Why did we relieve what our amphibious ancestors can still be able to growing upwards at will? British researchers have now come to the secret now a stucco
"For this movie no animals suffered": the sentence that may not be missing in any Hollywood movie cripple, here he has no place. For the article a British research team published in the current ie of the Science Magazine Science, some grungy water loss suffered. If you want to examine how Notophthalmus Viridescens’s amputated limbs can be growing again, can not wait until a specimen is randomly in a underwater traffic accident or caught hair width from a magic: that must cut off the animal one of his legs.
After all, there is a more comforting fact: the pig succeeds, the woman has been worn for a long time, that to be so rooted to grow back. That this phenomenon looks so fascinating on us is clear: what happened to humans, he does not get back again. The twisted tooth, the cerebral cells swelled by the alcohol or the little finger landed in the circles – we can neither consciously nor unconsciously, what our stupid cousins from the animal kingdom are still dominating playing. Invertible animals can grow complete body from a cell heap, amphibians regenerate body members and other complex structures, while man with insufficient prosthetics has to tail. To come to the regeneration process more accurately to the track to imitate him, the science irritates for a long time.
How members regenerate from an adult grungy water molding (notophthalmism viridesscens) – left after an amputation in the center of spoke and Elle, right after an amputation in the upper arm bone (humerus).
And she has already got a lot. If a pig loses a part of his leg, some of his cells make their differentiation back again. They will voluntarily move to stem cells, move to the affected area and form a cell cluster, from which millimeters for millimeters forms a new leg. Nerve cells appear to play a crucial role. Nerves are not only there to transport information between sensor and engine cells. Parallel to the pile of stem cells at the leg stump, the blast, regenerate the "present" nerve cells.
Already in 1823 an English doctor could show that the presence of nerve cells (whether motor or sensory type) for regeneration is indispensable. Shorts the nerve connections a stucco in front of the leggers, the member does not grow after. Why that is, you could only suspect. It makes sense: a member that is not supplied from nerves, his owner will be little practicable. However, the nerve cells must not release neurotransmitters, nor do they have to transfer any impulses – they just have to be there.
But on which molecular basis, nerve cells and regenerating tie then communicate? The London research team has now managed to find a protein that takes this task. In addition, they followed a hint that the regenerating body gives: the blast is always exactly the structure that is being used – by the stump. At the wrist always grows a hand, no upper arm. But where does the blastem in which direction it must differentiate?
This note was already leading to the identification of a "PROD 1" mentioned protein, which can be determined in a gradient on the body member. The blastem must follow the track laid out by PROD1 only in decreasing direction. For this purpose, it uses a second protein that the scientists now identified in Science and called "Nag". That Nag is so important, they finished with an attempt: they removed the nerve cells from the leg membrane – usually no regeneration was allowed to do. Injected injected DNS fragments that coded Nag, and then stimulated the cells to record these fragments.
As a result, these cells could then synthesize NAG – and the regeneration continued again. There was a complete leg – only without nerve cells. The scientists now hope to be able to transfer their findings to suction animals. To that, you mean, but you have to understand the structure of the blastem better, for that there is no counter-piece in suction animals.