The Key to Immortality...Jellyfish!!!

    Turritopsis dohrnii, also known as The Immortal Jellyfish, is exactly the magical creature it sounds like. This little jelly is often found in temperate and tropical water such as the Mediterranean Sea. Like many other animals it has developed specialized survival techniques, in this case, immortality. When threatened, The Immortal Jellyfish is capable of reverting into its polyp form (literally reversing its age/physical development).  To be clear, there are other jellyfish with similar abilities. Multiple jellyfish species are capable of "rewinding" themselves. The Immortal Jellyfish, however, is the only one capable of doing so repeatedly and after entering the medusae phase of development.

    In Comparative Genomics of Mortal and Immortal Cnidarians Unveils Novel Keys Behind Rejuvenation, a research team attempts to uncover what specific genes give The Immortal Jellyfish its rejuvenation ability. This was done by comparing the Immortal Jellyfish's genome to Turritopsis rubra, its non-immortal cousin. Overall, their finding suggest that gene amplification, replication efficiency, DNA repair, and telomere activity are primary differences and potential contributors to increasing rejuvenation abilities. With further study, this research has the potential change the way we think of human aging. Maybe one day in the future the information we learn from The Immortal Jellyfish can be used to extend human life!

Researchers found a species of Jellyfish that are effectively immortal

In an article written by author Veronique Greenwood, she talks about how a small species of jellyfish known as Turritopsis dohrnii, that although these jellyfish swim and eat like many other jellyfish, they have a secret that sets them apart from other sea creatures. Turritopsis dohrnii live in the Mediterranean Sea and are secretly known to turn their old age back into their young selves. For Turritopsis dohrnii, when their bodies get damaged, the mature medusas can turn back time and transform themselves to their immature life stages. To do this, T. dohrnill sheds its limbs, allowing them to drift around in the water column and morph into a polyp form, which then allows them to attach themselves to rocks, plants or other sea life. After researching the jellyfish’s genome to search for the gene that controls this unusual life cycle, the only scientist, Shin Kubota at Kyoto University in Japan, found, after sequencing the genome, is that the jellyfish had extra copies of a particular gene. These additional genes allowed the researchers to see that these genes protect and repair the jellyfish’s DNA, which is an essential aspect of their survival. To test this rejuvenation process, the researchers put Turritopsis dohrnii under stressful conditions by not feeding them. The adult medusas shrank into smaller sizes, sprouted into polyps, and began remaking their adult bodies. During this process, the scientists captured snapshots of what genes the jellyfish were using in each stage of their development. In each phase, the scientists took jellyfish and froze them to turn them into mush to extract their mRNA, which gave them records of which genes were being used to make proteins. The scientists found that in the adults, their genes were relatively active, meaning they were used more frequently to make proteins. And as the jellyfish descended into the polyp phases, their genes became quieter, making less protein to form those smaller sizes.

I personally think that this type of science is so fascinating and could possibly help for future research for humans and for other living species. If jellyfish and humans have the same genes this could lead to a new era in medicine. Since researchers were able to figure out which genes were being used for each life stage, this could be a glimpse into future research of possible cancer treatments or other treatments of human health and medicine. 

Using Genetics to Better Understand Jellyfish's Neuron System

This article talks about how a group of researchers genetically modified Clytia hemisphaerica, a tiny jellyfish only about one centimeter when fully grown, using a genetic toolkit so that their neurons, when activated, individually glow with fluorescent light. And because the jellyfish is transparent, the researchers can watch the jellyfish's neuron activity. Unlike our brains, which is located in our head, the jellyfish's brain is spread out across their entire body almost like a net. Because of this, the jellyfish's different body parts can operate even when it is separated from the body. What the researchers wanted to find out is how decentralized nervous system can coordinate and operate behaviors. They tested their modified organism by looking at its feeding behavior.

When the Jellyfish eats a shrimp, it folds its body to bring the tentacle to its mouth while also bending its moth toward the tentacle at the same time. Examining the glowing neurons reveals that their is a surprising degree of organization. A subnetwork of neurons produces a particular neuropeptide is responsible for the inward folding of the body. The researchers hope to continue to use the genetically modified jellyfish to better understand how behavior is generated by whole neural systems. The researchers also noted that jellyfish are so distantly related to humans such as other model organisms like the mouse. In fact, worms are evolutionarily closer to humans than jellyfish. But the researchers say that because of their distance relationship with us is why they are important to study. They can be used to help us better understand the principles of neuroscience in nervous systems across all species and to discover useful biological innovations. Also, understanding these jellyfish nervous systems can be used as a springboard to understand more complex systems.

Jellyfish Development

This article by Okinawa Institute of Science and Technology (OIST) Graduate University explains the Genomic study reveals how jellyfish develop into floating beauties, rather than staying stationary like corals or sea anemones.