Editor's Choice Main Category: Stem Cell Research Also Included In: Biology / Biochemistry Article Date: 08 Oct 2012 - 10:00 PDT
Current ratings for: Nobel Prize For British And Japanese Stem Cell Scientists
The Nobel Assembly described their findings as a revolution in our understanding of how organisms and cells develop. Gurdon and Yamanaka discovered that mature, specialize cells may be reprogrammed so that they revert back into immature cells that have the potential of developing into all tissues of the body.
The specialization of cells is reversible - in 1962, John Gurdon discovered that a cell's specialization can be reversed. In a famous experiment, he took out the nucleus of a frog's egg cell and replaced it with the nucleus from a mature intestinal cell. The egg with the gut cell nucleus eventually developed into a healthy tadpole. The mature cells' DNA still carried all the data required to developed into all cells in the frog.
Reprogramming intact mature cells into immature stem cells - in 2006, Yamanaka discovered how an intact mature cell in a mouse could be reprogrammed so that it turned into an immature stem cell. With the introduction of just a few genes he managed to reprogram mature cells so that they became pluripotent stem cells. Pluripotent stem cells can develop into any type of cell in the body.
In a communiqu, Nobelprize.org wrote:
As the embryo develops, these cells develop into liver cells, muscle cells, nerve cells - into all the cell types required to form a developed organism. Each cell is specialized to perform precise functions in the adult body.
Scientists had thought that the journey from immature to specialized cells was a one-way-street; that there was no turning back, that it would not be possible for them to return to an immature, pluripotent state.
John B. Gurdon wondered how right this theory was, and decided to challenge it. He hypothesized that a specialized cell's genome may still have all the data required to drive its development into any type of cell. He tested his hypothesis in 1962. He replaced a frog's egg cell nucleus with the mature, specialized cell from a tadpole's intestine.
The frog's egg cell with the nucleus of the cell of a tadpole's intestine developed into a healthy, cloned tadpole. He repeated the experiment several times and managed to yield many adult frogs.
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Nobel Prize For British And Japanese Stem Cell Scientists