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Sir John Gurdon: godfather of cloning. Interviewed by Ruth Williams.

Gurdon SJ - J. Cell Biol. (2008)

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Sir John Gurdon's famous frog cloning experiments of the 1960s and ’70s answered a question that had been hanging over cell biologists since before the turn of the century: are the cells of an adult organism genetically identical to the fertilized egg from which they are derived? In 2006, Shinya Yamanaka from Kyoto University reported that adult fibroblasts can be reprogrammed into embryonic stem cells by stably transducing them with four factors... One is that you start immediately... The second is that you do not study the subject in which you took the entrance exam. ” …Yes... But I could never make these phage work properly, I couldn't handle them at all... After a year of trying, I gave up and went back to working with embryos, but with the great benefit of having had a year's education at Caltech... There's no doubt about that... But if you're wise, you gratefully accept it and take advantage of it. …Nuclear transfer is still the most effective way of deriving embryo cells from adult cells... The very clever Yamanaka approach works, but only about 1 in 5,000 cells will make the transition... You're trying to derive one kind of cell—a heart or brain cell—from another, easily accessible cell—a skin or bone marrow cell... And the efficiency with which an egg can cause a complete switch, such as from skin to muscle, is something like 30%, compared with 1 in 5,000 for the IPS route... But it's very unlikely that eggs use just those four gene products. …Some people think that perhaps the fibroblasts go through a particular phase of the cell cycle in which they happen to be receptive to the four Yamanaka factors... Others, including Yamanaka himself, think that maybe the four factors have to arrive in the cell at an exactly precise ratio... We've been doing some work describing the histone states of genes during reprogramming by nuclear transfer... It might be that by altering the histone state of genes that are the targets of the Yamanaka factors, we might make those genes more receptive and thus increase reprogramming efficiency.

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HeLa cell nuclei (top) appear quite different after being reprogrammed inside a frog egg (bottom).
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fig2: HeLa cell nuclei (top) appear quite different after being reprogrammed inside a frog egg (bottom).


Sir John Gurdon: godfather of cloning. Interviewed by Ruth Williams.

Gurdon SJ - J. Cell Biol. (2008)

HeLa cell nuclei (top) appear quite different after being reprogrammed inside a frog egg (bottom).
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2315664&req=5

fig2: HeLa cell nuclei (top) appear quite different after being reprogrammed inside a frog egg (bottom).

View Article: PubMed Central - PubMed

AUTOMATICALLY GENERATED EXCERPT
Please rate it.

Sir John Gurdon's famous frog cloning experiments of the 1960s and ’70s answered a question that had been hanging over cell biologists since before the turn of the century: are the cells of an adult organism genetically identical to the fertilized egg from which they are derived? In 2006, Shinya Yamanaka from Kyoto University reported that adult fibroblasts can be reprogrammed into embryonic stem cells by stably transducing them with four factors... One is that you start immediately... The second is that you do not study the subject in which you took the entrance exam. ” …Yes... But I could never make these phage work properly, I couldn't handle them at all... After a year of trying, I gave up and went back to working with embryos, but with the great benefit of having had a year's education at Caltech... There's no doubt about that... But if you're wise, you gratefully accept it and take advantage of it. …Nuclear transfer is still the most effective way of deriving embryo cells from adult cells... The very clever Yamanaka approach works, but only about 1 in 5,000 cells will make the transition... You're trying to derive one kind of cell—a heart or brain cell—from another, easily accessible cell—a skin or bone marrow cell... And the efficiency with which an egg can cause a complete switch, such as from skin to muscle, is something like 30%, compared with 1 in 5,000 for the IPS route... But it's very unlikely that eggs use just those four gene products. …Some people think that perhaps the fibroblasts go through a particular phase of the cell cycle in which they happen to be receptive to the four Yamanaka factors... Others, including Yamanaka himself, think that maybe the four factors have to arrive in the cell at an exactly precise ratio... We've been doing some work describing the histone states of genes during reprogramming by nuclear transfer... It might be that by altering the histone state of genes that are the targets of the Yamanaka factors, we might make those genes more receptive and thus increase reprogramming efficiency.

Show MeSH