Which cell-surface receptor do glucagon and adrenaline utilise? Describe it's functionality.
The G-coupled protein receptor. Consists of 7-transmembrane subunits. When a receptor is activated, it induces conformational change in the Gα subunit, which dissociates GDP and binds GTP, becoming active. Gα dissociates from other subunits and activates effector molecule. GTP is hydrolysed to GDP, Gα reassociates with subunits.