a 5-methylcytidine in RNA + S-adenosyl-L-homocysteine + H(+) => a cytidine in RNA + S-adenosyl-L-methionine
a 5-methylcytidine in rna + s-adenosyl-l-homocysteine + h(+) => a cytidine in rna + s-adenosyl-l-methionine