George Wells Beadle was born at Wahoo, Nebraska, on October 22, 1903. He was the son of farmers; his parents owned and operated a 40-acre (160,000 m2) farm.[1]
George might himself have become a farmer if one of his teachers had not directed his mind towards science, and the College of Agriculture at Lincoln, Nebraska.
In 1926, after his degree, he worked on hybridwheat andZea mays. In 1931 he was awarded a National Research Council Fellowship at theCalifornia Institute of Technology atPasadena, where he remained from 1931 until 1936. During this period he continued his work on Indiancorn and began, in collaboration withDobzhansky andSturtevant work oncrossing-over in the fruit fly,Drosophila melanogaster.
In 1935 Beadle visited Paris for six months to work withBoris Ephrussi at the Institut de Biologie physico-chimique. Together they began the study of the development of eye pigment inDrosophila which later led to the work on the biochemistry of the genetics of thefungusNeurospora.
In 1937 Beadle was appointed Professor of Biology (Genetics) at Stanford University and there he remained for nine years, working for most of this period in collaboration with Tatum.
In 1946 he returned to the California Institute of Technology as Professor of Biology and Chairman of the Division of Biology. Here he remained until January 1961 when he was elected Chancellor of theUniversity of Chicago and, in the autumn of the same year, President of this university.
Beadle died on June 9, 1989 at a retirement community inPomona, California from problems caused byAlzheimer's disease, aged 85.[2]
The work of Beadle & Tatum was continued later byE.B. Lewis who worked on the way genes control the development ofembryos, and byPhillip Sharp &Richard Roberts who discovered of introns andRNA splicing. All three won Nobel Prizes for their work.
In 1977, work by the Sharp and Roberts labs showed thatgenes of higher organisms are "split" or present in several distinct segments along theDNA molecule.[3][4]
The coding regions of the gene are separated by non-coding DNA that is not involved inprotein expression. The non-coding regions, theintrons, are cut from the precursor mRNAs in a process called "splicing". The split gene structure was found to be common to mosteukaryotic genes. For this reason, one gene–one enzyme does not hold in the simple way put forward by Beadle and Tatum. This is because
- It may take more than one gene to build a protein, and
- Many different genes can be made from a smaller set of genes (seeantibody).
However, their work was a great step forward in its time.
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