RNA may have been able to support life on its own, according to a new discovery that could shed light on the origins of life on Earth. The great question of how Earth evolved from a barren world to our current one, swarming with life, may have been answered by researchers from the Georgia Institute of Technology.
In our modern world, cells contain both DNA and RNA. The RNA is controlled by a complex interplay between itself, DNA and enzymes. This has led some scientists to doubt whether RNA could have survived on its own, without accompanying nucleic acids and protein-based enzymes. Now it appears that RNA may have been existed on its own, before the development of DNA.
The research involved re-making the conditions that existed on Earth three billion years ago in a laboratory. At that time, the Earth was nearly devoid of oxygen and rich with iron. When researchers placed RNA within the chamber, some segments of the code, once inactive, came back to life.
Loren Williams, a professor at GIT said, "[O]ur experiments may have revived a latent function of RNA."
Last year, the team had postulated that iron atoms back then, in the oxygen-free environment, could perform single-electron transfer, the role that magnesium plays today in catalyzing the reactions necessary for photosynthesis and respiration.
Loren Williams, a Georgia Tech biochemist said, "Our study shows that when RNA teams up with iron in an oxygen-free environment, RNA displays the powerful ability to catalyze single electron transfer, a process involved in the most sophisticated biochemistry, yet previously uncharacterized for RNA."
The debate over whether or not RNA could survive on its own has been raging for years. One well-known proponent of the RNA-first theory was Francis Crick, who co-discovered the structure of DNA in 1953, in conjunction with James Watson.
Ribosomes, a variety of RNA discovered in the 1980's, acts like an enzyme, making reactions easier within cells. It was previously believed that only proteins could perform the required cellular functions.
Future research by the team will center on whether other metals common on Earth in the earliest days of life could have also played roles in RNA processes that could shed light on the earliest days of life on Earth.
