Reverse Translation Discovered?
We will never look at life at quite the same way again.
Until now, information flow in biology looked like this:
DNA gets transcribed to RNA, wheich in turn is translated to protein. While reverse transcription does take place with retroviruses using reverse transcriptase, the central dogma of molecular biology held that proteins is an end product, and there is no information flow back from protein to nucleic acids.
This has just changed.
Today, a press release and a paper by a joint group of scientists at Franklin National Lab and NASA reveals a new RNA-Protein complex that can read short protein sequences and reverse-translate them back to RNA. The reverse-translation complex, which they call the emosobir (that’s “ribosme” in reverse) is larger even than the ribosome. This reverse translation activity has been initially observed in isolates of sludge-derived Amoeba lupicus from Lake Erie, but not published yet as the researchers wanted to duplicate the results in controlled lab conditions, which proved to be extremely challenging. Apparently reverse translation is due to the activity of a new kind of intracellular parasite. The Emosobir Containing Particle (ECP) resembles a giant virus. However, it is devoid of chromosomal DNA or RNA. Rather, it contains the ebosomir itself. Once the amoeba is infected, the capsid dissolves, and the protein is reverse-translated to RNA. From that point on, the amoeba’s cellular machinery is hijacked just like in a virus to translate the ECP mRNA to new ebosomir and ECP capsids. The process of reverse-translation and RNA-dependent RNA replication and translation is considerably slower than a viral infection — it can take 14-30 days for enough ECPs to accumulate to burst from an amoeba and infect another. The process is also quite inefficient, as it seems that in only 1% of the infected amoebas ongoing reverse translation is successful.
A Lattice of Ebosomirs in the infected Amoeba lupicus
The consequences of this finding are enormous. Although we are familiar with prions as replicating proteins without nucleic acids, and viroids as replicating nucleic acids without proteins, this is the first time that information flow from a protein to nucleic acids has been discovered.
The press conference will be held today at 4:00pm EDT. More details here: http://www.nasa.gov/
UPDATE: (April 2) too many people thought this was serious. Please check the date of this post. Then look up if there is even a Franklin National Lab or an A. lupicus. Then chill out.
Comments are closed.
