Key facts
- Researchers have created artificial cells, named SpudCells, capable of self-division.
- These SpudCells can import nutrients and replicate their genetic material.
- The system relies on viral proteins and externally supplied translation machinery.
- SpudCells can undergo several generations of division before genetic material is lost.
- The research provides a model for studying the origin of life and minimal cellular functions.
Researchers at the University of Minnesota have developed artificial cells, termed SpudCells, that can perform a few rounds of cell division. These SpudCells are designed to enclose genetic material and continuously import necessary materials from their environment, addressing a key challenge in understanding the origin of life.
The system utilizes genetic components derived from viruses. For instance, the DNA replication mechanism is adapted from the Phi29 bacteriophage, and the RNA production system is based on the T7 virus. The translation machinery, responsible for converting RNA into proteins, was supplied externally by purifying the necessary proteins. The SpudCells' genome consists of approximately 90,000 bases spread across seven circular DNA molecules.
A significant limitation is the random distribution of these DNA molecules during division, leading to the loss of genetic material over successive generations. The SpudCells did not survive beyond five generations due to this issue. To facilitate feeding, the cells were engineered with a gene for a pore protein, allowing small molecules and ions to diffuse in. Larger components, like the translation machinery, were delivered through membrane fusion, a process facilitated by a tagged pore protein.
Cell division was initially induced mechanically but later achieved by adding chemicals that caused pore proteins to clump, leading to membrane budding. This process, though random, approximates cell division. The researchers demonstrated that natural selection could operate on these artificial cells by altering the pore protein levels, leading to faster growth in nutrient-limited conditions.
While the SpudCells are highly engineered and not a direct replica of early life, they offer a valuable analog for studying the origin of life and exploring minimalistic cellular systems. Future research could focus on improving genetic material distribution during division and developing more sophisticated pore proteins.