Table S1.

X-ray data collection and refinement statistics

Crystallographic data	mAHR–hARNT–DRE complex
Data collection
Beamline	LS-CAT ID-F and G
Wavelength, Å	0.97872
Space group	C121
Cell dimension
a, b, c, Å	78.199, 64.364, 157.725,
α, β, γ, °	90, 100.136, 90
Resolution, Å	50–3.9 (3.97–3.90)
Total no. of reflections	63,522
No. of unique reflections	6,690 (669)
I/σ (I)	11.0 (1.5)
Multiplicity*	7.9 (5.9)
Completeness, %	99.50 (96.00)
Refinement
Resolution, Å	39.7–4.0 (4.14–4.0)
Rwork†/Rfree‡, %	28.52/32.26
No. of atoms*	3,476/2,769/640/67
B factor*, Å2	222.1/214.0/256.2/232.4
rmsd bonds, Å	0.010
rmsd angles, °	1.30
Ramachandran plot§, %	91.0/8.1/0.9

The values in parentheses indicate the highest resolution shell (resolution range: 3.97–3.90 Å for data collection and 4.14–4.0 Å for refinement).

^*All atoms/protein/DNA/ligand.

^†Σ_hkl ||F_obs| − k|F_calc||/ Σ_hkl |F_obs|.

^‡R_free was calculated by the same way as R_work, but with the 5% of the reflections excluded from the refinement.

^§Preferred region/allowed region/disallowed region.