Table 4.

Amino Acid Residues Important for Zinc Modulation of GlyR Function

GlyR	Potentiating sites				Inhibitory sites
α1	D80	T151	E192	D194	H215	H107*	H109	T112	T133
α2	D87	T158	E199	E201*	H222	N114	H116	T119	T140
α3	D80	T151	E192	D194	H215	N107	H109	T112	T133

Summary of the amino acid residues important for zinc action at GlyRs. Alignment of the amino acid sequences for the α1-, α2-, and α3-GlyR subunits reveals that of the known putative zinc-binding sites at the GlyR, all are conserved in these 3 subunits except for 2 positions (*), H107 in α1 and E201 in α2. Each of the amino acid residues listed has been shown to be important either for high-affinity zinc binding and enhancement of GlyR function or for lower affinity zinc binding and inhibition of GlyR function (Laube et al., 2000; Miller et al., 2005a,b).