Beta2 adrenergic receptor-Gs protein complex: Difference between revisions
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[[Image:G protein cycle for the b2AR–Gs complex.JPG|left|thumb|G protein cycle for the b2AR–Gs complex. Reprinted by permission from Macmillan Publishers Ltd on behalf of Cancer Research UK: Nature 477, 549–555, copyright 2011]] | [[Image:G protein cycle for the b2AR–Gs complex.JPG|left|thumb|G protein cycle for the b2AR–Gs complex. Reprinted by permission from Macmillan Publishers Ltd on behalf of Cancer Research UK: Nature 477, 549–555, copyright 2011]] | ||
The figure shows the G Protein cycle <ref>doi:10.1038/nature10361</ref> - an extracellular agonist binds to the β2AR leads [[Group:SMART:A Physical Model of the β2-Adrenergic Receptor|to conformational rearrangements of the cytoplasmic ends of transmembrane segments]] that enable the Gs heterotrimer to bind the receptor. GDP is released from the α subunit upon formation of β2AR–Gs complex. The GTP binds to the nucleotide-free α subunit resulting in dissociation of the α and βγ subunits from the receptor. The subunits regulate their respective effector proteins adenylyl cyclase (AC) and Ca2+ channels. The Gs heterotrimer reassembles from α and βγ subunits following hydrolysis of GTP to GDP in the α subunit. | The figure shows the G Protein cycle <ref>doi:10.1038/nature10361</ref> - an extracellular agonist binds to the β2AR leads [[Group:SMART:A Physical Model of the β2-Adrenergic Receptor|to conformational rearrangements of the cytoplasmic ends of transmembrane segments]] that enable the Gs heterotrimer to bind the receptor. GDP is released from the α subunit upon formation of β2AR–Gs complex. The GTP binds to the nucleotide-free α subunit resulting in dissociation of the α and βγ subunits from the receptor. The subunits regulate their respective effector proteins adenylyl cyclase (AC) and Ca2+ channels. The Gs heterotrimer reassembles from α and βγ subunits following hydrolysis of GTP to GDP in the α subunit. | ||
The Gαs subunit consists of two domains, the Ras domain (αRas) and the α-helical domain (αAH). Both are involved in nucleotide binding. In the nucleotide-free state, the αAH domain has a variable position relative the αRas domain. | The Gαs subunit consists of two domains, the Ras domain (αRas) and the α-helical domain (αAH). Both are involved in nucleotide binding. In the nucleotide-free state, the αAH domain has a variable position relative the αRas domain. | ||
==See Also== | ==See Also== | ||