Table 2.

Interhelical Distances

data seta		inter-R5 distance (Å)
		DEER measuredb	EPR-based modelc	crystal structured
HT vs HL	(76; 95)	28	26.4	27.6
	(79; 95)	38	37.5	38.0
	(88; 95)	34	30.3	29.7
	(26; 76)	28e	30.7	23.7
	(26; 79)	35e	31.6	30.1
	(26; 88)	37	37.2	10.7
HT vs HR	(26; 37)	39	38.6	44.8
	(33; 95)	32e	30.4	40.8
	(37; 95)	40	43.4	45.5
	(66; 95)	30e	25.9	22.8
HR vs HL	(33; 76)	39	41.0	23.5
	(33; 79)	44	43.0	38.1
	(37; 76)	48	50.8	36.4
	(37; 79)	49	47.4	52.6
	(37; 88)	40	39.3	50.2
	(66; 76)	35	38.8	18.8
	(66; 79)	41	39.1	35.6
RMSDdeer		-	2.43	10.2

^aEach designated by corresponding labeling site numbers.

^bMost probable distances listed. Estimated errors are less than 7% based on repeated measurements.

^cInter-NOX distances (see Materials and Methods) in the best-fit model shown in Figure 3A.

^dNASNOX predicted average inter-R5 distances obtained from the pRNA tetramer crystal structure.⁴³

^eMajor population listed.