Longfin inshore squid (Doryteuthis pealeii) can make edits to their RNA in the cytoplasm, Science News reports. It adds that animals typically make RNA edits within the confines of the nucleus.
Researchers from the Marine Biological Laboratory found that the RNA editing enzyme ADAR2 is expressed outside of the nucleus in squid neurons. As they report in Nucleic Acids Research this week, they found by examining cytoplasm from nerve axons that ADAR2 was present there and that axon cytoplasm could catalyze RNA editing-related reactions. Additionally, a transcriptome-wide analysis found thousands of sites where RNA editing is more common along the axon than it is in the cell body.
"[W]e thought all the RNA editing happened in the nucleus, and then the modified messenger RNAs are exported out to the cell," senior author Joshua Rosenthal from MBL says in a statement. "Now we are showing that squid can modify the RNAs out in the periphery of the cell. That means, theoretically, they can modify protein function to meet the localized demands of the cell. That gives them a lot of latitude to tailor the genetic information, as needed."