Fine Art

Roger Kornberg in 2006, at the Fairchild Auditorium at Stanford University

Roger D. Kornberg

Born April 24, 1947 (1947-04-24) (age 60)
St. Louis, Missouri, United States
Residence United States
Nationality United States
Fields Structural biology
Institutions Stanford University,
Hebrew University of Jerusalem,
Harvard Medical School
Alma mater Harvard University (undergraduate),
Stanford University (PhD)
Known for Transmission of genetic information from DNA to RNA
Notable awards Nobel Prize in Chemistry (2006),
Louisa Gross Horwitz Prize (2006)

Roger David Kornberg (born April 24, 1947 ) is an American biochemist and professor of structural biology at Stanford University School of Medicine.

Kornberg was awarded the Nobel Prize in Chemistry in 2006 for his studies of the process by which genetic information from DNA is copied to RNA, "the molecular basis of eukaryotic transcription."[1][2] His father, Arthur Kornberg, who was also a professor at Stanford University, was awarded the Nobel Prize in Medicine in 1959.

He also holds an honorary doctorate from Umeå University in Sweden.

Biography

Kornberg was born in St. Louis, Missouri to a Jewish family. He was the first of three children born to biochemists Arthur Kornberg and his wife, Sylvy (née Levy), who worked together.

Roger Kornberg earned his bachelor's degree from Harvard University in 1967 and his Ph.D. from Stanford in 1972. He then became a postdoctoral fellow at the Laboratory of Molecular Biology in Cambridge England.

Scientific Discoveries and Nobel Prize

All organisms are controlled by their genes, which are coded by DNA, which is copied to RNA, which creates proteins, which are sequences of amino acids. DNA resides in the nucleus. When a cell expresses a gene, it copies (transcribes) that gene's DNA sequence onto a messenger RNA (mRNA) sequence. mRNA is transported out of the nucleus to ribosomes. The ribosomes read the mRNA and translate the code into the right amino acid sequence to make that gene's protein.

The DNA is transcribed to mRNA by an enzyme, RNA polymerase II, with the help of many other proteins. Using yeast, Kornberg identified the role of RNA polymerase II and other proteins in transcribing DNA, and he created three-dimensional images of the protein cluster using X-ray crystallography. Polymerase II is used by all organisms with nuclei, including humans, to transcribe DNA.

Roger Kornberg and his research group have made several fundamental discoveries concerning the mechanisms and regulation of eukaryotic transcription. While a postdoctoral fellow working with Aaron Klug and Francis Crick at the MRC in the 1970s, Kornberg discovered the nucleosome as the basic protein complex packaging chromosomal DNA in the nucleus of eukaryotic cells (chromosomal DNA is often termed "Chromatin" when it is bound to proteins in this manner, reflecting Walther Flemming's discovery that certain structures within the cell nucleus would absorb dyes and become visible under a microscope.).[3] Within the nucleosome, Kornberg found that roughly 200 bp of DNA are wrapped around an octamer of histone proteins.

Kornberg's research group at Stanford later succeeded in the development of a faithful transcription system from baker's yeast, a simple unicellular eukaryote, which they then used to isolate in a purified form all of the several dozen proteins required for the transcription process. Through the work of Kornberg and others, it has become clear that these protein components are remarkably conserved across the full spectrum of eukaryotes, from yeast to human cells.

Using this system, Kornberg made the major discovery that transmission of gene regulatory signals to the RNA polymerase machinery is accomplished by an additional protein complex that they dubbed Mediator.[4] As noted by the Nobel Prize committee, "the great complexity of eukaryotic organisms is actually enabled by the fine interplay between tissue-specific substances, enhancers in the DNA and Mediator. The discovery of Mediator is therefore a true milestone in the understanding of the transcription process."[5]

At the same as Kornberg was pursuing these biochemical studies of the transcription process, he devoted two decades to the development of methods to visualize the atomic structure of RNA polymerase and its associated protein components. Initially, Kornberg took advantage of expertise with lipid membranes gained from his graduate studies to devise a technique for the formation of two-dimensional protein crystals on lipid bilayers. These 2D crystals could then be analyzed using electron microscopy to derive low-resolution images of the protein's structure. Eventually, Kornberg was able to use X-ray crystallography to solve the 3-dimensional structure of RNA polymerase at atomic resolution.[6][7] The structure of RNA polymerase obtained by Kornberg is the most complex protein structure solved to date. He has recently extended these studies to obtain structural images of RNA polymerase associated with accessory proteins.[8]Through these studies, Kornberg has created an actual picture of how transcription works at a molecular level. According to the Nobel Prize committee, "the truly revolutionary aspect of the picture Kornberg has created is that it captures the process of transcription in full flow. What we see is an RNA-strand being constructed, and hence the exact positions of the DNA, polymerase and RNA during this process."[9]

In 1959, Roger Kornberg's father, Arthur Kornberg, received the Nobel Prize in Physiology or Medicine for studies of how genetic information is transferred from one DNA molecule to another in a process called DNA replication. Specifically, Arthur Kornberg isolated the first enzyme capable of synthesizing DNA, bacterial DNA polymerase I, which was then the first known enzyme to take its instructions from a template, thus ensuring the conservation of genetic information during cellular growth and division. Roger Kornberg's younger brother, Thomas Bill Kornberg, discovered DNA polymerases II and III in 1970 and is now a geneticist at the University of California, San Francisco. All three Kornbergs have thus worked to understand how genetic information is put to use in cells. Roger and Arthur Kornberg are the sixth father-son pair to win Nobel Prizes.

Awards

He has received the following awards:

* 1997: Harvey Prize from the Technion - Israel Institute of Technology

* 2002: ASBMB-Merck Award

* 2002: Pasarow Award in Cancer Research

* 2002: Le Grand Prix Charles-Leopold Mayer

* 2005: General Motors Cancer Research Foundation’s Alfred P. Sloan Jr. Prize[10]

* 2006: Nobel Prize in Chemistry

* 2006: Louisa Gross Horwitz Prize from Columbia University

Nobel Laureate Roger Kornberg: "The End of Disease"

References

1. ^ Roger Kornberg wins the 2006 Nobel Prize in Chemistry. Stanford University School of Medicine.

2. ^ Press release: The Nobel Prize in Chemistry 2006. Royal Swedish Academy of Sciences.

3. ^ Kornberg, R.D. (1974) Chromatin structure: a repeating unit of histones and DNA. Science 184, 868-871.

4. ^ Kelleher III, R.J., Flanagan, P.M. and Kornberg, R.D. (1990) A novel mediator between activator proteins and the RNA polymerase II transcription apparatus. Cell 61, 1209-1215.

5. ^ The Nobel Prize in Chemistry 2006

6. ^ Cramer, P., Bushnell, D.A. and Kornberg, R.D. (2001) Structural basis of transcription: RNA polymerase II at 2.8 ångstrom resolution. Science 292, 1863-1876.

7. ^ Gnatt, A.L., Cramer, P., Fu, J., Bushnell, D.A. and Kornberg, R.D. (2001) Structural basis of transcription: An RNA polymerase II elongation complex at 3.3 Å resolution. Science 292, 1876-1882.

8. ^ Bushnell, D.A., Westover, K.D., Davis, R.E. and Kornberg, R.D. (2004) Structural basis of transcription: An RNA polymerase II – TFIIB cocrystal at 4.5 angstroms. Science 303, 983-988.

9. ^ A family story about life 2006

10. ^ The 2005 Alfred P. Sloan, Jr. Laureate. Retrieved on 2006-10-04.

Chemistry Encyclopedia

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