TABLE 1.

Alanine scanning of mNop5p activity

Mutant	KD	Krela	ΔΔ G	p value (t test)b
	nm		kcal/mol
Wild typec	76 ± 6	1
K32A	190 ± 31	2.5	−0.54	0.0033
E44A	87 ± 37	1.1	−0.06	0.6380
K47A	71 ± 17	0.93	0.04	0.6560
E100A	140 ± 17	1.8	−0.35	0.0035
E104A	91 ± 15	1.2	−0.11	0.1831
F107A	83 ± 12	1.1	−0.06	0.4173
N112A	200 ± 62	2.6	−0.57	0.0261
K131A	64 ± 8	0.84	0.10	0.1062
D253A	120 ± 9	1.6	−0.28	0.0021
K265A	62 ± 11	0.81	0.12	0.1251
E279A	210 ± 41	2.7	−0.59	0.0050
S286A	600 ± 60	7.9	−1.22	0.0001
T287A	230 ± 6	3.0	−0.65	0.0001
Q289A	1500 ± 81	20	−1.77	0.0001
R299A	57 ± 11	0.75	0.17	0.0584
K306A	87 ± 20	1.1	−0.06	0.4132
N320A	140 ± 3	1.8	−0.35	0.0001
W324A	150 ± 13	2.0	−0.41	0.0009
Q326A	280 ± 9	3.7	−0.78	0.0001
R327A	50 ± 6	0.66	0.25	0.0061
K329A	210 ± 3	2.8	−0.61	0.0001
R332A	1600 ± 240	21	−1.80	0.0004
K337A	360 ± 23	4.7	−0.92	0.0001
F347A	760 ± 100	10	−1.36	0.0003
E350A	150 ± 12	2.0	−0.41	0.0007
E354A	140 ± 24	1.8	−0.35	0.0110
E361A	110 ± 23	1.4	−0.20	0.0684
R363A	400 ± 34	5.3	−0.99	0.0001
K365A	130 ± 15	1.7	−0.31	0.0044
E366A	260 ± 37	3.4	−0.72	0.0010
K368A	130 ± 3	1.7	−0.31	0.0002

^aK_rel = K_D,mutant/K_{D,wild type}.

^bp values from a two-tailed unpaired t test. The mutations to mNop5p that result in a statistically significant change in binding affinity relative to wild type are listed in bold type (95% confidence level).

^cWild type refers to the mNop5p protein that contains a deletion of the coiled-coil domain of Nop5, preventing its dimerization.