14 DAY TRIAL // Decades ago, researchers discovered that ribonucleic acid (RNA) can act as a catalyst for certain chemical reactions in the cell. This led to a train of thought that ultimately showed the molecule to precede more-complex DNA by eons. Now, experts want to build a cell to prove this is true.
Howard Hughes Medical Institute (HHMI) investigator Jack Szostak, PhD, who is also based at the Harvard University, has been leading his team in such an endeavor for a very long time, and the collaboration is finally making headway.
What the researchers want to do is create a simple cell, capable of surviving based on processes studies hypothesize were sufficient to support the development of early life. Central to this work is the idea that RNA does more in the cell than simply store genetic data needed for protein construction.
One of the most important traits that separates this compound from DNA or proteins is the fact that it could be able to catalyze its own replication, something that the other molecules cannot do. However, this has not been clearly established as of yet, Daily Galaxy reports.
The 1980s discovery that RNA may be able to recreate itself “inspired me to try to think of ways to make RNAs in the lab that could catalyze their own replication,” Szostak explains. He and his team are currently building simple structures in test tubes. These constructs resemble simple cells.
One of the most promising avenues of research is montmorillonite, a clay mixture that geologists established was very common on early Earth. This material was also demonstrated to be capable of catalyzing the chemical reactions needed to put RNA together.
“It's exciting because we know that a particular clay mineral helps with the assembly of RNA. There certainly would have been lots of environments on early Earth with clay minerals. It's something that forms relatively easily as rocks weather,” Szostak explains.
What this work does is basically propose an inorganic origin for life. The earliest organisms that could be classified as living may have arisen from nonliving molecules. There is however no way of knowing for sure what actually happened billions of years ago.
This line of inquiry is made very difficult by the fact that no fossils remain of these early creatures. If experts were to find the remnants of an organism that lived 3.8 billion years ago or before, then this issue could be settled within a matter of months.