Sir John B Gurdon shares his birthday with father of our nation. Born on October 2, 1933 in United Kingdom; Gurdon was a below average student. Despite his teacher’s ridicule he pursued his dream in sciences and became the brightest minds to be awarded a Nobel Prize in 2012.
In Oxford as a post graduate student he discovered for the first time that every cell in the organism contains the same genes, including the fertilized eggs from which they are derived. He transferred the nuclei of adult frog intestine into the egg cells, which grew into a clone of the adult frog. His work was based on work on Thomas King and Robert Briggs (USA), who concluded that the nuclear transfer
does not produce normal development. The story behind his success also depended on the strategy chosen. He worked with the amphibian Xenopus that lays egg when injected with mammalian hormone; so as to have copious amount of material. He started his work with endoderm that had large cells making it convenient for his kind of work; also that the intestinal cells keep proliferating. His work clearly demonstrated the totipotency of transplanted nucleus.
The road to success was not easy, his initial experiments failed, the Xenopus eggs prevented the insertion of micropipette that transferred the nucleus. This problem was sorted with exposure to proper frequency of UV light that softened the tough coating on Xenopus eggs. UV light also enucleated the egg by damaging the native DNA and allowed inserted nucleus to initiate development. Gurdon could now produce normal tadpoles. He further verified his results by using nuclei from mutated animals and proved that the frogs were developed using donor nuclei. Finally he chose to use nuclei from fully differentiated cells (intestinal) and reported his findings in in "Adult Frogs Derived from the Nuclei of Single Somatic Cells,"
Nearly after five decades of his work, the same could be repeated in mammalian systems through cloning of Dolly by Ian Wilmut, and Hoechedlinger’s experiments in mammalian cells. He shared the Nobel Prize with Shinya Yamanaka in Physiology or medicine in 2012 for their work in cloning and pluripotent stem cells.
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