Immortal Animals

[PlutonianEmpire]

http://green.yahoo.com/blog/guest_bl...al-animal.html

The turritopsis nutricula species of jellyfish may be the only animal in the world to have truly discovered the fountain of youth.

Since it is capable of cycling from a mature adult stage to an immature polyp stage and back again, there may be no natural limit to its life span. Scientists say the hydrozoan jellyfish is the only known animal that can repeatedly turn back the hands of time and revert to its polyp state (its first stage of life).

The key lies in a process called transdifferentiation, where one type of cell is transformed into another type of cell. Some animals can undergo limited transdifferentiation and regenerate organs, such as salamanders, which can regrow limbs. Turritopsi nutricula, on the other hand, can regenerate its entire body over and over again. Researchers are studying the jellyfish to discover how it is able to reverse its aging process.

Because they are able to bypass death, the number of individuals is spiking. They're now found in oceans around the globe rather than just in their native Caribbean waters. "We are looking at a worldwide silent invasion," says Dr. Maria Miglietta of the Smithsonian Tropical Marine Institute.

[peter grimes]

Fascinating. Transdifferentiation seems like alchemy! The array of strategies found in the biosphere is truly staggering.

OT: @PlutonianEmpire - why do you advocate real life nuclear war? I advocate reducing US stockpiles (to the 100's or so). I'm open to hearing your side of the argument

[GoodGame]

Interesting. But I wonder if it can solve the "end-replication problem" infinitely, at well.

I suppose it could if it could, short of environmental mutagens, if it could stock up on some cells that didn't reproduce, and therefore didn't experience shortening telomeres. Sort of a way to "bank" the organisms genome to reseed the genome of differentiating cells.

[PlutonianEmpire]

Originally Posted by peter grimes

Fascinating. Transdifferentiation seems like alchemy! The array of strategies found in the biosphere is truly staggering.

OT: @PlutonianEmpire - why do you advocate real life nuclear war? I advocate reducing US stockpiles (to the 100's or so). I'm open to hearing your side of the argument

I don't wanna deviate from the OP too much, so I'll just put my response in spoilers.

Spoiler:

"Advocate" is probably the wrong word. Simply put, there is no sane argument for nuclear war. I want nuclear war because a) i like large explosions, and b) I think the world would be better off if humans went extinct, although there's probably better ways for species suicide than nuking each other and taking everything else with it.

Originally Posted by GoodGame

Interesting. But I wonder if it can solve the "end-replication problem" infinitely, at well.

tl;dr. Could someone summarize it, please?

[GoodGame]

Originally Posted by PlutonianEmpire

I don't wanna deviate from the OP too much, so I'll just put my response in spoilers.

Spoiler:

"Advocate" is probably the wrong word. Simply put, there is no sane argument for nuclear war. I want nuclear war because a) i like large explosions, and b) I think the world would be better off if humans went extinct, although there's probably better ways for species suicide than nuking each other and taking everything else with it.

tl;dr. Could someone summarize it, please?

Super simply, as DNA is replicated, there's an issue with replicator enzyme (DNA polymerase) needing a primer to latch onto. When DNA is replicated, one strand is the template and is replicated continuously in one direction. But the other template strand has to be replicated discontinuously, which means there has to be multiple primers on that template strand. Eventually what happens is that one template is completely replicated, but a short section of the other template gets lost, because of the lack of a primer. That lost section is a telomere.

Imagine that happening every time a cell divides. Eventually important genes get lost. The cells have an incomplete solution to that called telomerases, but they don't replace the lost template with the same info, they just randomally make stuff up. So that gene info is still lost.

Eventually the cell's function degrades due loss of gene info, leading to cell death.

My thoughts were that even if the cell goes back to an indifferentiated state which involves reprogramming the genome with proteins, it still needs a solution to the end-replication problem (loss of gene info with each cell division) to really be immortal.

[Narz]

I wish I could go back to being a teenager again.

[peter grimes]

Nah, too scary. I'm shocked by some of the things I did back then.

[Narz]

Well I want to keep my adult brain, I just want my teenage body back (my nineteen year old one).

[civ_king]

you would be a baby first Narz

[Harbringer]

So it may be immortal life, but its pretty much being born again, regenerating the brain tissues would make you lose all of your info man, making the process useless I would think, it would literally be like like being born again while your still alive.