Serotonin

DOPA decarboxylase (DDC) is responsible for catalyzing the conversion of aromatic amino acids into their corresponding amines during the synthesis of several important neurotransmitters. Specifically, DDC catalyzes the decarboxylation of L-DOPA to dopamine, L5-HTP to serotonin, L-histidine to histamine, phenylalanine to phenethylamine, L-tyrosine to tyramine, and tryptophan to tryptamine.

The beta-arrestin family regulate receptor binding of G-proteins, a group of seven transmembrane receptor proteins which includes the adrenergic, dopamine and serotonin receptors. Recently, arrestin antibodies were used in a study into Serotonin Syndrome, a hallucinogenic disorder which can follow SSRI (selective serotonin reuptake inhibitor) use.