Protein Origami

Two modifications of the GnRHR associated with altered expression. Addition of K¹⁹¹, an “extra” amino acid that appears in humans and other primates is associated with diminished receptor expression at the plasma, membrane. Pre-mammalian animals (fish, birds) have a C-terminal tail extension, absent in mammals, that enhances expression of the receptor. Accordingly, the tendency is to evolve a receptor that can be more closely regulated due to diminished expression.