Researchers published a study in the journal Cell on Friday. Until recently, it was believed that RNA could not survive for extended periods.
“Textbooks indicate that RNA is highly unstable and generally degrades within minutes of exiting a living cell,” remarked Marc Friedlaender, a computational biologist at Stockholm University and one of the study authors. “It’s truly remarkable that we discovered RNA dating back 40,000 years. No one thought this was feasible.”
This research may open up new avenues into historical understanding. Erez Eiden, a professor of biochemistry and molecular biology at the University of Texas Medical Branch, who was not involved in the study, noted that scientists will continue to refine the techniques used to analyze ancient RNA, similar to how they have done for years with ancient DNA.
Incorporating RNA analysis into the study of ancient genetics could fundamentally alter our perception of the biological history of the Earth, Eiden stated.
“We will be able to construct a more comprehensive and quantitative narrative of life’s history on our planet,” he added. “Suddenly, the Rosetta Stone appeared.…This is like an ancient hieroglyph of life.”
The discovery of RNA was facilitated by the find of Yuka in 2010, when members of the Yukagir community unearthed a mammoth in melting permafrost near the Arctic Ocean. Yuka was found resting on a cliff, partially mummified, and encased in a mat of strawberry blonde hair and flesh that remained pink until her discovery.
Paleontologists believe Yuka was pursued to death. Some evidence points to the creature being chased by a cave lion or possibly killed by modern humans. There are indications supporting both theories, with each species potentially playing a role in the extinction of this ancient animal.
In a world populated by cave lions, this creature experienced significant stress prior to its death.
Indeed, recent RNA analyses indicate that the profiled RNA displayed signs of physiological stress. The researchers utilized samples taken from the animal’s slow-twitch muscle fibers.
“We discovered that stress genes were activated,” Friedlander stated.
Provided by: Jens Olof Razin
Mammoths are not the only ancient species to have had their RNA analyzed. In 2019, researchers examined the RNA of 14,300-year-old wolf or dog pups.
RNA is synthesized from its DNA template through a process known as transcription. During transcription, certain genes are activated while others remain dormant.
This process is dynamic, and the genes expressed can fluctuate from day to night, according to Marmol Sanchez.
The researchers also identified a novel form of microRNA (a type of RNA governing gene expression) in mammoths that is unknown in modern elephants.
The RNA technology being developed may assist efforts to revive the woolly mammoth, as noted by Eiden, who is a member of the scientific advisory board for Colossal Biosciences, the company aiming to “resurrect” the woolly mammoth.
Professor Friedlander remarked that further research could also shed light on how some ancient viruses, which lack DNA, evolved over time.
“To understand the history of RNA viruses like SARS-CoV-2, we must detect these RNA molecules in historical and ancient samples to comprehend their evolution,” Friedlander explained.
Viruses such as Ebola, HIV, and influenza possess RNA genomes.
More research is required. In this study, the scientists investigated 10 mammoths but only obtained reliable RNA signals from three, including Yuka, the best-preserved specimen.
Since 2010, Yuka has been thought to be a female mammoth, but RNA and DNA analyses have revealed that she is, in fact, male.
Eiden highlighted that the RNA study underscores how little is understood about death and the varying rates of molecular breakdown after an organism’s demise.
“Our theories about what occurs to the physical matter of an organism post-mortem are still inadequate,” Eiden said. “What information is retained, and how legible can it remain over time? These are some intriguing questions.”
Source: www.nbcnews.com
