Table. 1. Summary of the complementary interfaces identified in the crystal structures of GPCRs; h-h and h-t account for, respectively, head-to-head (two-fold rotational symmetry) and head-to-tail (translational symmetry) interactions.

PDB id Macromolecule name Class Interface References2YCY, 4GPO β1 adrenergic receptor

(turkey)A h-h TM1 (Huang et al., 2013,

Moukhametzianov et al., 2011)

2RH1 β2 adrenergic receptor (human)

A h-h TM1 (Cherezov et al., 2007)

3OE9 C-X-C chemokine receptor type 4 (human)

A h-h TM1 (Wu et al., 2010)

4DJH κ-type opioid receptor (human)

A h-h TM1 (Wu et al., 2012)

4OR2 Metabotropic glutamate receptor 1 (human)

C h-h TM1 (Wu et al., 2014)

4DKL μ-type opioid receptor (human)

A h-h TM1 (Manglik et al., 2012)

4U15, 4U16 Muscarinic acetylcholine receptor M3 (rat)

A h-h TM1 (Thorsen et al., 2014)

2I35, 2I36, 2I37, 2X72, 3CAP, 3DQB, 3PQR, 3PXO, 4A4M, 4BEY, 4BEZ, 4J4Q

(Rhod)opsin (bovine) A h-h TM1 (Choe et al., 2011, Deupi et al., 2012, Park et al., 2013, Park et al., 2008, Salom et al., 2006, Scheerer et al., 2008, Singhal et al., 2013)

3RZE Histamine H1 receptor (human)

A h-h TM4 * (Shimamura et al., 2011)

4EIY Adenosine receptor A2a (human)

A h-h TM4/5 (Liu et al., 2012)

4GPO Beta-1 adrenergic receptor (turkey)

A h-h TM4/5 (Huang et al., 2013)

2Z73, 3AYM, 3AYN

Rhodopsin (squid) A h-h TM4/5 (Murakami and Kouyama, 2008, Murakami and Kouyama, 2011)

4JKV Smoothened homolog (human)

F h-h TM4/5 (Wang et al., 2013)

4BVN Beta-1 adrenergic receptor (turkey)

A h-h TM5 (Miller-Gallacher et al., 2014)

3ODU, 3OE0, 3OE6, 3OE8, 3OE9

C-X-C chemokine receptor type 4 (human)

A h-h TM5 (Wu et al., 2010)

2ZIY, 2Z73, 3AYM, 3AYN

Rhodopsin (squid) A h-h TM5 (Shimamura et al., 2008)

4DKL, Mu-type opioid receptor A h-h TM5/6 * (Manglik et al., 2012)4NTJ P2Y purinoceptor 12 A h-h TM5/6 *4MBS C-C chemokine

receptor type 5 (human)

A h-t TM1-TM4 * (Tan et al., 2013)

3OE8 C-X-C chemokine receptor type 4 (human)

A h-t TM1-TM4 * (Wu et al., 2010)

3OE8 C-X-C chemokine receptor type 4 (human)

A h-t TM1-TM5/6 * (Wu et al., 2010)

* This interface may be altered by the presence of T4L (T4 lysozyme) or BRIL (thermostabilized apocytochrome b562).

Supplemental References

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