What powered the first life? RNA enzymes that produce GTP open the door to the "RNA World"

What Was the "Fuel" That Powered the Beginning of Life?

Life is not merely a collection of materials. It is a system equipped with mechanisms to absorb energy from the outside, maintain itself, inherit information, and gradually change. So, in the early stages of Earth, when there were no cells, protein enzymes, or complex metabolic pathways, what exactly did systems resembling life use as "fuel"?

Research addressing this question has been reported by a team at UC San Diego. The focus was on the "RNA World" hypothesis, which posits that RNA played a central role. In current life forms, DNA stores genetic information, proteins handle most chemical reactions, and RNA acts as a bridge. However, in the early stages of life, RNA might have been both an information molecule and a catalyst for chemical reactions.

Molecules where RNA acts as a catalyst are called "ribozymes." In this study, the researchers succeeded in enhancing the performance of a ribozyme that produces guanosine triphosphate, or GTP, one of the molecules necessary for extending RNA. GTP is an important energy and information-related molecule for modern organisms and also a material for RNA. If primitive RNA systems could supply GTP on their own, it would have been a significant advantage towards self-replication.

Why is GTP Important?

If RNA is likened to a sentence, GTP corresponds to one of the letters that make up that sentence. RNA is composed of units called nucleotides linked together. To connect these units into long chains, it is not enough for the materials to simply float in water. A chemical "pushing force" is needed to bind the units together.

In modern life, nucleoside triphosphates like ATP and GTP fulfill this role. As the name "triphosphate" suggests, they have multiple phosphate groups and use the energy from these bonds to drive reactions. To synthesize RNA, such activated components are necessary.

The problem is how such high-energy molecules could have been produced on Earth before the advent of life. Without protein enzymes, sophisticated metabolism like that of modern cells could not be used. At a stage where cell membranes, genes, and enzyme networks were incomplete, could RNA have had a mechanism to produce its own materials? This study shows that "at least in the laboratory, RNA catalysts can evolve in that direction."

Selecting "Well-Functioning Molecules" from 100 Trillion RNA Candidates

The research team created a massive molecular library with numerous mutations starting from an existing GTP-synthesizing ribozyme. The scale is said to be about 100 trillion types. This approach involves preparing an enormous number of RNA molecules with slight sequence differences and selecting the most efficient ones.

The selection process used emulsion technology, which disperses water droplets in oil. By enclosing RNA molecules in small water droplets, it becomes easier to distinguish how much GTP each molecule produces and how much that GTP contributes to RNA synthesis. It's akin to running countless tiny test tubes simultaneously.

Importantly, the design was not just to measure the ability to produce GTP but to link that GTP to RNA extension by RNA polymerase ribozyme. In other words, by "metabolically linking" GTP synthesis and RNA polymerization, the selection was conducted in a form closer to life-like functions.

As a result, the research team found a mutant with a significantly higher GTP turnover number than conventional types. According to the report, the most efficient mutant had 19 mutations and increased the GTP turnover number to about 13. The previous ribozyme had a turnover of about 1.7, so this is a significant improvement. In general articles, it is noted that the most productive ribozyme produced about 10 times more GTP than its precursor.

Not "Creating Life," but Reproducing "Part of a Life-Like Circuit"

It is important to note when reading this research that life was not created in the laboratory. What was demonstrated is a part of the linkage where a primitive RNA system produces energy molecules and uses those molecules to extend RNA chains. This is not a complete reproduction of the origin of life.

However, in the study of the origin of life, this "part" is extremely important. For life to begin, molecules carrying information need to be replicated. However, replication requires materials and energy. Even if there are materials, information will not increase if the reactions to connect them do not proceed. Conversely, even if there is energy, evolution will not begin without a mechanism to store information.

This achievement suggests the possibility that RNA can connect "reactions to produce its own materials" and "reactions to extend molecules similar to itself." This holds significant meaning when considering early life, where the boundaries between metabolism and genetics were not yet separated.

In modern cells, metabolism, genetics, membranes, and protein synthesis are intricately divided. However, at the beginning of life, such division likely did not exist. It is thought that a small number of molecules played multiple roles, and a network of chemical reactions that happened to connect well gradually became self-sustaining. Reconstructing that early stage in the laboratory is essential for concretely verifying the path to the origin of life.

Polyphosphate as a "Plausible Energy Source"

Another key to the research is polyphosphate. Polyphosphate is a molecule where phosphates are linked in a chain and is considered a candidate energy source that could have existed on primitive Earth. In this study, a polyphosphorylation reagent called cyclic trimetaphosphate is involved in the reaction to produce GTP from guanosine.

In the study of the origin of life, the question often arises, "Is it possible in the laboratory, but were the materials really present on primitive Earth?" With powerful modern reagents or overly artificial environments, chemical reactions can be advanced indefinitely. However, that does not explain the origin of life.

Therefore, attempts to link "plausible prebiotic energy sources" with RNA polymerization, as in this study, are meaningful. Of course, further examination is needed on where on primitive Earth, at what concentration, and how stable such molecules existed. Nevertheless, the idea that RNA can supply materials involved in its synthesis using energy derived from polyphosphate makes the RNA World hypothesis one step more concrete.

How Far Has the RNA World Hypothesis Progressed?

The RNA World hypothesis is intriguing, but many unresolved issues remain. RNA has been considered a strong candidate for early life because it can hold information and act as a catalyst. However, challenges remain, such as how to create RNA itself in prebiotic environments, how to stabilize RNA of sufficient length, how to suppress replication errors, and how to supply the energy needed for reactions.

This study delves into the challenges of "energy supply" and "linking RNA polymerization." With the improved performance of the GTP-synthesizing ribozyme, the possibility that RNA can play a role closer to supplying its own materials has become more realistic.

However, RNA is not completed with GTP alone. RNA requires multiple nucleotides corresponding to G, A, C, and U, and the improvement in GTP synthesis is just a part of the whole. Additionally, while the achievement of incorporating up to several guanosines into an RNA polymer is significant, it is still far from creating a long, self-replicating RNA genome. Therefore, this research is more accurately seen as "one of the necessary components for the origin of life has been experimentally strengthened" rather than "conclusive evidence of the origin of life."

Quiet Sharing Among Specialists on Social Media

The reaction to this research on social media is currently centered more on quiet sharing by highly specialized communities and science news accounts rather than explosive dissemination.

In the Reddit astrobiology community, the UC San Diego article was posted as "Research." However, as far as could be confirmed, there was little notable discussion in the comments section, with guidance from automated moderators being predominant. This indicates that the topic is not of low value but rather that the content is quite specialized and difficult for general users to immediately engage in discussion.

On LinkedIn, San Diego Biotech Networks introduced this research and shared the key point that an early biological system capable of producing GTP would be advantageous for self-replication. Here too, the introduction was more as a biotech and life sciences news piece rather than eliciting emotional reactions.

On X, it has been confirmed that astrobiology-related accounts and users are sharing the article. The focus of the reaction is on the question "What powered the earliest life on Earth?" itself, reaching those interested in keywords such as the origin of life, astrobiology, and the RNA World.

Overall, the atmosphere on social media is not at the stage of public excitement over a "great discovery," but rather a more specialized reception as "an important piece of the puzzle in origin of life research." While it is a theme that can easily be given a flashy headline, the actual achievement is very precise and incremental. Therefore, when conveying the research content, it is more honest to express it as "examining how close an RNA-only world can get to self-sustainability" rather than overly hyping "creating life."

Why This Research Also Relates to Astrobiology

Research on the origin of life is not just a discipline to understand Earth's past. If we understand the conditions under which life could begin, it changes the perspective when searching for life on Mars, Europa, Enceladus, or distant exoplanets.

Life requires not only water, carbon, and organic molecules but also a flow of energy to drive reactions. What kind of environment and molecules connect the replication of information with metabolism? If those conditions become clear, the "chemical reactions to look for" when searching for life in the universe also become clearer.

This research, as a laboratory model of the RNA World, connected the relationship between energy sources, catalysts, and RNA synthesis. This is also useful for considering the conditions under which life-like chemistry might begin in places other than Earth. For example, in celestial bodies with subsurface oceans or environments where energy gradients arise on mineral surfaces, what molecules might participate in self-replicating reaction networks? This provides an experimental basis for such questions.

Life Did Not Originate All at Once

When we use the term "origin of life," we tend to imagine that non-living matter transformed into living organisms in an instant. However, it is likely that the boundary between life and non-life was continuous. Initially, it was merely a chemical reaction that absorbed energy from the environment, gathered materials, increased similar molecules, and underwent mutation and selection. Somewhere in that process, the properties we call life emerged.

This ribozyme research captures a scene from that continuous process. Producing GTP. Extending RNA. Selecting molecules that work better. All these are phenomena that can be considered pre-evolutionary stages. They are not yet cells. They are not yet organisms. Still, there is a budding of life-likeness.

In the shallow pools of primitive Earth, volcanic activity, mineral surfaces, cycles of drying and wetting, ultraviolet rays, lightning, and hydrothermal environments, countless chemical reactions must have been tested. Among them, if reactions that happened to connect information and energy stabilized, were selected, and became more complex, this research can be seen as an attempt to recreate that "connection" in the laboratory.

Not Flashy, But a Profound Advance

This achievement is somewhat difficult to convey to the general public. It lacks the intuitive impact of a new dinosaur fossil or a candidate trace of life on Mars. However, it is fundamentally important when considering the origin of life.

For life to begin, not only did information molecules need to be replicated, but an energy system to support that replication was necessary. This study demonstrated the flow where RNA catalysts supply GTP, and that GTP is used for RNA polymerization. Moreover, it showed that performance can be enhanced through mutation and selection. This reaffirms that the RNA World is not just a hypothesis but a subject that can be gradually verified through experimentation.

Of course, the complete picture of the origin of life is still distant. Many challenges remain, such as nucleotides other than GTP, the stability of RNA sequences, the relationship with membrane structures, the realism of environmental conditions, and the completion of self-replicating systems. Nevertheless, this research has strengthened the part of the "engine" of early life.

The beginning of life may not have been a mysterious one-time miracle but an accumulation of chemical reactions. Small RNA molecules receive energy and gradually extend molecules similar to themselves. Considering that this slight advance became the starting point for billions of years of evolution, the improvement of the ribozyme in this study holds a quiet yet grand significance.

In our cells today, molecules like GTP and ATP are constantly at work. Some of the molecules driving modern life may harbor ancient memories from the chemical world before life. This research is an attempt to trace those memories in the laboratory and provides another concrete clue to the question, "Where did life come from?"

Source URL

Refer to the Phys.org article for a general explanation of the research overview, GTP-synthesizing ribozyme, approximately 100 trillion types of mutant ribozymes, and about tenfold improvement in GTP production efficiency.
https://phys.org/news/2026-06-powered-earth-earliest-life.html

Refer to the UC San Diego Today article for information on the research team, announcement date, authors, funding by NASA ICAR, and comments from Ulrich Müller.
https://today.ucsd.edu/story/what-powered-the-earths-earliest-life

PNAS paper "A GTP synthase ribozyme with increased GTP turnover." Refer to the paper title, DOI, and primary information on the research content.
https://www.pnas.org/doi/10.1073/pnas.2520997123

Refer to PubMed for information on the journal volume, authors, abstract, GTR1 turnover, efficient mutant with 19 mutations, and guanosine incorporation into RNA polymer.
https://pubmed.ncbi.nlm.nih.gov/42263123/

Reddit r/Astrobiology post. Refer to the sharing of the research article as "Research" and the limited discussion observed within the scope of confirmation as a reaction from SNS and community.
https://www.reddit.com/r/Astrobiology/comments/1u52yq7/what_powered_the_earths_earliest_life/

LinkedIn's San Diego Biotech Networks post. Refer to the sharing status on biotech-related SNS.
https://www.linkedin.com/posts/san-diego-biotechnology-network_what-powered-the-earths-earliest-life-activity-7470508049523310592-u7Wf

Astrobiology.com article. Refer to the reposting and sharing status in astrobiology-related media.
https://astrobiology.com/2026/06/what-powered-the-earth