Susumu Tonegawa (利根川 進 Tonegawa Susumu, born September 6, 1939) is a Japanese scientist who won the Nobel Prize for Physiology or Medicine in 1987 for "his discovery of the genetic principle for generation of antibody diversity." Although he won the Nobel Prize for his work in immunology, Tonegawa is a molecular biologist by training. In his later years, he has turned his attention to the molecular and cellular basis of memory formation. September 6 is the 249th day of the year (250th in leap years). ... 1939 was a common year starting on Sunday (link will take you to calendar). ... This article is about the profession. ... List of Nobel Prize laureates in Physiology or Medicine from 1901 to the present day. ... 1987 is a common year starting on Thursday of the Gregorian calendar. ... Genetics (from the Greek genno γεννώ= give birth) is the science of genes, heredity, and the variation of organisms. ... Schematic of antibody binding to an antigen An antibody is a protein used by the immune system to identify and neutralize foreign objects like bacteria and viruses. ... Immunology is a broad branch of biomedical science that covers study of all aspects of the immune system in all organisms. ... Molecular biology is the study of biology at a molecular level. ... In science, a molecule is the smallest particle of a pure chemical substance that still retains its chemical composition and properties. ... Cells in culture, stained for keratin (red) and DNA (green) The cell is the structural and functional unit of all living organisms, sometimes called the building blocks of life. ... Memory is a property of the human mind: the ability to retain information. ...

To achieve the diversity of antibodies needed to protect against any type of antigen, the immune system would require millions of genes coding for different antibodies, if each antibody was encoded by one gene. Instead, as Tonegawa showed in a landmark series of experiments beginning in 1976, genetic material can rearrange itself to form the vast array of available antibodies. Comparing the DNA of B cells (a type of white blood cells) in embryonic and adult mice, he observed that genes in the B cells of the older mice are moved around, recombined, and deleted to form the diversity of the variable region of antibodies. The immune system is the organ system that protects an organism from outside biological influences. ... This stylistic schematic diagram shows a gene in relation to the double helix structure of DNA and to a chromosome (right). ... 1976 is a leap year starting on Thursday (link will take you to calendar). ... Space-filling model of a section of DNA molecule Deoxyribonucleic acid (DNA) or deoxyribose nucleic acid is a nucleic acid that contains the genetic instructions specifying the biological development of all cellular forms of life (and many viruses). ... B cells are lymphocytes that play a large role in the humoral immune response (as opposed to the cell-mediated immune response). ... White blood cells (also called leukocytes or immune cells) are a component of blood. ... A mouse is a mammal that belongs to one of numerous species of small rodents in the genus Mus and various related genera of the family Muridæ (Old World Mice). ...

Tonegawa was born in Nagoya, Japan. He received his bachelor's degree from Kyoto University in 1963. He received his doctorate from the University of California, San Diego. He did post-doctoral work at the Salk Institute in San Diego, then worked at Basel Institute for Immunology in Basel, Switzerland, where he performed his landmark immunology experiments. In 1981, he became a professor at the Massachusetts Institute of Technology. Nagoya Castle in June of 2004. ... Kyoto University in Kyoto, Japan (京都大学 Kyōto Daigaku; abbreviated to 京大 Kyōdai) is the second oldest university of Japan and one of leading national universities having a total of roughly 22,000 students. ... The University of California, San Diego (popularly known as UCSD) is a public, coeducational university located in La Jolla, California. ... The Salk Institute for Biological Studies is a research organization in La Jolla, California. ... San Diego County in the Southwest corner of California. ... Basel (English traditionally: Basle [ba:l], German: Basel [ba:z@l], French Bâle [ba:l], Italian Basilea [bazilE:a]) is Switzerlands third most populous city (188,000 inhabitants in the canton of Basel-City as of 2004; the 690,000 inhabitants in the conurbation stretching across the immediate... The Massachusetts Institute of Technology, or MIT, is a research institution and university located in the city of Cambridge, Massachusetts directly across the Charles River from Bostons Back Bay district. ...

External links

• Nobel Prize Biography
• Tonegawa's bio at MIT
• Tonegawa's research at the Center for Learning and Memory
• his discovery of the genetic principle for generation of antibody diversity