An RNA Polymerase Uncovers New Information About the Origins of Life on Earth

How does life appear on earth? This has always been an unsolved mystery. According to the Physicists Organization Network, Canadian researchers published a report in the latest issue of Science that an RNA polymerase played an important role in the birth of life on earth. The new research provides new insights into the mystery of the origin of life on earth, and also helps scientists estimate the possibility of life being born on other planets.

A team led by Peter Unrau, professor of molecular biology and biochemistry at Simon Fraser University, has been committed to advancing the RNA world hypothesis to answer basic questions about the origin of life. This hypothesis suggests that life on earth begins with RNA molecules that can replicate themselves. These RNA molecules appeared before the evolution of deoxyribonucleic acid (DNA) and proteins, not only carrying genetic information, but also driving the chemical reactions necessary for the formation of life. DNA and protein now perform these two functions simultaneously in the human body.

In the latest research, Unrau's team conducted an in vitro evolution process in the laboratory and isolated a promoter-based RNA polymerase that can synthesize RNA using RNA as a template. A promoter is a DNA sequence that RNA polymerase recognizes, binds to, and initiates transcription.

Unrau said, "This RNA polymerase has many of the characteristics of modern protein polymerases. It can evolve to recognize RNA promoters and then copy RNA. Our findings mean that the same RNA polymerase that appeared early in the evolution of life may also exhibit such complex biological characteristics. "

There is evidence that RNA appears before DNA and protein. For example, ribosomes, the protein-making machinery in human cells, are made from RNA. In addition, DNA is also composed of RNA. Because RNA is a universal tool that can perform the functions of protein and DNA at the same time, this indicates that the DNA and protein that evolved later are an "upgrade" to enhance the cellular functions originally supported by RNA. The polymerase found in Unrau’s laboratory indicates that RNA replication may indeed exist in primitive life.

The long-term goal of the Unrau team is to build a self-evolving system in the laboratory. To do this, they need to create an RNA polymerase that can replicate itself to gain a deeper understanding of how early RNA life was formed. Unrau said, "By understanding the basic complexity of life in the laboratory, we can estimate the possibility of life appearing on other planets, and determine the possibility that planets such as Mars once existed or still exist."

For decades, the dominant life science theory has been the RNA world hypothesis. In other words, in the early stages of the origin of life, there was a molecular system composed entirely of RNA molecules. The information of the system is stored by RNA, and some RNA molecules with catalytic functions catalyze the transmission of RNA's own information and the self-replication of RNA molecules. This time, the researchers further refined the RNA world hypothesis and believed that the key to the origin of life on earth lies in RNA polymerase. This polymerase exhibits complex biological characteristics. The scientific research team is trying to create an RNA polymerase with similar functions that can build a microscopic world and observe the origin and evolution of life.