Gurdon and Yamanaka share Nobel Prize in Physiology or Medicine 2012
Oct08

Gurdon and Yamanaka share Nobel Prize in Physiology or Medicine 2012

British scientist John B. Gurdon and Shinya Yamanaka (MD, PhD!), a Japanese scientist now at the Gladstone Institutes in San Francisco, were awarded the Nobel Prize in Physiology or Medicine this morning,  "for the discovery that mature cells can be reprogrammed to become pluripotent." Briefly, Gurdon and colleagues showed that the genetic information from a mature, differentiated cell still had the ability to program an undifferentiated embryonic cell to develop into an adult organism. That is, an embryonic cell contains the chemical signals to use adult DNA to drive development of a new organism. The work was done with the frog, Xenopus laevis, and the technique came to be known as "nuclear transfer." In colloquial terms, this is "cloning." Current press reports are citing Gurdon's work as occurring in 1962 but studies appear to have been published in Nature as early as 1958. Christen Brownlee composed a superb summary of nuclear transfer for the Classics section of the Proceedings of the National Academy of Sciences. Gurdon's work stemmed from 1952 experiments of Robert Briggs and Thomas J. King with another frog, Rana pipens. Briggs died in 1983 and King in 2000 and could not be recognized with the Nobel. This fact relieved the Nobel committee, in my opinion, from having to decide which scientist would have been awarded the potential third slot for the prize. (Addendum 7:18 am EDT): I suspect that some argument will arise in support of UW-Madison's James A. Thomson for the third slot as the Science paper from his group came out concomitantly with Yamanaka's Cell paper. 8:21 am: The Guardian's Alok Jha just reminded me that I overlooked Takahashi and Yamanaka's earlier Cell paper from 2006. However, C&EN's Carmen Drahl is now reporting this 2001 TIME magazine cover with Thomson.) The conceptual originator of the technique, Germany's Hans Spemann, was given the 1935 Nobel Prize in Physiology or Medicine for identifying how different parts of the embryo lead to each segment of the adult organism. Shinya Yamanaka, now at the tender age of 50, had earlier led studies to convert adult human cells back into the fully undifferentiated state. These are today called induced pluripotent stem cells or iPS. The term "pluripotent" means that the cells can divide into any other mature cell type: live, brain, muscle, etc. In 2006 while at Kyoto University, Yamanaka's group demonstrated that only four genes were required for reprogramming a skin cell into a pluripotent stem cell: SOX2, Oct-3/4, Klf4, and c-Myc. These four genes encoding proteins called transcription factors, regulators of specific patterns of genes to be turned on or off. The average science reader is likely to at...

Read More
Gooood morning, Santiiiiago!
Dec02

Gooood morning, Santiiiiago!

I love my blogs and my readers. Last Friday morning, I had the delight of Skyping in to a medical school bioethics class at Universidad Finis Terrae to discuss the virtues and pitfalls of animal research. I was contacted earlier in the week by an email from Xaviera Cardenas, a first-year medical student at this university in Santiago, Chile, who was looking for an international scientist to hold forth on this topic. Readers of CENtral Science know that any novel chemical you synthesize must undergo some animal testing before it can be used in people. This is not our choice as individuals but, instead, a requirement of our regulatory authorities. Despite advances with in vitro technologies, testing in a limited number of rodent and non-rodent species is absolutely required. I spoke specifically to the class about my service on NIH study sections where we take very seriously the review of vertebrate animal use in research. No matter the quality of the science, grant awards can be specifically withheld due to inattention to the five requirements to justify and assure responsible and humane use of vertebrate animals for research and testing. I'm a real stickler for use of the minimum number of animals, a number that is carefully determined using power calculations based on the minimum expected change in a biological outcome. Researchers must assure that animals will be managed by a highly-qualified veterinarian with attention to avoiding or minimizing any pain and suffering. Because research animals cannot give informed consent, I sometimes see research animal protocols getting more scrutiny that human clinical trial protocols. Xavi and her class asked me about these and other issues during our 20 minute visit last week. Her professor played the role of devil's advocate by dressing up as a beagle but, unfortunately, a photograph was not made available to the blog. I asked Xavi to share her recollections on the experience. She's very kind and her English is definitely superior to my Spanish. Thanks, Xavi, for the chance to speak with your class. And don't worry, I'll be down sometime to experience the wines of Chile!   The power of internet Xaviera Cardenas Has anyone thought how can you be in two places at the same time? It sounds perfect for a sci-fi novel implying teleportation… or evil twins. But last Friday, David was able to comfortable be in his house and at a presentation in Santiago, Chile without stepping on a plane. That Friday morning was pretty hectic for most of the students who were at the Bioethics class imparted by Universidad Finis Terrae. It was our final class in which we...

Read More