1. Outline of the plan for establishing the COE
The concept of G-COE program is carried over from the 21st Century Center of Excellence Program (21-COE) for "Understanding and Control of Life's Function via Systems Biology", and there will be a new emphasis on promoting international scientific exchanges between Japan and other countries. In this program, we will focus on Human Metabolomic Systems Biology and utilize cell and tissue resources collected from human to explore and mine out unknown mechanisms of metabolism systematically under physiologic and pathological conditions in vivo. To this end, our G-COE program aims to stimulate predoctoral students to use two important strategies: human animal experiments and metabolome-fluxome analyses.
Humanized animals, include superimmunodeficient NOG mice (mice lacking T- and B-cells and NK cells), where human-derived cancer cells or hepatocytes can survive without any notable rejection, or those which human artificial chromosome (HAC) is stably expressed in vivo. Another resource available in Japan is Common Marmoset (CM). CM is a non-human primate that shares characteristics of xenobiotic metabolism similar to those of humans. Over 40 years, Central Institute for Experimental Animals (CIEA) (President: Dr Tatsuji Nomura, MD) has devoted itself to maintain huge colony of CM so that individual animals share homogeneous genetic backgrounds. Under collaboration with CIEA, Keio University, genetically engineered CM is now being developed. Using NOG mice, for instance, the sensitivity of the human-derived cancer cells to anti-cancer reagents can be examined in vivo. To this end, recent advances of technology allow us to separate cancer and normal cells from the liver of a single mouse to discuss differences in molecular profiling and metabolic paradigm between the sites with and without cancer invasion.
Metabolome analysis combined with humanoid animals will give an evolutional impact on mining unknown regulatory mechanisms for human metabolism under normal and disease conditions. The analysis is an advanced high throughput technology that can quantitatively grasp a systematic profile of small-molecular metabolites. CE-(TOF)-MS is a powerful tool developed in Institute for Advanced Biosciences, Keio University. Metabolism is a dynamic process of life that determines repair, breakdown, and maintenance of cells and tissues in individual organisms. Thus, fluxome analyses, that is, in-vivo pulse chase of mass-labeled metabolites (e.g. 13C-glucose, 15N-13C-methionine, etc) under the disease conditions not only contribute to quantitative evaluation of the metabolites, but also determine velocities of multiple metabolic pathways that help us pin-point rate-limiting enzymes and uncover novel allosteric effectors responsible for the regulation. Until now, remarkable advances in genomic and proteomic technology such as genome-wide molecular analysis and methods to mine out protein-protein interaction (PPI) have led us to elucidate molecular mechanisms of human diseases and the stratagem to control the disease states at gene and protein levels is emerging. However, the lack of information on dynamics of metabolism is becoming another technical barrier to be broken through. Using advanced technology of metabolome and fluxome together with PPI analysis and computer-assisted informatics technology, our G-COE program aimes to promote humanoid metabolomics systems biology, and keeps challenging to reveal differences in metabolism among different intra-cellular or intra-organ compartments involved in host-parasite relationship.
Under G-COE, Keio University and universities abroad will carry out joint research and education projects at the graduate level in a bidirectional manner. From the Japanese side, predoctoral students will be dispatched for a period of up to 2 years to graduate schools oversea where they engage in research and education activities which will be counted towards their completion of the PhD program. Postdoctoral researchers and faculty members will also be exchanged between participating graduate schools in the two countries. In this way, the program aims to promote more systematic academic exchange between universities and graduate schools in the two countries, while contributing to fostering young researchers in doctoral programs and advancing international joint research. Based on the Japanese-developed cutting-edge technology called metabolome and humanoid animal creation technology, we will pioneer "human metabolomic systems biology" in collaboration with influential overseas proteomics centers and bio-defense/metabolic biology hubs which are at the center of vascular biology/energy metabolism research, and form a young researcher training and education research center.
4 clusters involved in this program are the following:
- Cluster for Humanoid animal models
- Cluster for Biodefense Metabolism
- Cluster for Cell Cycle, differentiation and metabolism
- Cluster for Metabolomic Networks
[G-COE FOREIGN PARTNERS]
(Core Collaborative Universities)
- Duke University School of Medicine, USA (Professor Peter C. Agre, Vice Chancellor, Duke University School of Medicine: Water Biology Initiative)
- Boston University School of Medicine, USA (Professor Richard A Cohen, Chief of Vascular Biology Unit and NIH Cardiovascular Proteomics Center, Boston University School of Medicine)
- Karolinska Institutet, Sweden (Professor Anita Aperia, Dept. of Pediatrics)
(Adjunctive Collaborative Universities)
- University of California Davis Graduate School, USA (Professor Fitz-Roy E. Curry, Associate Dean of Research, University of California School of Medicine)
- University of Pennsylvania (Professor Mark A Lemmon, Department of Biochemistry and Biophysics)
2. Objectives, needs/importance and prospective impacts of the COE establishment
As mentioned above, the field advocated by our G-COE is "human metabolomic systems biology". Previously, determination of metabolites is possible only by crushing cells and tissues; it is not possible to simultaneously determine the dynamics of multiple metabolic pathways in several compartments within the same individual animals or organisms. The metabolic characteristics of tumor-bearing tissues where healthy and cancerous cells coincide, or those in which the parasite/host interaction is established in vivo under infectious disease conditions, elucidation of mechanisms for metabolic remodeling and enzyme/protein interactions is obviously important to reveal new molecular targets for therapeutics. Exploring metabolism of hematopoietic and neural stem cells have been untouchable research areas in metabolomics to date because of a paucity of the cells available in population: However, such a problem can be thoroughly resolved by establishing the G-COE that systematically handle in-vitro-virus method (IVV), a novel PPI analyzing method developed by Professor Hiroshi Yanagawa, and advanced metabolome-fluxome analyzing devices with extremely high sensitivity. IVV is a powerful high throughput method that uncovers numerous PPI networks between different proteins by using only a small amounts of samples. On the other hand, pulse-chase analysis of mass-labeled metabolites (fluxome analysis) allows us to determine, for example, velocity of glycolysis or turnover of protein methylation through tracing a fate of the labeled methionine. Such methods benefit discovery of roles for metabolic regulation in determining stemness, proliferation and differentiation of progenitor cells and their relationship between specific phases of cell cycle.
Furthermore, the following methods will be employed at this center to advance metabolomic systems biology required for understanding and controlling human physiology/pathology: 1) establishment of humanoid mice where the host-parasite relation - which is not reproducible without human-based in vivo experiments- can be reconstituted. Functional analyses of metabolome-fluxome in human artificial chromosome transferred animals is another important example of the G-COE research activities, and; 2) application and promotion of overseas education and research collaborative institutions that have displayed (as mentioned above) basic technological developments needed for new in vivo metabolomic research, such as the development of mass-labeled incorporation analysis designed to systematically search for proteins targeted by mass-labeled low-molecular-weight molecules, and elucidate interaction-mediated bio-defense mechanisms. It is hoped that, by establishing this center, we will impart understanding of the dynamism and fascination of metabolic functions to young researchers in an international environment, and be able to intensively train graduate students to inspire to basic sciences in "human metabolomic biology" that converges a wide range of different areas.