RNA recovered from extinct species for the first time

In a groundbreaking study published in the journal Genome Research on September 20, 2023, scientists announced that they had successfully recovered RNA from an extinct species for the first time. The RNA, which was extracted from the skin and muscle of a 130-year-old Tasmanian tiger specimen, is the oldest RNA ever sequenced.

RNA is a single-stranded molecule that plays a vital role in all living cells. It is responsible for carrying genetic information from DNA to proteins, and it also regulates many other cellular processes. However, RNA is much more fragile than DNA, and it breaks down quickly after death. As a result, it was previously thought that it would be impossible to recover RNA from extinct species.

The researchers who conducted the study used a new technique called "RNA capture sequencing" to extract and sequence the RNA from the Tasmanian tiger specimen. RNA capture sequencing involves using short DNA probes to bind to specific RNA sequences. The probes are then attached to magnetic beads, which are used to isolate the RNA from the rest of the sample. The RNA can then be sequenced using standard methods.

The researchers were able to recover and sequence RNA from over 100 genes in the Tasmanian tiger specimen. This allowed them to reconstruct the transcriptome, which is the complete set of RNA molecules expressed by a cell or tissue. The researchers also found that the RNA was well-preserved, and they were able to identify muscle- and skin-specific protein-coding RNAs, as well as microRNAs, which are small RNAs that regulate gene expression.

The recovery of RNA from an extinct species is a major breakthrough in paleogenomics. It opens up the possibility of studying the gene expression and regulatory mechanisms of extinct species, something that was previously impossible. This new knowledge could be used to better understand the evolution of species and the factors that contribute to extinction.

In addition, the recovery of RNA from an extinct species could have implications for conservation efforts. For example, researchers could use the RNA to identify genes that are important for survival in certain environments. This information could then be used to develop strategies for protecting endangered species.

The researchers who conducted the study say that they are hopeful that their new technique will be used to recover RNA from other extinct species in the future. They are particularly interested in recovering RNA from woolly mammoths and other ancient animals that have been preserved in permafrost.

Implications

The recovery of RNA from an extinct species is a significant advance in paleogenomics, and it has a number of potential implications for research and conservation.

One of the most immediate implications is that it will allow scientists to study the gene expression and regulatory mechanisms of extinct species. This was previously impossible, as RNA degrades quickly after death. By studying the RNA of extinct species, scientists can learn more about their biology, evolution, and how they responded to environmental changes.

For example, the researchers who conducted the study were able to identify muscle- and skin-specific protein-coding RNAs, as well as microRNAs, in the Tasmanian tiger specimen. This information could be used to learn more about how the Tasmanian tiger's muscles and skin functioned, and how they were regulated.

The recovery of RNA from extinct species could also have implications for conservation efforts. For example, researchers could use the RNA to identify genes that are important for survival in certain environments. This information could then be used to develop strategies for protecting endangered species.

For example, if researchers could identify genes that are important for drought tolerance in extinct species, they could use this information to develop breeding programs for endangered species that are threatened by drought.

The recovery of RNA from extinct species also has the potential to revolutionize the field of de-extinction. De-extinction is the process of bringing back extinct species to life. While de-extinction is still a long way off, the recovery of RNA from extinct species is a significant step in the right direction.

If researchers can develop a way to repair and synthesize ancient RNA, they could potentially use it to create viable embryos of extinct species. These embryos could then be implanted in surrogate mothers or grown in artificial wombs.

Of course, there are a number of ethical and practical challenges that would need to be addressed before de-extinction could become a reality. However, the recovery of RNA from extinct species is a major step towards making de-extinction a possibility.

Challenges and future directions

While the recovery of RNA from an extinct species is a major breakthrough, there are still a number of challenges that need to be addressed before this technique can be widely used.

One challenge is that the RNA from extinct species is often very degraded. This means that it can be difficult to extract and sequence the RNA without damaging it. Researchers are working on developing new techniques to extract and sequence RNA from ancient samples, but there is still room for improvement.

Another challenge is that it can be difficult to distinguish between RNA from the extinct.