Purpose of this research

The phenomenon of life is considered to be based on the "cooperative" functioning of nanosystems composed of a small number of molecules. The cooperative sliding movements of multiple actin and myosin filaments during muscular contraction is one such example. Numerous researchers have reported their observation of the elementary processes involving single molecules, such as in the actin-myosin system. However, there is hardly any report that describes the cooperativity among "small number of molecules" during the elementary processes in live cells. Therefore, it is difficult to understand the underlying mechanisms resulting in extremely high cooperativity among these molecules. While such cooperativity can confer some degree of stability or robustness to the reaction output, owing to the existence of a selective mode, it may also result in output plasticity because of the non-deterministic nature arising from the violation of concentration concept of biomolecules. Such factors can affect the operational stability and instability of macroscopic life system across hierarchy, which is extremely important to understand how life operates. However, due to the lack of a distinct theory regarding the mechanisms by which limited numbers of molecular react inside the cells, researchers have not focused on advanced techniques to measure and determine intracellular behavior of these molecules. In this project, we aim to establish an appropriate theory that will aid in future experiments on biological systems.

Content of this research on innovative area

In this research, we will focus on the "chemical reaction systems composed of limited number of molecules which exist in between single and multiple molecules," and will conduct research on an innovative area known as "minority biology" by using an interdisciplinary approach that includes micro-optics, MEMS engineering, fluorescence physical chemistry, synthetic organic chemistry, protein engineering, and mathematical science. For the technical development, experiments, and theories, we will consider the different viewpoints of the experts regarding their respective fields. We will mostly focus on the cooperativity among biomolecules based on the chemical reaction, ultracoherence, self-organization, Poisson property, ergodic property, multiple hierarchical interaction, and so on.

Expected achievement

Our aim is to conduct unconventional, cutting-edge, and creative research by addressing previously mentioned important issues through new approaches based on collaborations with interdisciplinary team members. Such research results will not only contribute to answer "What is life” (that is a difficult question to address using conventional research), but also bring about significant paradigm changes in the field of chemistry and physics. In this project, young members will take part in research planning in order to foster their educational and research activities. We believe that our research activity will contribute greatly to the far-reaching development in the fields of science and engineering in Japan.