Table 1.

Binding kinetics and affinities for the interactions of mouse WT sNASP and rec1c variant sNASP proteins with mouse histones H1a, H3.1, H4, and H3.1/H4 tetramer.

	Kon (1/Ms)		Koff (1s)		Kd (nM)
	Mean	SEM	Mean	SEM	Mean	SEM	P-value
H1a BINDING
WT sNASP	1.006 × 104	0.0281 × 104	3.89 × 10−4	0.337 × 10−4	387	11.3	p > 0.05
sNASP variant	0.959 × 104	0.0281 × 104	3.95 × 10−4	0.353 × 10−4	412	12.6
H3.1 BINDING
WT sNASP	0.869 × 104	0.0088 × 104	1.181 × 10−4	0.105 × 10−4	13.6	1.21	p > 0.05
sNASP variant	0.895 × 104	0.0094 × 104	0.755 × 10−4	0.144 × 10−4	8.45	1.61
H4 BINDING
WT sNASP	0.199 × 104	0.0010 × 104	0.81 × 10−4	0.054 × 10−4	40.7	3.6	p < 0.01
sNASP variant	1.587 × 104	0.0147 × 104	3.68 × 10−4	0.123 × 10−4	23.2	0.81
H3.1/H4 TETRAMER BINDING
WT sNASP	2.44 × 104	0.076 × 104	9.78 × 10−4	0.700 × 10−4	40.2	3.14	p < 0.01
sNASP variant	3.72 × 104	0.117 × 104	5.39 × 10−4	0.549 × 10−4	14.5	1.54

Quantitative binding studies of the interactions of mouse WT sNASP and rec1c variant sNASP proteins with mouse histones H1a, H3.1, H4, and H3.1/H4 tetramer were measured using biolayer interferometer. The binding kinetic parameters were determined from four separate experiments (n = 4). Values in the table indicate mean and SEM (standard error of mean). Calculated K_d = k_off /k_on.