errata 23068

modules/m62798/index.cnxml

@@ -174,7 +174,7 @@
 <image mime-type="image/jpg" src="../../media/Figure_09_01_04-11d6.jpg" width="320"/>
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 <caption>Gated ion channels form a pore through the plasma membrane that opens when the signaling molecule binds. The open pore then allows ions to flow into or out of the cell.</caption></figure><para id="fs-id2592121"><term id="term-00019">G-protein-linked receptors</term> bind a ligand and activate a membrane protein called a G-protein. The activated G-protein then interacts with either an ion channel or an enzyme in the membrane (<link target-id="fig-ch09_01_05"/>). All G-protein-linked receptors have seven transmembrane domains, but each receptor has its own specific extracellular domain and G-protein-binding site.</para>
-<para id="fs-id2336863">Cell signaling using G-protein-linked receptors occurs as a cyclic series of events. Before the ligand binds, the inactive G-protein can bind to a newly revealed site on the receptor specific for its binding. Once the G-protein binds to the receptor, the resultant shape change activates the G-protein, which releases GDP and picks up GTP.  The subunits of the G-protein then split into the <emphasis effect="italics">α</emphasis> subunit and the <emphasis effect="italics">βγ</emphasis> subunit.  One or both of these G-protein fragments may be able to activate other proteins as a result.  After awhile, the GTP on the active <emphasis effect="italics">α</emphasis> subunit of the G-protein is hydrolyzed to GDP and the <emphasis effect="italics">βγ</emphasis> subunit is deactivated.  The subunits reassociate to form the inactive G-protein and the cycle begins anew.</para>
+<para id="fs-id2336863">Cell signaling using G-protein-linked receptors occurs as a cyclic series of events. Before the ligand binds, the inactive G-protein can bind to a newly revealed site on the receptor specific for its binding. Once the signaling molecule binds to the receptor, the resultant shape change activates the G-protein, which releases GDP and picks up GTP.  The subunits of the G-protein then split into the <emphasis effect="italics">α</emphasis> subunit and the <emphasis effect="italics">βγ</emphasis> subunit.  One or both of these G-protein fragments may be able to activate other proteins as a result.  After awhile, the GTP on the active <emphasis effect="italics">α</emphasis> subunit of the G-protein is hydrolyzed to GDP and the <emphasis effect="italics">βγ</emphasis> subunit is deactivated.  The subunits reassociate to form the inactive G-protein and the cycle begins anew.</para>
 <figure id="fig-ch09_01_05" class="ost-tag-lo-apbio-ch09-s01-lo02 ost-tag-lo-apbio-ch09-s01-aplo-3-35"><media id="fs-id1778091" alt="This illustration shows the activation pathway for a heterotrimeric G-protein, which has three subunits: alpha beta, and gamma, all associated with the inside of the plasma membrane. When a signaling molecule binds to a G-protein-coupled receptor in the plasma membrane, a GDP molecule associated with the alpha subunit is exchanged for GTP. The alpha subunit dissociates from the beta and gamma subunits and triggers a cellular response. Hydrolysis of GTP to GDP terminates the signal.">
 <image mime-type="image/jpg" src="../../media/Figure_09_01_05.jpg" width="400"/>
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