Concept 24 The RNA message is sometimes edited.

Richard Roberts Phillip Sharp Richard Roberts and Phil Sharp shared the 1993 Nobel Prize for the discovery of the split gene theory.

Phillip Allen Sharp (1944-)

Phillip Sharp

Phillip (Phil) Sharp was born in rural Kentucky. He grew up on a farm, and while not particularly interested in biology, Sharp did enjoy his science and math classes in school. His parents encouraged him to go to college, and Sharp earned his tuition by raising cattle and growing tobacco.

Sharp went to Union College, a small liberal arts school. He majored in chemistry and math and went on to the University of Illinois for graduate school. His thesis project was on the description of DNA. It was more physical chemistry as opposed to experimental molecular biology.

In 1966, Cold Spring Harbor Laboratory held a symposium on The Genetic Code. Sharp read the symposium volume and became interested in molecular biology and genetics. When he started looking for a post-doc in 1969, Sharp applied and was accepted to work with Norman Davidson at the California Institute of Technology - a lab working on problems relating to the phage and bacterial genomes. Sharp learned how to use techniques like electron microscopy to experiment and test theories. Sharp worked with and studied bacterial plasmids, and figured out that plasmids that confer sex or drug resistance have transposable elements.

In 1971, Sharp did another post-doc at Cold Spring Harbor Laboratory. James Watson was his supervisor, but because he was still at Harvard, Sharp worked more closely with Joe Sambrook. Sharp was interested in gene expression and worked with simple viruses, like SV40 and adenovirus. Using restriction enzymes, which had just been discovered, and an adapted gel electrophoresis technique, Sharp mapped the adenovirus genome. He and his colleagues then mapped the adenoviral mRNAs and linked them to function.

These experiments were started at Cold Spring Harbor and continued at Massachusetts Institute of Technology where in 1974, Sharp was offered a job at the Center for Cancer Research. Sharp and his colleagues noticed that long nuclear RNA did not exist in the cytoplasm. They speculated that these long nuclear RNAs were processed into shorter mRNAs. Using RNA/DNA hybrids, they showed that cytoplasmic mRNA was processed and edited. This led to the split gene theory for which Sharp shared the 1993 Nobel Prize for Physiology or Medicine.

In 1978, Sharp and a group of other scientists, including Walter Gilbert, founded Biogen Inc., one of the first biotech companies. It is now centered in Boston and is currently the only non-conglomerated biotech company. Sharp is the Chairman of the Scientific Board at Biogen and a member of its Board of Directors.

In 1985, Sharp became the director of the Center for Cancer Research after Salvador Luria retired. In 1991, he stepped down as director and became the head of the Department of Biology at MIT. His tenure as head of the department ended in 1999 and he is currently Institute Professor.

In addition to the Nobel, Sharp has won numerous prizes for his work. Until 1995, Sharp was on the editorial board for the journal Cell and is a member of many scientific organizations like the National Academy and the American Philosophical Society. He has served as a member of the President's Advisory Council on Science and Technology and on a number of search committees and peer-review government granting agencies like the NIH.

factoid Did you know ?

Rich Roberts is one of the first DNA forensic expert witnesses. He verified DNA fingerprint data and testified in court as to its validity.


How does a cell know the difference between an intron and and exon? How does the cells put together the right combination of exons to makes messenger RNA?