RNA: The cell’s central information carrier

Every cell in our body is a busy workplace where genetic information is continuously translated into action. Much of this happens through RNA – molecules that carry instructions from DNA to the cell’s protein machinery or serve a functional role in their own right. But in mammals like humans, most of the RNA produced is in fact non-functional. Only a small fraction – roughly 3 percent – serves a clear purpose. The rest is rapidly degraded.

“Cells produce enormous amounts of RNA, but only a tiny fraction has an actual function. Our task is to understand how they sort through it all,”
says Professor Torben Heick Jensen.

He continues: “How cells manage to distinguish between useful and redundant RNA – and avoid disrupting essential processes – is one of the central questions in modern molecular biology.”

A sea of transcription

During transcription – the process of RNA production – a vast number of short, unstable RNA molecules are generated. These often originate from the same starting points as the longer, functional RNAs. Up to 80 percent of RNA transcripts terminate prematurely and are degraded immediately. As a result, the functional RNAs that code for proteins or have other stable roles emerge amid a storm of transient, non-functional molecules.

To keep the system running smoothly, cells must rely on robust mechanisms to separate functional RNAs from non-functional ones – a kind of molecular quality control.

ARS2 – a molecular conductor

A key player in this quality control system is a protein called ARS2. Present on all newly transcribed RNA, ARS2 acts as a molecular gatekeeper, determining whether an RNA molecule should be processed and used, or marked for degradation. It interacts with either “productive” factors that promote RNA maturation and export, or with “destructive” factors that send the transcript to cellular decay machinery.

Torben Heick Jensen’s group has been a pioneer in mapping the cellular systems that guide ARS2’s decisions. In this project, the team will take the next step by examining how these mechanisms interact and evolve, especially as cells differentiate and take on new identities.

To do so, the researchers will deploy cutting-edge technologies – including tiCLIP, which tracks RNA-protein interactions down to single-nucleotide resolution in living cells – as well as advanced computational analyses and structural studies in collaboration with leading international partners.

Curiosity-driven research with far-reaching perspectives

Although the project is rooted in fundamental scientific curiosity, its findings may eventually have important applied potential. A better understanding of how cells regulate RNA production and degradation could pave the way for advances in biotechnology and medicine – for instance, by improving protein expression systems or enabling new therapeutic approaches based on RNA regulation.

As Torben Heick Jensen notes: “Our primary goal is to understand how the cell works. If we or others later find ways to use that knowledge commercially, that would be a phenomenal bonus.”

One of four Villum Investigators at the Faculty of Natural Sciences in 2025

The project will span six years and engage several PhD students, postdocs, and laboratory technicians. It will be carried out within the strong RNA research environment at Aarhus University.

To support the work, Torben Heick Jensen has been awarded a Villum Investigator Grant from the Villum Foundation, making him one of four researchers at AU’s Faculty of Natural Sciences to receive the prestigious funding in 2025. The grant is awarded to established researchers with bold ideas and a strong track record of scientific leadership.

Read the article by the Villum Foundation.

More information:
Prof. Torben Heick Jensen
Department of Molecular Biology and Genetics, Aarhus University
thj@mbg.au.dk