Which of the following events normally activates a GTP-binding protein?a).GTP hydrolysis by the protein Activation of an upstrea
m GTPase-activating proteinb).Activation of an upstream guanine nucleotide exchange factorc). Phosphorylation of a bound GDP molecule by an upstream phosphorylased). Pi release after GTP hydrolysis
b). Activation of an upstream guanine nucleotide exchange factor
<h3><u>Explanation</u>;</h3>
<em><u>When a ligand activates the G protein-coupled receptor, it induces a conformational change in the receptor that allows the receptor to function as a guanine nucleotide exchange factor (GEF) that exchanges GDP for GTPthus turning the G protein-coupled receptor on.</u></em>
The activated G-protein then dissociates into an alpha (G-alpha) and a beta-gamma complex.
To protect our eyes from moisture and light. Example: from sweat. It can also reduce the amount of light that gets in your eyes and keep dirt away from them too.