Table 1.

AChR ligand binding site multiloop structure

Loop	Residue Span	Secondary Structure	Key Residues	Defining Ligands
A	α93-97	β4-β5 linker	Tyr93, Ala96, Asp97	Nicotine, ACh
B	α148-153	β7-β8 linker	Trp149, Tyr151, Gly153	Nicotine, ACh, d-tubocurarine
C	α189-200	β9-β10 linker	Tyr190, Cys192, Cys193, Tyr198, Asp200	Nicotine, ACh, bromo-ACh, lophotoxin
D	ε55-59, δ57-61	β2-strand	εTrp55, εGly57, εAsp59, δTrp57, δGlu59, δGly61	d-Tubocurarine, metocurine, nicotine, ACh, NmmI α-toxin, Waglerin I
E	ε109-119, δ111-121	β5′-β6-strands	εLeu109, εTyr111, εVal116, εThr117, εLeu119, δLeu111, δTyr113, δVal118, δTyr119, δLeu121	α-Conotoxin M1, d-tubocurarine, metocurine, α -bungarotoxin, NmmI α-toxin, Waglerin I
F	ε161-183, δ163-187	β8-β9 linker	εAsp173, εAsp175, δIle178, δAsp180	α-Conotoxin M1, metocurine, NmmI α-toxin, ACh, Waglerin I
G	ε29-45, δ31-47	β1-strand	εLys34, δAla36	α-Conotoxin M1, carbamylcholine

Residue positions correspond to the human endplate AChR.