label: an adenosine in mRNA + S-adenosyl-L-methionine => an N(6)-methyladenosine in mRNA + S-adenosyl-L-homocysteine + H(+)
label_lc: an adenosine in mrna + s-adenosyl-l-methionine => an n(6)-methyladenosine in mrna + s-adenosyl-l-homocysteine + h(+)