Scientists have made an exciting discovery: they recovered ancient RNA from a young mammoth named Yuka that lived around 40,000 years ago in what we now call Siberia. This remarkable find helps us understand what the mammoth experienced just before its death.
Researchers extracted the RNA from well-preserved mummified leg tissue, making it the oldest RNA ever sequenced. By studying it, they aim to discover which genes were active in Yuka’s cells at the end of its life.
Love Dalén, an expert in evolutionary genomics, explains that all cells contain the same DNA, but RNA plays a crucial role in determining how those genes express themselves. It’s all about which genes are turned on or off in different cells. This insight transforms our understanding of the mammoth’s biology just before it perished.
While DNA can last for over a million years, RNA was once thought to be too fragile to survive long periods. This breakthrough suggests that RNA might hold more secrets about the past, especially if techniques continue to improve.
During their research, scientists examined ten frozen mammoth samples. Only three yielded RNA fragments, with Yuka’s sample providing enough data to understand its biological state at the time of death. They identified messenger RNA, which codes for proteins, and microRNA, which regulates gene activity. This indicates that Yuka might have been near death, as shown by the metabolic changes in its muscles.
Interestingly, the study found that the mammoth had mostly slow-twitch muscle fibers active at the time of death. This discovery supports the idea that the mammoth was likely making final movements before it died. The proteins linked to muscle function, like titin and nebulin, were also detected in the tissue.
Marc Friedländer, another researcher, noted that finding specific microRNAs in ancient samples is groundbreaking. These findings open doors to understanding gene regulation in extinct species, a concept backed by Erez Lieberman Aiden, a biochemist who sees the study as significant and impressive.
Dalén believes these methods could lead to significant advancements in research, including exploring the evolution of ancient viruses, many of which exist only in RNA form. This could also aid in efforts to bring back extinct species through genetic editing, such as the woolly mammoth, dodo, and Tasmanian tiger.
Although Yuka’s RNA is the oldest yet recovered, it’s not the first instance of ancient RNA being sequenced. Recent studies have also found RNA from a 130-year-old Tasmanian tiger and a 14,300-year-old wolf. This growing body of evidence suggests that RNA might become a valuable source of information about extinct organisms.
However, Aiden cautions that while this study is a significant step forward, it’s still early to determine if RNA will serve as a major resource for understanding extinct life, much like DNA has.
This ongoing research reminds us that we are still uncovering the mysteries of the ancient world, one discovery at a time. For more fascinating insights into science, you can check reliable sources like Cell and recent articles on RNA studies.
