The Incredible Way This Jellyfish Goes Back in Time

at the second conference of the hydrazone society a paper was presented that was so revolutionary that members of the audience did not believe it could be true one attendee a respected marine biologist stated the observation from the paper was in fact totally impossible it was an observation made completely by mistake in the late 1980s two laboratory students collected a hydro-zone specimen that they believed to be turatopsis nutricula a tiny jellyfish less than a centimeter long the individuals they collected were in their immature adult medusae form meaning they were not sexually mature yet and unable to release eggs and sperm they placed the specimens in a tank hoping to breed them for research purposes and forgot all about them when they returned they expected to find sexually mature adults instead they found fewer adult medusas than when they started and lots of babies in the form of newly settled polyps on the bottom of the tank had these jellyfish reproduced that quickly and if they did what happened to all of the adults to find out the researchers started to keep a close watch on the individuals in the tank and what they found shocked them the adult meduse were not spawning and reproducing to create new baby polyps they were themselves reverting back into their juvenile form completely reversing the aging process what they had collected was not turatopsis nutricula but a different jellyfish turritopsis dornie eye one they realized is capable of benjamin buttoning itself over and over again to the point where scientists learned they had discovered something inconceivable immortality in a world obsessed with aging and mortality the media went crazy over this news what is this tiny jellyfish's secret to eternal youth can it really live forever and if it can how might we be able to harness this age reversing secret for ourselves to understand how teratopsis dornii achieves this amazing feat it's useful to look at its normal life cycle the immortal jellyfish is not a true jellyfish but a hydrozoon that spends most of its life in its hydroid stage but for our purposes we will refer to it by its commonly used jellyfish name the life cycle of this jellyfish starts when adult jellyfish in their recognizable medusae form swarm and release millions of eggs and sperm most species of jellyfish will swarm in the hundreds or even thousands for the purpose of reproducing when a sperm successfully fertilizes an egg the fertilized egg will grow into a planula a tiny floating larva within a day or two the planula will stick to a hard surface like the sea floor a rock or a coral once stuck they'll start the next phase the secured planula starts growing up from its perch forming a polyp this looks a bit like a plant a long stem with a bulbous head which now has a mouth and long waving fingers the polyp eats by sucking in food through its mouth using its tentacles to help grab it now the polyps turn into a production line creating a stack of cloned nearly jellyfish when the most mature clone is ready it's released and floats off into the water as a tiny version of a jellyfish called in a phyra now alone in the ocean all it has to do is eat and grow and eventually turn into the medusa we all recognize and that's the end of the line for most jellyfish they stay as a medusa swimming eating and spawning until they die but turatopsa's dornie eye has a nifty hack for getting around the slight inconvenience of death when this tiny jellyfish experiences high levels of stress starvation or physical damage it can send all of its cells back into a younger state the jellyfish shrinks and retracts its tentacles and the medusa turns into a blobby structure called a cyst that settles onto the ocean floor just like its past self within three days the blobby cyst starts growing into a polyp and the whole process starts over start to finish it can all be done in about a week it's like a butterfly turning back into a caterpillar and if that caterpillar could then break apart into multiple butterflies this amazing process has never actually been observed in the wild only in the lab but there's no reason to think it isn't going on throughout our oceans so what is going on how does an adult jelly turn back into a baby the immortal jellyfish can do this amazing rejuvenation through a process called cellular transdifferentiation this is when a cell of one type turns into an entirely different type of cell directly without turning into a neutral intermediate form first studies have shown that the medusa doesn't seem to contain stem cells a type of cell that has the potential to be turned into any kind of cell so it must be the case that its existing cells are repurposed scientists have found that the cells of the top layer of the dome shape of the medusa and the canal system basically the jellyfish's digestive system are the most likely to get turned into new cell types of course the cells that make up the dome of a medusa are different than the cells that make up a polyp they have different roles suited to different needs it's through trans differentiation that the immortal jellyfish can get these specialized medusa cells to turn into polyp cells this reversal of development goes against common ideas about aging across the animal kingdom it's long been believed that sexual maturation for any animal marks a point of no return that cells are stuck doing what they will always do until they reach senescence cell death but the immortal jelly can turn cells back into their earlier state at any point in their life cycle whether they're a newly produced medusa or an old timer on the verge of death all that's needed is a bit of shock in the first experiments proving this phenomenon a pinch with some tweezers was enough to get them to revert we still don't know exactly how teratopsis dornii does it but scientists have had a closer look at the cells of the cyst form of the immortal jellyfish and they found some interesting differences compared to its polyp state that could tell us how the immortal jellyfish prepares for its new life while in its cyst form turatopsa's dornii spends a good amount of its energy on internal upkeep in particular looking after its dna the jellyfish seems to be able to protect and repair its telomeres telomeres are strands of dna found at the end of chromosomes and a bit like the plastic bits on our shoelaces they protect the rest of our dna from damage especially during cell replication every time a cell replicates a little bit of dna is lost from the telomeres but because they are extremely long there is a lot to lose before any of the important dna is affected but eventually telomeres are ground down to nothing and dna is more prone to damage this leads to cell death and ultimately the death of an organism this is what happens in humans telomere shortening as it's known is a key element of aging but in turatopsis dornii cysts there seem to be a particularly high number of genes expressed that promote telomerase an enzyme that repairs telomeres with large amounts of this enzyme the immortal jellyfish could be protecting the cells from naturally aging by simply elongating the telomeres and protecting the jellyfish's dna on top of this when in its cysts stage the jellyfish spends little effort on replication or cell differentiation which makes sense it's actively trying to prevent cells from specializing the cysts also don't respond to external stimuli ensuring that they are focusing all of their energy on dna repair and maintenance until it's ready to become a polyp once more this has worked well for turritopsis dornii it's fast taking over the world's oceans originally from the mediterranean it's believed that they have hitchhiked on boats and are now found almost everywhere their resilience has probably helped contribute to their ability to survive across long distances and lots of environments researchers have found that in the lab a single turretopsis dornii is able to regenerate 10 times at intervals as short as one month in the wild this could go on for much longer possibly forever in an eternal loop of back and forth transdifferentiations it's unlikely that we'll ever be able to benjamin button ourselves but there are things we can learn from this jellyfish that could help us stave off some of the diseases that plague us later in life trans differentiation is an interesting field for scientists being able to turn one cell into another in few to no steps and over a short period of time could open the doors to treatments for things like parkinson's imagine if we could turn skin cells into neuronal cells to replace lost or damaged cells in the brain understanding how the immortal jellyfish does this could help us work out how to do it ourselves another area that the immortal jelly could shed light on is micro rnas these are short strands of genetic material that regulate our dna they can switch genes on and off and are involved in dna repair we know that a lot of dna repair is happening in a regenerating turretopsis dornii and finding out more about how micrornas act to regulate dna repair in the little jellies could help us do the same for our own cells having said that humans and jellyfish while pretty similar in terms of their dna when you consider how different we look still split apart on the tree of life some time ago and there are genes and jellyfish that aren't expressed in humans and vice versa so there may be some limitations to what is applicable even though terratopsis dornii was first discovered in 1883 we only found out it might be immortal in the 1980s and we're also learning that there may be other immortal creatures out there the natural world from organisms large and small from jellies to trees to microbes to fungi likely hold answers that we can't even conceive of right now but as we discover more biodiversity and as our scientific technology becomes increasingly sophisticated we are likely to find out more and it may mean new avenues for treatments for degenerative diseases and cancer while the immortal jellyfish may not hold the answer to a never-ending life for us it may at least give us a little longer to fill our increasingly long lives it's important to continuously fill our minds and if you're like me entertaining but educational documentaries are one of the best ways to fill both youtube can be a treasure trove of content and finding a bingeable channel or series that is also educational is one of the greatest feelings one of the worst feelings is when you're out of ideas of what to watch especially when you have your lunch sitting in front of you and you can't eat it until you find something good this happens to me when i've already seen nearly all the videos made by my favorite creators if you've ever felt this lack of content induced despair now is the best time ever to sign up to nebula the streaming platform me and several other educational content creators made together which is a gold mine of new original content to dive deep into history the brand new series battle of britain made by the team behind this channel and real engineering is of such high quality i can't believe it's not made for tv it's a series that will take you through the key moments of the first major military campaign fought entirely by air forces the 3d animations are out of this world and the storytelling will leave you captivated all while learning about one of the most important moments in modern history there are so many original series like this on nebula with more coming in all the time and right now is the single best time to sign up and with this subscription you are also supporting us in the best way possible every sign up helps us to hire more animators take on bigger projects and keep the lights on and the machines running so for something else to watch right now you can watch our previous video about the incredible harpy eagle or watch real engineering's latest 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Channel: Real Science

Views: 686,551

Keywords:

Id: DSLQYTt8BjA

Length: 14min 13sec (853 seconds)

Published: Sat May 21 2022

Reddit Comments

[u/Kerst_]

A 14 minutes and 40 seconds long video about how the medusa Turritopsis nutricula can reverse its life cycle.

[u/Varias279]

Propably our best bet without increasing chance cancer. 23 is coincidentally also when we are fully grown (prefrontal cortex).

https://www.reddit.com/r/longevity/comments/u4jom3/researchers_rejuvenate_skin_cells_of_53yearold/?utm_medium=android_app&utm_source=share

[u/CasinoBAMCO]

Wood was non degradable for a few millions of years, now life was not eternal for a few millions of years as well, untill that jellyfish appeared. 👽