Table 2. Data collection and refinement statistics for molecular replacement.

	QUA1-KH–UAAU	STAR–AUUAAA	KH-QUA2–AAUAAU	KH–AAAUAA
Data collection
Beamline	Diamond I03	Diamond I03	Diamond I04-1	Diamond I04-1
Space group	P 1 21 1	P 1 21 1	P 21 21 21	C 2 2 21
Cell dimensions
a, b, c (Å)	54.88, 46.06, 83.98	51.601, 79.967, 53.831	42.38, 45.56, 151.98	93.73, 162.22, 113.04
α, β, γ (°)	90, 96.36, 90	90, 101.05, 90	90, 90, 90	90, 90, 90
Resolution (Å)	43.5–2.13 (2.206–2.13)	25.68–3.03 (3.138–3.03)	43.64–2.3 (2.382–2.3)	81.16–2.87 (3.02–2.87)
Rmerge	0.05636 (0.6557)	0.08798 (0.3612)	0.08045 (0.8574)	0.1907 (0.7811)
CC1/2	0.999 (0.849)	0.988 (0.8)	0.998 (0.898)	0.989 (0.7)
CC*	1 (0.958)	0.997 (0.939)	1 (0.973)	0.997 (0.908)
I/σI	18.29 (3.26)	8.10 (1.96)	21.25 (3.32)	8.07 (2.53)
Completeness (%)	0.99 (1.00)	0.94 (0.93)	1.00 (1.00)	99.83 (99.03)
Redundancy	6.5 (6.6)	2.6 (2.6)	12.6 (12.9)	6.9 (7.2)
Wilson B-factor	47.40	55.64	46.13	49.63
Twin fraction	—	—	—	0.198
Refinement
Resolution (Å)	43.5–2.13 (2.206–2.13)	28.51–3.03 (3.138–3.03)	43.64–2.3 (2.382–2.3)	81.16–2.87 (3.02–2.87)
No. of reflections
Total	153,246 (15,486)	20,330 (1,967)	173,701 (17,282)	137,428 (14,177)
Unique	23,555 (2,352)	7,888 (771)	13,734 (1,340)	20,040 (1,962)
Rwork/Rfree	0.2043–0.2565 (0.2815–0.3532)	0.2207–0.2693 (0.2894–0.3744)	0.2273–0.2694 (0.2641–0.3884)	0.1875–0.2358 (0.2583–0.3236)
No. of atoms	2,597	2,606	1,927	5,631
Protein	2,418	2,350	1,800	5,356
RNA	168	256	106	260
Ion	0	0	0	15
Water	11	0	21	0
B-factors	66.46	55.88	56.71	52.05
Protein	66.31	55.93	56.60	52.62
RNA	69.98	55.39	60.44	39.89
Ion	—	—	—	46.08
Water	45.43	—	47.48	—
Root mean squared deviations
Bond lengths (Å)	0.015	0.003	0.015	0.013
Bond angles (°)	1.51	0.669	1.81	1.46
Ramachandran plot
% Favoured	96	98	98	95
% Outliers	0.34	0.35	0	1.5
Molprobity
Clashcores	14.83	5.04	3.91	20.6