RNA wins the Nobel Prize—again!

Last year, mRNA vaccines won the Nobel Prize in Physiology or Medicine. This morning found RNA once again the recipient of the Nobel Prize in Physiology or Medicine.

By the time I finished college, RNA was familiar to me as a family of biopolymers that together specified the manufacture of proteins in cells. Ribosomal RNA made up the platform and enzyme that performed the assembly of amino acids into proteins. Transfer RNAs were the small adapter molecules that brought each amino acid to the assembly plant. Messenger RNAs were the blueprint used to specify the order in which chains of amino acids were assembled into proteins. Importantly, the messenger RNAs in different cells dictated the properties of each cell, analogous to the combination of apps you’re running on your laptop dictates the tasks you can perform on it.

During my scientific career, I witnessed the discovery of how messenger RNA from a single gene can be cut up and the pieces pasted together in different combinations in different cells to give variant proteins from that single gene. We’ve learned a lot about how combinations of genes are activated to make their RNA—or not—as needed during development or in response to environmental conditions.

The 2024 Nobel is for the discovery of yet another type of RNA called microRNAs. MicroRNAs don’t encode any proteins. Instead, they bind to certain messenger RNAs and thereby regulate the amount of protein that can be made from those messenger RNAs. They can do this in two ways: (1) by programming the destruction of those messenger RNAs, or (2) by regulating the ability of those messenger RNAs to be used by the cells protein assembly plants.

The path to figuring out what microRNAs are doing involved basic research in the roundworm C. elegans, and a potent combination of genetics and biochemistry. The knowledge gained has yet to find widespread use in medicine, but as a fundamental breakthrough in human understanding of gene expression, this accomplishment certainly deserves the prize.