TABLE 1. The efficiency of [¹²⁵I]TID photoincorporation in amino acids within the δ subunit (cpm/pmol of PTH-derivative).

The ¹²⁵I incorporation in each residue was calculated from the observed ¹²⁵I release as described under “Experimental Procedures”, and the mass was calculated from the initial and repetitive yield.

		Native Torpedo nAChR				Purified Torpedo nAChR
		Experiment I		Experiment II		Experiment III
		Control	Carb	Carb	Carb and PCP	Control	Carb
δM2-6	Ser262	< 0.3	0.6	1.7	<0.1	0.5	0.9
δM2-9	Leu265	43	1.4	2.5	5.2	17	0.7
δM2-13	Val269	130	2.4	3.3	3.9	44	1.2
δM2-18	Thr274	< 0.3	15	23	16	1.3	4.6
δ M2-M3	Ile288	1.0	6.5	11	6.4	0.8	0.8
δ M1	Phe232	< 0.5	5.0	8.3	4.4	1.0	1.6
	Cys236	1.0	42	38	15	2.3	4.6
αM4	Cys412	7.7	13	38	41	100	80