxG in the transmembrane helix V. Besides, the dimerization of AdipoR1 is also regulated.  This dimerization is inhibited by the fixation of the full-length adiponectin while the globular adiponectin has any impact on the dimerization level of the AdipoR1 receptor. Thanks to mutant experiment, it can be supposed that the collagen-like domain of the full-length adiponectin composed of residues 42 to 107 (plus loin dans l’article: 60 à 89…) is responsible to the dimer dissociation. There are strong evidences that dimerization of the AdipoR1 receptor has a role during the biosynthesis, the trafficking and the signalling of the seven transmembrane receptors.