Fig. 4. Comparison of Norepi binding for α_2A and β adrenergic receptors.

(A) Detailed interactions of Norepi with β₁AR [Protein Data Bank (PDB) code: 7BU6]. Residues within 4 Å of agonist are shown in sticks. The polar interactions are indicated by black dashed lines. (B) Superposition of orthosteric pockets of β₁AR-Norepi and β₂AR-Epi (epinephrine) (PDB code: 4LDO). (C) Detailed interactions of dopamine with D1R (PDB code: 7CKZ). The polar interactions are indicated by black dashed lines. (D) Superposition of orthosteric pockets of β₁AR-Norepi and α_2AAR-Norepi. Residues within 4 Å of agonist are shown in sticks.