Table 1.

Experimental melting temperatures for self-complementary RNA duplexes in solutions of varying magnesium concentrations and in 1 M sodium chloride with no magnesium

RNA sequence (5′ to 3′)a	fGCb	Tmc (°C)
		0.5 mM Mg2+	1.5 mM Mg2+	3.0 mM Mg2+	10.0 mM Mg2+	1 M NaCld
CGCGCG	1.00	53.3	57.1	58.3	60.3	57.8
CGGCCG	1.00	58.2	61.2	63.6	64.9	63.2
GCGCGC	1.00	56.9	59.4	61.0	62.3	62.5
ACCGGU	0.67	52.3	55.6	56.8	58.4	53.9
AGCGCU	0.67	43.3	47.0	49.2	51.7	52.0
CACGUG	0.67	38.7	41.7	43.2	44.9	42.8
CAGCUG	0.67	37.9	40.8	42.4	44.7	43.1
CCAUGG	0.67	43.9	46.3	47.9	50.1	46.4
CCUAGG	0.67	48.4	51.4	52.3	54.2	50.0
CUGCAG	0.67	40.5	42.8	44.2	46.9	45.3
GACGUC	0.67	41.6	45.2	45.8	48.4	46.2
GAGCUC	0.67	41.4	44.5	46.7	48.5	48.7
GCAUGC	0.67	40.1	43.3	45.0	47.2	45.7
ACUUAAGU	0.25	32.1	35.9	38.5	40.0	40.3
AACUAGUU	0.25	38.8	42.0	43.4	45.8	45.7
ACUAUAGU	0.25	38.1	41.0	43.1	44.7	44.0
AGAUAUCU	0.25	34.9	37.8	40.0	43.1	41.4

^aAll oligonucleotides are forming self-complementary duplexes in solution.

^bf_GC is the fraction of G-C basepairs in the duplex.

^cCalculated for 0.1 mM oligonucleotide concentration based on the T_m⁻¹ versus ln C_T plots. Errors are typically ∼1.0°C for melting temperature measurements.

^dAll 1 M NaCl data are from Xia et al. (10), except for GCGCGC, which is from Chen and Znosko (13).