How Cephalopods Modify Their RNA

Soft-bodied cephalopod's main source of RNA editing is known as adenosine to inosine (A-to-I) editing. A-to-I editing happens when the enzyme ADAR2 takes one nitrogen and two hydrogen atoms from adenosine which turns it into inosine. Inosine is read as guanine by ribosomes which can change the amino acid into something other than what it used to be if there was still an adenine. This type of RNA editing is known as RNA recoding. Mollusks, humans, and other mammals do not seem to do it to the same extent. For example, Rosenthal, Eisenberg, and colleagues reported that longfin squid have 57,108 recoding sites. Multiple species of octopus, squid, and cuttlefish had been examined and each had tens of thousands of recoding sites. Coleoids have these many opportunities to recode because of their ADAR2 enzyme can be found in the cytoplasm.