A biochemist who has given a tremendous impetus to the development of life sciences. He has contributed greatly to the construction of the fundamental concepts of intracellular signal transduction cascade through his discovery of "protein kinase C," also known as "C kinase," and his analysis of its function, which revealed a new intracellular signal transduction system and elucidated the regulatory mechanisms involved in many biological phenomena, including cancer cell growth.
Dr. Yasutomi Nishizuka is an eminent biochemist who, through his discovery and analysis of protein kinase C, also known as C kinase, has elucidated a new intracellular signal transduction system, thereby clarifying regulatory mechanisms for a great variety of biological phenomena as well as tumorgenesis, and exerting a major influence upon the progress of the life sciences.
In 1977, Dr. Nishizuka discovered a calcium ion-activated, cyclic nucleotide-independent protein kinase and designated his enzyme “C kinase.”
A particularly important research result obtained by Dr. Nishizuka in connection with C kinase was the discovery that this enzyme is activated in coordination with calcium ions by a second messenger, diacylglycerol, produced by hydrolysis of phospholipids contained in the cell membranes. This revealed the existence of a new protein kinase system.
Subsequently, Dr. Nishizuka demonstrated that, through calcium ions and the metabolism of phospholipids, C kinase serves to transmit external information to cells in the manner of an amplifier, and that the tumorgenic promoter phorbol ester activates C kinase, indicating that C kinase is intimately involved in the mechanisms of cell proliferation and tumorgenesis.
Furthermore, during the latter half of the 1980s, Dr. Nishizuka succeeded in cloning C kinase genes. He pointed out the existence of several types of C kinase and demonstrated that these various enzymes act by sharing functions in a complex information transmission system.
Through the discovery of a key enzyme and intensive research in connection with this enzyme, the achievements of Dr. Nishizuka established the existence of an intracellular signal transduction mechanism as the pivot of a major system governing various biological functions. In the years 1984 and 1986, his research papers summarizing these results ranked first in the world in terms of frequency of citation in the literature, thus reflecting the interest evoked by these results in international scientific circles. This series of research achievements by Dr. Nishizuka has had an incalculably vast impact in the fields of biology and medicine.
This record of outstanding research achievements duly attests to the preeminent qualifications of Dr. Yasutomi Nishizuka as the laureate of the 1992 Kyoto Prize for Basic Sciences.
A chronicle delineating the career of one who has dedicated his or her life to scientific work normally consists of a series of fortunate incidents involving nature as well as many converging paths shared with other scientists, and in retrospect on several decades, numerous episodes of both joy and sorrow will have been woven into his or her scientific life.
Of the natural sciences, the life sciences in particular deal with phenomena far too complex, excepting the immobile, inanimate matter, and it is not simple for the individual researcher to command the vast amount of heterogeneous information involved. There is, naturally, little that one can do by oneself. For this reason, leaning from other scientists, just as learning from nature, is of incalculably great significance.
Today, the word “communication” is on everybody’s lips. In fact, the research area that is related to “communication” is becoming more and more important in the life sciences. The human body normally consists of trillions of cells, and these cells are all the time communicating with one another. Our lives are made possible by superbly controlled and well-coordinated cell-to-cell communications, such as those between the brain cell function and muscle cell contraction, the heart beat and blood pressure control, and so on. In physiological processes, numerous biologically active substances including hormones and neurotransmitters facilitate smooth functioning, acting as lubricants, so to speak.
In the past, researchers might comprehend only certain aspects of the fundamental processes commonly observed in all of such a vast number of cell populations. At present, we are becoming aware of the molecular mechanisms of an elaborate network of cell-to-cell communications. These endeavors are motivated by the fact that malfunctions of these cell-to-cell communications may result in the development of diseases such as cancer, memory defects, and heart diseases. It is now clear that elucidation of the mechanisms involved in such physiologically important communications will facilitate progress in the treatment and prevention of the ailments affecting our daily life.
Many things are needed to undertake research work and make it a success. But there is one indispensable element: communication with scientists struggling with the riddles of nature, both at home and abroad throughout this wide world, is a must.
I shall be extremely happy if I can present such topics that are related to cell-to-cell communication and stimulate discussion on the progress achieved to date and the prospects for the future in this particular field.