Random Mutations Enable RNA Droplets to Mimic Primitive Cells

Scientists have shown that introducing a handful of random genetic changes can convert simple RNA condensates into structures that behave like rudimentary cells, complete with internal cavities, movement and the ability to capture external molecules.

The study builds on the growing understanding of biomolecular condensates—membraneless droplets formed when RNA and proteins separate from the surrounding solution. Such droplets are thought to have played a role in early biochemical organization before true cellular membranes evolved.

Researchers applied a random mutagenesis technique to short RNA sequences that normally form spherical droplets in vitro. After screening thousands of variants, a small subset displayed dramatic morphological shifts, developing hollow interiors and exhibiting dynamic, directed motion under microscopic observation.

Beyond shape changes, the mutated droplets demonstrated a capacity to sequester fluorescently labeled cargo particles, indicating that they can act as selective compartments. Their movement appeared powered by internal chemical gradients rather than external forces, a behavior reminiscent of primitive motility mechanisms.

The findings provide experimental support for hypotheses that simple nucleic acid polymers could have acquired cell‑like functions through incremental genetic variation, offering a plausible pathway toward the emergence of protocells.

Future work will aim to map the specific mutations responsible, test the robustness of the observed behaviors in more complex mixtures, and explore how such RNA‑based compartments might be engineered for synthetic biology applications such as targeted drug delivery or biochemical reactors.