. Author manuscript; available in PMC: 2009 Jan 2.

Published in final edited form as: Mol Cell Endocrinol. 2007 Oct 6;280(1-2):47–62. doi: 10.1016/j.mce.2007.09.011

Table 3. Kinetic Constants of LXXLL motif mutant ACTRs Binding to TRβ0-DNA Complexes.

Apparent K_d and B_max values for ACTR LXXLL motif mutants binding to TRβ0 complexes on the DR4 (dimers) and consensus rGH (trimers) TREs. N.D. not determinable. Results were obtained as described in Experimental Procedures and for Figure 7. The results of 3 or more assays are shown. Apparent K_d values are in ng coactivator/20 μl reaction and apparent B_max values are expressed as the percent of the original TR/DNA complex supershifted by the coactivator.

		Apparent K_d ± S.E.	Apparent B_max ± S.E.		Apparent K_d ± S.E.	Apparent B_max ± S.E.
Homodimers	wt	15.9 ± 3.91	340 ± 24.1
	mL1	18.8 ± 3.21	457 ± 22.1	mL2, L3	N.D.	N.D.
	mL2	51.8 ± 26.2	174 ± 22.0	mL1, L3	38.9 ± 10.1	341 ± 22.7
	mL3	18.2 ± 2.94	427 ± 19.7	mL1, L2	N.D.	N.D.

Homotrimers	wt	4.18 ± 0.73	314 ± 13.0
	mL1	7.16 ± 3.36	221 ± 28.8	mL2, L3	N.D.	N.D.
	mL2	14.1 ± 2.05	207 ± 8.77	mL1, L3	12.5 ± 2.10	165 ± 8.12
	mL3	6.40 ± 1.10	298 ± 13.9	mL1, L2	N.D.	N.D.

Heterodimers	wt	384 ± 84.9	103 ± 6.05
	mL1	1820 ± 652	175 ± 30.9	mL2, L3	N.D.	N.D.
	mL2	N.D.	N.D.	mL1, L3	667 ± 58.4	131 ± 3.63
	mL3	728 ± 83.2	154 ± 5.80	mL1, L2	N.D.	N.D.

Heterotrimers	wt	15.2 ± 2.67	152 ± 6.67
	mL1	15.9 ± 2.69	146 ± 6.17	mL2, L3	N.D.	N.D.
	mL2	N.D.	N.D.	mL1, L3	13.2 ± 1.45	150 ± 4.11
	mL3	10.4 ± 1.77	144 ± 6.39	mL1, L2	N.D.	N.D.