Cells From Different Species Can Exchange ‘Text Messages’ Using RNA

The archetypal version of this story appeared in Quanta Magazine.

For a molecule of RNA, the satellite is simply a unsafe place. Unlike DNA, which tin persist for millions of years successful its remarkably stable, double-stranded form, RNA isn’t built to last—not adjacent wrong the compartment that made it. Unless it’s protectively tethered to a larger molecule, RNA tin degrade successful minutes or less. And extracurricular a cell? Forget astir it. Voracious, RNA-destroying enzymes are everywhere, secreted by each forms of beingness arsenic a defence against viruses that spell retired their familial individuality successful RNA code.

There is 1 mode RNA tin past extracurricular a compartment unscathed: successful a tiny, protective bubble. For decades, researchers person noticed cells releasing these bubbles of compartment membrane, called extracellular vesicles (EVs), packed with degraded RNA, proteins, and different molecules. But these sacs were considered small much than trash bags that whisk broken-down molecular junk retired of a compartment during regular decluttering.

Then, successful the aboriginal 2000s, experiments led by Hadi Valadi, a molecular biologist astatine the University of Gothenburg, revealed that the RNA wrong immoderate EVs didn’t look similar trash. The cocktail of RNA sequences was considerably antithetic from those recovered wrong the cell, and these sequences were intact and functional. When Valadi’s squad exposed quality cells to EVs from rodent cells, they were shocked to observe the quality cells instrumentality successful the RNA messages and “read” them to make functional proteins they different wouldn’t person been capable to make.

Valadi concluded that cells were packaging strands of RNA into the vesicles specifically to pass with 1 another. “If I person been extracurricular and spot that it’s raining,” helium said, “I tin archer you: If you spell out, instrumentality an umbrella with you.” In a akin way, helium suggested, a compartment could pass its neighbors astir vulnerability to a pathogen oregon noxious chemic earlier they encountered the information themselves.

Since then, a wealthiness of grounds has emerged supporting this theory, enabled by improvements successful sequencing exertion that let scientists to observe and decode progressively tiny RNA segments. Since Valadi published his experiments, different researchers person besides seen EVs filled with analyzable RNA combinations. These RNA sequences tin incorporate elaborate accusation astir the compartment that authored them and trigger circumstantial effects successful recipient cells. The findings person led immoderate researchers to suggest that RNA whitethorn beryllium a molecular lingua franca that transcends accepted taxonomic boundaries and tin truthful encode messages that stay intelligible crossed the histrion of life.

In 2024, caller studies person exposed further layers of this story, showing, for example, that on with bacteria and eukaryotic cells, archaea besides exchange vesicle-bound RNA, which confirms that the improvement is cosmopolitan to each 3 domains of life. Another survey has expanded our knowing of cross-kingdom cellular connection by showing that plants and infecting fungi tin use packets of havoc-wreaking RNA arsenic a signifier of coevolutionary accusation warfare: An force compartment reads the RNA and builds self-harming proteins with its ain molecular machinery.

“I’ve been successful awe of what RNA tin do,” said Amy Buck, an RNA biologist astatine the University of Edinburgh who was not progressive with the caller research. For her, knowing RNA arsenic a means of connection “goes beyond appreciating the sophistication and the dynamic quality of RNA wrong the cell.” Transmitting accusation beyond the compartment whitethorn beryllium 1 of its innate roles.

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The microbiologist Susanne Erdmann studies viral infections successful Haloferax volcanii, a single-celled organism that thrives successful unbelievably salty environments specified arsenic the Dead Sea oregon the Great Salt Lake. Single-celled bacteria are known to speech EVs widely, but H. volcanii is not a bacterium—it’s an archaean, a subordinate of the 3rd evolutionary subdivision of life, which features cells built otherwise from bacteria oregon eukaryotes similar us.

Because EVs are the aforesaid size and density arsenic the microorganism particles Erdmann’s squad studies astatine the Max Planck Institute for Marine Microbiology successful Germany, they “always popular up erstwhile you isolate and purify viruses,” she said. Eventually, her radical got funny and decided to peek astatine what’s inside.