Sandbox Reserved 1719: Difference between revisions
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<scene name='90/904324/Active_site_residues/8'>Sub-pocket 2</scene> is formed by TM1, TM2, TM6, and TM7.<ref name="Can"/> This binding sub-pocket is much broader and allows for the binding of larger structures ('''Figure 3B''').<ref name="Can"/> The key residues involved are Trp243 and Phe170 that contributes to the high hydrophobicity of the binding pocket.<ref name="Can"/> The hydrophobicity of this binding pocket accounts for the large electrostatic difference observed between the two sub pockets demonstrated in '''Figure 2'''. | <scene name='90/904324/Active_site_residues/8'>Sub-pocket 2</scene> is formed by TM1, TM2, TM6, and TM7.<ref name="Can"/> This binding sub-pocket is much broader and allows for the binding of larger structures ('''Figure 3B''').<ref name="Can"/> The key residues involved are Trp243 and Phe170 that contributes to the high hydrophobicity of the binding pocket.<ref name="Can"/> The hydrophobicity of this binding pocket accounts for the large electrostatic difference observed between the two sub pockets demonstrated in '''Figure 2'''. | ||
[[Image:Screen Shot 2022-04-18 at 1.35.31 PM.png| | [[Image:Screen Shot 2022-04-18 at 1.35.31 PM.png|500px|center|thumb|'''Figure 3.''' (A). Cross-sectional views of electrostatic surface of MRGPRX2 sub-pocket 1 interaction with lysine 3 and (B) sub-pocket 2 interaction with phenylalanine 6 of cortistatin-14.]] | ||
== Ligand interactions == | == Ligand interactions == | ||
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The conformations of the G-proteins vary based on their association with a particular membrane receptor due to interactions between the amino acids in the N-terminus of the α subunit and the C-terminus of the receptor.<ref name="Kamato"/> | The conformations of the G-proteins vary based on their association with a particular membrane receptor due to interactions between the amino acids in the N-terminus of the α subunit and the C-terminus of the receptor.<ref name="Kamato"/> | ||
[[Image:Mast cell mechanism.png| | [[Image:Mast cell mechanism.png|500px|right|thumb|'''Figure 8.''' Cellular response of mast cell upon activation of MRGPRX2.]] | ||
Binding to the extracellular N-terminus domain triggers a transmembrane conformation change of MRGPRX2, which demonstrates a less significant change when compared to other class A GPCRs due to the surface level binding of the ligand to MRGPRX2.<ref name="Can"/> Once ligand binding and the conformational change to the active state have taken place, the signal is relayed to the α-subunit of the heterotrimeric G-protein.<ref name="nelson"/> The α-subunit will then exchange a GDP for GTP to initiate the dissociation of the α, β, and γ subunits.<ref name="nelson"/> During this dissociation, the α-subunit is able to travel away from the receptor in the plane of the membrane to bind to downstream effectors to produce a cellular response.<ref name="nelson"/> | Binding to the extracellular N-terminus domain triggers a transmembrane conformation change of MRGPRX2, which demonstrates a less significant change when compared to other class A GPCRs due to the surface level binding of the ligand to MRGPRX2.<ref name="Can"/> Once ligand binding and the conformational change to the active state have taken place, the signal is relayed to the α-subunit of the heterotrimeric G-protein.<ref name="nelson"/> The α-subunit will then exchange a GDP for GTP to initiate the dissociation of the α, β, and γ subunits.<ref name="nelson"/> During this dissociation, the α-subunit is able to travel away from the receptor in the plane of the membrane to bind to downstream effectors to produce a cellular response.<ref name="nelson"/> | ||
