TABLE 1

Effects glutamate substitutions in the Ca²⁺ channel pore have on Ca²⁺ and DHP binding parameters

Values are means ± S.E.M.

	K_D1	αK_D1	K_C1	αK_C1	α
	nM (-fold change)		αM (-fold change)		-fold change
Wild type	0.31 ± 0.031	4.8 ± 0.59	0.040 ± 0.005	0.62 ± 0.10	15.5 ± 1.90
E292Q	0.93 ± 0.15 (3)^*	50.7 ± 10 (10.6)^*	0.462 ± 0.08 (11.6)^*	23.0 ± 1.5 (37)^*	54.5 ± 11.3 (3.5)^*
E614Q	2.68 ± 1.4 (8.6)^*	13.5 ± 3.1 (2.8)^*	5.83 ± 0.83 (146)^*	29.2 ± 6.6 (47)^*	5.11 ± 1.32 (0.3)
E1014Q	1.71 ± 0.29 (5.5)^*	7.71 ± 0.80 (1.6)	3.72 ± 1.74 (93)^*	20.6 ± 4.1 (33)^*	4.45 ± 0.48 (0.3)^*
E1323Q	2.88 ± 0.50 (9.3)^*	28.1 ± 3.7 (5.8)^*	4.05 ± 0.10 (101)^*	35.6 ± 2.3 (57)^*	9.75 ± 1.3 (0.6)
E292K	2.69 ± 0.73 (8.7)^*	17.3 ± 4.0 (3.6)^*	6.17 ± 1.9 (154)^*	34.4 ± 2.6 (55)^*	6.40 ± 1.5 (0.4)
E614K	N.D.	N.D.	N.D.	N.D.	N.D.
E1014K	2.98 ± 0.68 (9.6)^*	3.98 ± 0.25 (0.8)	4.20 ± 2.6 (105)^*	5.42 ± 3.1 (8.7)^*	1.33 ± 0.09 (0.1)^*
E1323K	N.D.	N.D.	N.D.	N.D.	N.D.

N.D., not determined.
↵* Values that are significantly different from wild type, as determined by the Student's independent t test (P < 0.05). Each value is determined from 3 to 14 experiments (see Materials and Methods for details).