The Structure and Nonfunction of RNA

An artist's rendering of a Ribonucleic Acid (RNA) molecule.

Credit: Nicolle Rager Fuller, National Science Foundation

An artist’s rendering of a Ribonucleic Acid (RNA) molecule.

Credit: Nicolle Rager Fuller, National Science Foundation

By studying how the structural components of RNA interact, and how the molecule performs the remarkable feat of self-assembling, scientists have uncovered new details about the chemical evolution of RNA.

Ribonucleic acid (RNA) exist in every living cells and plays numerous roles in living organisms. It’s most well-known duties are to help transport information and to participate in regulating how and when genes are expressed. RNA is believed to be one of the key molecules necessary for life as we know it.


The “RNA World” Hypothesis – Jack Szostak (Harvard/HHMI) Credit: iBioEducation(YouTube)
Previous studies have shown that RNA is an ancient molecule, and may have been present on Earth as long as life itself. Because of this, scientists have long wondered if RNA played a role in life’s origins on our planet. This is the basis for the theory of the ‘RNA world.’ In this proposed scenario, RNA would have functioned not only as a carrier of information in cells, but also as a catalyst for the reactions that keep cells alive.

Ramanarayanan Krishnamurthy. Associate Professor of Chemistry at the The Scripps Research Institute. Credit: The Scripps Research Institute

Lead author Ramanarayanan Krishnamurthy of the Department of Chemistry at Scripps Research Institute. Credit: The Scripps Research Institute

In recent decades, many studies have shown that RNA can perform a number of additional functions in cells. Studying the details of RNA’s structure and how it assembles can help shed light on whether or not its role in cellular reactions has changed over time.

There are many nuances in how structural components of RNA ultimately assemble into a molecule. The ways in which they assemble determine whether or not the molecule is capable of participating in certain reactions. Sometimes, the molecule assembles in such a way that it is rendered useless, or nonfuctional. These nonfunctional RNA molecules are what the research team turned to for their study. By comparing nonfunctional RNA molecules to functional ones, scientists were able to uncover new clues about how RNA molecules could have evolved over time at the chemical level.

The study, “RNA as an Emergent Entity: An Understanding Gained Through Studying its Nonfunctional Alternatives,” was supported by the National Science Foundation (NSF) and the NASA Astrobiology Program under the NSF/NASA Center for Chemical Evolution.