label: uridine in 25S rRNA + S-adenosyl-L-methionine <=> N(3)-methyluridine in 25S rRNA + S-adenosyl-L-homocysteine + H(+)
label_lc: uridine in 25s rrna + s-adenosyl-l-methionine <=> n(3)-methyluridine in 25s rrna + s-adenosyl-l-homocysteine + h(+)