4XK0

Crystal structure of a tetramolecular RNA G-quadruplex in potassium

Experimental procedure

Experimental method	SINGLE WAVELENGTH
Source type	SYNCHROTRON
Source details	ALS BEAMLINE 5.0.2
Synchrotron site	ALS
Beamline	5.0.2
Temperature [K]	100
Detector technology	CCD
Collection date	2014-08-26
Detector	ADSC QUANTUM 315r
Wavelength(s)	0.8266
Spacegroup name	P 4 21 2
Unit cell lengths	33.133, 33.133, 54.843
Unit cell angles	90.00, 90.00, 90.00

Refinement procedure

Resolution	21.540 - 1.080
Rwork	0.144
R-free	0.14400
Structure solution method	SAD
Data scaling software	HKL-2000
Phasing software	SHELX
Refinement software	PHENIX

Data quality characteristics

	Overall	Inner shell	Outer shell
Low resolution limit [Å]	50.000	50.000	1.090
High resolution limit [Å]	1.070	2.900	1.070
Rmerge	0.112	0.128	0.187
Rmeas	0.117	0.135	0.198
Rpim	0.034	0.041	0.061
Total number of observations	310744
Number of reflections	25610
<I/σ(I)>	31.8
Completeness [%]	97.4	95.5	53.5
Redundancy	12.1	11.3	9.4
CC(1/2)		0.982	0.981

Crystallization Conditions

crystal ID	method	pH	temperature	details
1	VAPOR DIFFUSION, HANGING DROP	6	294	40 mM potassium cacodylic acid (pH 6.0), 35% 2-methyl-2,4-pentanediol, 5 mM spermine hydrochloride, 80 mM potassium chloride, 0.5 mM DHX36 fragment, 20 mM barium chloride