複選題36. Which of the following statements about protein phosphorylation is (are) CORRECT? (A) Phosphorylation is an important way to modulate enzymatic activity: phosphorylated enzymes are active and dephosphorylated enzymes are all inactive and will be degraded (B) Receptor tyrosine kinase undergoes autophosphorylation and adds phosphate group to itself on the same molecule (C) Mutations of a serine residue that is normally phosphorylated to aspartic acid often mimic the effects of phosphorylation (D) Phosphorylation of a protein could trigger its degradation by the proteasome (E) Phosphorylation could serve as a localizing signal to retain the protein in the cytosol or localizes it to the nucleus