Clickbait? Ancient Kind: RNA part 2…

How can RNA from one branch of the tree of life be understood by organisms on another? 

It’s a common language, [Amy] Buck said. RNA has most likely been around since the very beginning of life. 

While organisms have evolved and diversified, their RNA-reading machinery has largely stayed the same. “RNA already has a meaning in every cell,” Buck said. “And it’s a pretty simple code.”

So simple, in fact, that a recipient cell can open and interpret the message before realizing it could be dangerous, the way we might instinctively click a link in an email before noticing the sender’s suspicious address. 

Indeed, earlier this year, [Hailing] Jin’s lab showed that Arabidopsis plant cells can send seemingly innocuous RNA instructions that have a surprise impact on an enemy fungus. 

In experiments, Jin’s team saw the Botrytis fungus read the invading mRNA along with its own molecules and unwittingly create proteins that damaged its infectious abilities.

It’s almost as if the plants were creating a “pseudo-virus,” Jin said —little packets of RNA that infect a cell and then use that cell’s machinery to churn out proteins.

“This is a pretty powerful mechanism,” she said. “One mRNA can be translated into many, many copies of proteins. … It’s much more effective than transporting the protein itself.”