Shinya Yamanaka

Stem cell researcher

• Born: September 4, 1962
• Place of Birth: Place of birth: Osaka, Japan

Significance: Shinya Yamanaka is a Japanese stem cell researcher who gained worldwide recognition for his discovery in the mid-2000s that adult cells could be genetically converted into stem cells. In medicine, stem cells are used to regrow tissues that have broken down due to disease. Yamanaka was awarded the 2012 Nobel Prize in medicine for his work. He served as director of the Center for iPS Cell Research and Application at Kyoto University and as a professor at the University of California, San Francisco.

Background

Shinya Yamanaka was born in Osaka, Japan, on September 4, 1962. His father, Shozaburo, was an engineer who operated his own manufacturing plant in the city of Higashiosaka. His mother, Minako, helped run the factory while raising Yamanaka and his sister, Yumiko.

Yamanaka entered Tennoji Junior High School in 1975. Over the next six years, he decided he would pursue a degree in medicine to become a physician. He graduated from Tennoji in 1981 and that same year was accepted into Kobe University's school of medicine.

Yamanaka participated in numerous sports during his tenure at the university. He became interested in sports medicine from these experiences and ultimately decided to become an orthopedic surgeon. He received his degree in medicine from Kobe University in 1987.

Yamanaka then began a two-year residency at Osaka National Hospital. It was here that he learned he was not suited to performing surgery. He struggled to complete operations, and his supervisors discouraged him from continuing his current career path.

Yamanaka then decided to become a medical researcher. In 1989, he became a doctoral student in pharmacology at Osaka City University Graduate School of Medicine. Over the next four years, he learned how to plan and execute laboratory experiments and analyze the results. Yamanaka earned his doctorate in pharmacology in 1993.

Life's Work

Having completed the necessary education, Yamanaka began seeking postdoctoral work in molecular biology, since he had experimented with gene replacement in mice while earning his doctorate. Gene replacement, or gene targeting, involves isolating, examining, and either removing or replacing genes in an organism to produce biological effects.

With no professional experience in this field, Yamanaka initially had difficulty finding a postdoctoral position. He eventually was accepted at the Gladstone Institute of Cardiovascular Diseases at the University of California, San Francisco (UCSF). There, he continued studying gene targeting in mice, learning how to grow mouse embryonic stem cells to create chimeras, or genetically engineered organisms.

Yamanaka returned to Japan in 1996 to become an assistant professor of pharmacology at Osaka City University Graduate School of Medicine. He tried to continue his research into mouse stem cells but could not acquire the necessary funding or assistance in the Japanese scientific community. In 1999, Yamanaka was granted his own laboratory as an associate professor at the Nara Institute of Science and Technology (NAIST) in Japan's Nara Prefecture. He established as his long-term goal at the laboratory to cultivate embryonic stem cell–like cells from the somatic, or skin, cells of adults. Embryonic stem cells can be genetically reprogrammed and injected into individuals with diseases to heal their damaged tissues.

Yamanaka's research in this area was inspired by an earlier scientific revelation. This was American cell biologist James Thomson's announcement in 1998 that his laboratory at the University of Wisconsin-Madison had successfully generated human embryonic stem cells. This discovery was monumental because it meant that the need to destroy human embryos to create medicinal stem cells for people with diseases would start to decline. Yamanaka was relieved that he could now avoid the controversial practice of destroying human embryos for scientific research.

Yamanaka initially believed his goal of converting adult cells into stem cells was too ambitious to be achieved in his lifetime. However, he was determined to use nuclear reprogramming to experiment on his concept with mouse genes. Yamanaka was particularly confident in this method of embryonic stem cell generation because the cloned sheep Dolly had been created this way in 1997.

Over the next several years, Yamanaka and his team at NAIST identified twenty-four individual mouse genes they believed could be used to create pluripotency, or the potential of stem cells to develop into multiple types of cells, in adult somatic mouse cells. Yamanaka's experiments would require genetically engineering the adult cells with various genes to see which cells would begin to display the properties of an embryonic stem cell.

In 2004, Yamanaka moved his research to the Institute for Frontier Medical Sciences at Kyoto University so he could add lab-cultured human embryonic stem cells into his experiments. Finally, in 2005, Yamanaka succeeded in converting adult mouse cells into embryonic stem cell–like cells using only four genes. He named his discovery induced pluripotent stem cells, or iPS cells, and published his research the next year.

Yamanaka repeated the same success in 2007 on adult human somatic cells. Several months later, Kyoto University opened its Center for iPS Cell Research and Applications (CiRA) and named Yamanaka as its director. For his accomplishments, Yamanaka was awarded the Nobel Prize in medicine in 2012. In 2022, he became director emeritus of CiRA, while continuing his professorships at both Kyoto University and UCSF and conducting reseach into stem cell biology at the Gladstone Institute.

Impact

Yamanaka's successful creation of embryonic stem cells from adult cells was only the beginning of scientific research in this area. Yamanaka came to perfect his own method with repeated experiments. For instance, two of the four genes he had used to create the stem cells were linked to an increased risk of cancer. Yamanaka later discovered he could omit the more dangerous of these genes and produce the same result. His research helped the global medical community find ways to combat serious human diseases such as amyotrophic lateral sclerosis (ALS) and chronic infantile neurological cutaneous and articular (CINCA) syndrome.

Personal Life

Yamanaka married his wife, Chika, whom he had met in junior high school, in the late 1980s. They later had two daughters, Mika and Miki.

Bibliography

"Shinya Yamanaka – Biographical." Nobelprize.org. Nobel Media AB. Web. 1 June 2016.

"Yamanaka, Shinya." Cell, 20 June 2024, Vol. 187, No. 13, 3229 - 3230, www.cell.com/cell/fulltext/S0092-8674(24)00584-1. Accessed 1 Oct. 2024.

"Shinya Yamanaka, M.D., Ph.D." Academy of Achievement. American Academy of Achievement. Web. 1 June 2016.

"Shinya Yamanaka, MD, PhD." University of California San Francisco. Regents of the University of California. Web. 1 June 2016.