Nobel prizes announced

The Nobel Prize in physiology and medicine has been announced.  John B. Gurdon and Shinya Yamana have been awarded the prize jointly for discovering that you can ‘reset’ differentiated cells to an embryonic stage.  I’m going to have to pay Professor Gurdon a visit sometime soon.

In normal development, cells mature from their pluripotent state into various, specialized cell types a neuron, muscle cell, or skin cell, for example. For many years developmental biologists thought that the cellular maturation process was irreversible. In 1962, however, John Gurdon, working at the University of Oxford, showed that under the right conditions, a mature cell nucleus could become developmentally young again. Hereplaced the nucleus of a frog egg with a nucleus taken from a cell in a tadpole’s intestine. In a few cases, the egg cell was able to “reprogram” the DNA in the tadpole nucleus and the egg cell developed into an adult frog-the first animals cloned from mature cells*. Other researchers built on Gurdon’s findings, most famously the team that cloned Dolly the sheep using a similar feat of nuclear transplantation. That breakthrough demonstrated that mammal cells could undergo the same transformation from mature to immature.
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More than 4 decades later, Shinya Yamanaka showed that an egg cell wasn’t necessary to reprogram a cell’s DNA to pluripotency. Working with mouse cells, Yamanaka and his colleagues found that by adding extra copies of four genes to skin cells growing in a laboratory dish, they could prompt the cells to act like embryonic stem (ES) cells, the pluripotent cells taken from early embryos. A few years later, Yamanaka and other teams showed that a similar technique could work on human cells. That has allowed scientists to establish stable, growing populations of cells from patients with diseases such as Amyotrophic Lateral Sclerosis. Researchers can study such cells, known as induced pluripotent stem (iPS) cells for disease insights. In the case of ALS, for example, they can prompt them to become muscle and nerve cells that mimic the problems seen in people with the condition. Yamanaka, who originally trained as an orthopedic surgeon, welcomed the Nobel honor with a note of caution about how quickly it might yield medical benefits. “I feel great joy, but at the same time a great responsibility. The iPS technology is new and we actually have not been able to apply these findings to the development of new therapies or drugs. I feel we have to continue research to make a contribution to society as early as possible.”