Table 1.

Melting temperatures of tC^O-containing RNA duplexes (T _mtC^O), the corresponding unmodified duplexes (T _m ^UM) and the difference in melting temperature as a result of changing one C for tC^O (ΔT _m).

Sequencea	Sequence name	T mtCO [°C]b	T m UM [°C]b	ΔT m [°C]
5′-CGCAUtC o AUCG-3′	UA	56	55	+1
5′-CGCAUtC o UUCG-3′	UU	57	56	+1
5′-CGCACtC o UUCG-3′	CU	68	63	+5
5′-CGCAGtC o GUCG-3′	GG	69	67	+2

^aIn unmodified sequences, tC^O is replaced by cytosine. ^bMeasurements were performed in PBS buffer (100 mM Na⁺, pH 7.5). T _m values were determined as the average of the temperature values at the maximum of the first derivative and at half maximum of the melting curves.