Speaker: Hironobu Fujiwara (Team Director, Center for Biosystems Dynamics Research, RIKEN）

Title: coming soon

Date&Time: 25 November (wed)　12：00-13：00

Venue: Conference Room(1F), IMEG, Kumamoto University  On site + Zoom

※This seminar can also be attended through ZOOM. Please check the URL on “S-HIGO Cutting-Edge Seminar A, B” at Moodle.

https://md.kumamoto-u.ac.jp/course/view.php?id=136783

Abstract:

coming soon

Speaker: Shizu Aikawa (Associate Professor, Life Science Center of Tsukuba Advanced Research Alliance, University of Tsukuba）

Title: The Decidua: A Foundation for Successful Pregnancy

Date&Time: 11 November (wed)　12：00-13：00

Venue: Zoom only

※This seminar can also be attended through ZOOM. Please check the URL on “S-HIGO Cutting-Edge Seminar A, B” at Moodle.

https://md.kumamoto-u.ac.jp/course/view.php?id=136783

Abstract:

Embryo implantation represents the first critical step in the interaction between the embryo and the maternal uterus. Defects in this process can lead to pregnancy loss and placental disorders. Successful pregnancy requires not only embryo attachment but also the formation of a specialized maternal environment, known as the decidua, that supports subsequent embryonic development. Our research has focused on elucidating the molecular mechanisms underlying decidual formation and its physiological functions during pregnancy. Recent studies have revealed critical roles of extracellular matrix remodeling in regulating trophoblast invasion and decidual development, highlighting the importance of HIF2α–LOX signaling and the Hippo pathway effector TAZ. In this seminar, I will present our recent findings on how the maternal decidual microenvironment is established and how it contributes to successful pregnancy.

Speaker: Leqian Yu (Professor, Institute of Zoology, Chinese Academy of Sciences)

Title: Embryo 3D reconstruction and embryo models: get a glimpse of the human gastrulation

Date&Time: 4 November (wed)　12：00-13：00

Venue: Zoom only

※This seminar can also be attended through ZOOM. Please check the URL on “S-HIGO Cutting-Edge Seminar A, B” at Moodle.

https://md.kumamoto-u.ac.jp/course/view.php?id=136783

Abstract:

The extreme scarcity of human embryo samples, combined with the significant differences between traditional model organisms, such as mice, and human early development, results in limited understanding of human embryonic development, particularly from implantation to gastrulation. This has led to what is referred to as the developmental “black box.” Stem cell-based embryo models offer a potential solution for exploring developmental events during this period. However, challenges remain in model development. Our study focuses on two key areas: 1) creating a developmental blueprint through 3D digital reconstruction of human embryos, and 2) simulating the developmental environment by constructing an artificial uterus system. These efforts aim to optimize the creation and development of embryo models, thereby enhancing our understanding of human early development.

Cell 2026, 2025, 2024, 2023,
Nature 2021, Cell Stem Cell 2025, 2023, 2020
http://english.ioz.cas.cn/staff/en/leqianyu.html

Speaker: Shinichiro Akichika (Project Research Associate, Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo)

Title: Transfer RNA modification is a major determinant to coordinate mRNA stability, proteostasis, and longevity

Date&Time: 28 October (wed)　12：00-13：00

Venue: Conference Room(1F), IMEG, Kumamoto University  On site + Zoom

※This seminar can also be attended through ZOOM. Please check the URL on “S-HIGO Cutting-Edge Seminar A, B” at Moodle.

https://md.kumamoto-u.ac.jp/course/view.php?id=136783

Abstract:

Transfer RNAs (tRNAs) harbor diverse post-transcriptional modifications that are essential for maintaining the accuracy and efficiency of protein synthesis. Here, we identify MTL-A and MTL-B as previously uncharacterized human tRNA methyltransferases responsible for 2ʹ-O-methylation at position 39 (Nm39) in cytoplasmic tRNAs, and show that each enzyme selectively modifies distinct tRNA substrates. Analysis of MTL-A/B double-knockout cells revealed that Nm39 regulates ribosome elongation dynamics at specific codons and is required to maintain the stability of mRNAs enriched with optimal codons. Consistent with this, codon stability coefficients (CSCs) determined from transcriptome-wide mRNA half-lives were extensively reorganized in the double knockout cells, resulting in a global reversal of the codon optimality landscape across virtually all sense codons in human cells. These findings demonstrate that Nm39 not only modulates translation elongation at individual codons but also serves as a key molecular determinant of codon optimality. Furthermore, Nm39 promotes co-translational protein folding, thereby contributing to proteostasis. The double-knockout cells exhibited increased sensitivity to iron deficiency but enhanced resistance to oxidative stress. In Drosophila melanogaster, loss of Mtl-A significantly shortened lifespan, whereas its overexpression extended lifespan, indicating that Nm39 also contributes to organismal longevity. Collectively, our findings not only elucidate Nm39 biogenesis but also demonstrate that codon optimality is not a static property encoded in the genome, but a dynamic feature established by tRNA modification. More broadly, we identify Nm39 as an epitranscriptomic regulator that coordinates mRNA stability, translational control, proteostasis, and aging through the establishment of codon optimality.

Speaker: Yuta Matsuoka (Associate Professor, Center for Cancer Immunotherapy and Immunobiology, Kyoto University)

Title: “From Bodily Odor to Molecular Diagnosis”

Date&Time: 14 October (wed)　12：00-13：00

Venue: Conference Room(1F), IMEG, Kumamoto University  On site + Zoom

※This seminar can also be attended through ZOOM. Please check the URL on “S-HIGO Cutting-Edge Seminar A, B” at Moodle.

https://md.kumamoto-u.ac.jp/course/view.php?id=136783

Abstract:

The relationship between human odor and disease has long attracted attention. The molecular basis of such odors is volatile organic compounds (VOCs) released from the body. VOCs are low-molecular-weight organic compounds generated through diverse metabolic reactions and emitted as breath or skin gas via alveolar capillaries and sebaceous glands. Because disease onset is accompanied by alterations in systemic metabolism, disease-specific VOC profiles may provide valuable non-invasive biomarkers.
However, VOCs are highly susceptible to loss during sampling and analysis, as well as contamination from exogenous compounds. Therefore, dedicated analytical platforms distinct from those used for conventional liquid-phase metabolites are required.

To address these challenges, we have developed mass spectrometry-based technologies for sensitive VOC analysis and applied multiscale approaches spanning molecules, cells, animals, and humans. Through these efforts, we aim to establish disease metabolism monitoring strategies based on bio-gas VOC profiling.
Recently, we identified volatile oxidized lipids as biomarkers for non-invasive detection of lipid peroxidation and ferroptosis in vivo, and advanced their clinical application[1]. In this lecture, I will introduce our recent progress in developing technologies to detect disease-associated metabolic alterations through body odor.

Speaker: Takayoshi Suganami (Professor, Nagoya University, Research Institute of Environmental Medicine)

Title: Immunometabolism and Lifestyle-Related Diseases: Bridging Metabolism and Inflammation

Date&Time: 7 October (wed)　12：00-13：00

Venue: Zoom only

※This seminar can also be attended through ZOOM. Please check the URL on “S-HIGO Cutting-Edge Seminar A, B” at Moodle.

https://md.kumamoto-u.ac.jp/course/view.php?id=136783

Abstract:

Lifestyle-related diseases such as obesity and diabetes have been regarded as metabolic disorders, and extensive research has focused on whole-organ gene expression profiles, metabolic functions, and hormone production. However, it has become increasingly clear that lifestyle-related diseases also have features of chronic inflammatory diseases, highlighting the need to reconsider their pathophysiology from the perspective of chronic inflammation. For example, in adipose tissue, overnutrition induces dynamic tissue remodeling, including adipocyte hypertrophy, immune cell infiltration, angiogenesis, and excessive extracellular matrix deposition. These changes impair adipose tissue functions, such as lipid storage and adipokine production, leading to the spread of metabolic abnormalities throughout the body.

Meanwhile, in immunology, increasing attention has been paid to how intracellular metabolism regulates immune cell functions. These findings have revealed a close relationship between nutrition, metabolism, inflammation, and immunity, leading to the emergence of the research field of immunometabolism.

We have focused particularly on the molecular mechanisms by which metabolic stress-induced cell death promotes chronic inflammation and have identified common pathological mechanisms in obesity, metabolic dysfunction-associated steatohepatitis (MASH), and chronic kidney disease. In this lecture, I will discuss the complex regulation of immunometabolism at the organismal, organ, and cellular levels, and its significance in lifestyle-related diseases, with a focus on our recent research findings.

Speaker: Hirohisa Kyogoku (Associate Professor, Graduate School of Agricultural Science, Kobe University)

Title: From Oocytes to Early Embryos: Specialized Cell Division Strategies for Maintaining Genome Stability

Date&Time: 30 September (wed)　12：00-13：00

Venue: Conference Room(1F), IMEG, Kumamoto University  On site + Zoom

※This seminar can also be attended through ZOOM. Please check the URL on “S-HIGO Cutting-Edge Seminar A, B” at Moodle.

https://md.kumamoto-u.ac.jp/course/view.php?id=136783

Abstract:

Early mammalian development is characterized by a series of rapid cell divisions that occur without accompanying cell growth. Oocytes and zygotes possess exceptionally large cytoplasmic volumes, containing abundant maternal factors that support early embryogenesis. These unique cellular environments raise a fundamental question: do oocytes and early embryos employ the same mechanisms of cell division and genome maintenance as somatic cells?

In this seminar, I will present our recent studies revealing stage-specific strategies that safeguard genome integrity during early mammalian development. First, I will describe how the exceptionally large cytoplasmic volume of oocytes compromises spindle stability and spindle assembly checkpoint (SAC) efficiency, thereby increasing the risk of chromosome segregation errors. Next, I will introduce our recent finding that the two parental pronuclei in the zygote compete for limiting cytoplasmic factors required for nuclear assembly, thereby regulating pronuclear size, epigenetic state, and developmental potential. Finally, I will discuss how the DNA replication timing program is progressively established during preimplantation development, and how its emergence is closely associated with replication stress and genome instability.

Together, these studies demonstrate that oocytes and early embryos employ specialized cell division strategies that differ fundamentally from those of somatic cells. By integrating live-cell imaging with single-cell genomic and epigenomic approaches, our work provides new insights into the mechanisms that preserve genome integrity during the earliest stages of mammalian life.

Speaker: Toshiro Hara (Assistant Professor, University of Michigan, Medical School)

Title: Decoding Brain Cancer Ecosystem in Humans: From Complexity to Mechanism

Date&Time: 16 September (wed)　12：00-13：00

Venue: Zoom only

※This seminar can also be attended through ZOOM. Please check the URL on “S-HIGO Cutting-Edge Seminar A, B” at Moodle.

https://md.kumamoto-u.ac.jp/course/view.php?id=136783

Abstract:

Glioblastoma is an incurable form of brain tumor. It is a community of diverse tumor cells that share brain space for their growth and invasion, engaging in a variety of cellular communications, from tumor-immune interactions to tumor-brain structure interactions. Understanding the intricacies might help us to urge improvements in therapies and outcomes for patients. We characterized human tumors and model systems by single-cell expression profiling and spatial analysis and found that glioblastoma is dominated by a limited set of four tumor subpopulations. Our subsequent work to dissect glioblastoma-microenvironment interactions revealed that macrophages are the major immune infiltrate and induce mesenchymal phenotypes, one of the four states, in glioblastoma cells. Further, we experimentally demonstrated that the mesenchymal state in glioblastoma is associated with cytotoxic T-cell programs. As a tool for probing the function and dynamics of tumor subpopulations, we adapted patient-derived xenografts (PDX) for pooling in multiplexed assays and examined the geographically diffusive nature of glioblastoma at the single-cell level. With models capable of invading along the periphery of neurons or blood vessels, our analysis revealed the ability of glioblastoma cells to change their phenotypes in response to environmental changes. Collectively, our studies lead to new insights into the effect of cell-cell interactions on intratumoral heterogeneity and response to therapies.

Speaker: Tomoya Kitajima (RIKEN Center for Biosystems Dynamics Research)

Title: Understanding and preventing age-associated chromosome segregation errors in oocytes

Date&Time: 2 September (wed)　12：00-13：00

Venue: Conference Room(1F), IMEG, Kumamoto University  On site + Zoom

※This seminar can also be attended through ZOOM. Please check the URL on “S-HIGO Cutting-Edge Seminar A, B” at Moodle.

https://md.kumamoto-u.ac.jp/course/view.php?id=136783

Abstract:

Egg aneuploidy is a leading cause of miscarriage and congenital disorders such as Down syndrome. It arises from chromosome segregation errors during oocyte meiosis, with incidence increasing markedly with maternal age. However, the oocyte-intrinsic features and age-associated defects that promote these errors remain incompletely understood.

Using mouse oocytes as a model, we investigate chromosome dynamics and the cellular machinery driving meiotic chromosome segregation, including the spindle and kinetochores. We have identified multiple oocyte-intrinsic factors that predispose oocytes to segregation errors, including (1) mechanisms governing spindle bipolarization and (2) regulation of kinetochore–microtubule attachments. In addition, we have found that (3) premature chromosome separation represents a major age-associated defect. In this talk, I will present our recent findings on the cell biological basis of chromosome segregation errors in oocytes and discuss emerging error-prevention strategies using synthetic tools currently under development.

Speaker: Kaori Kuribayashi-Shigetomi (Associate Professor, Institute for Academic Innovation Educational Research Division, Hokkaido University)

Title: Micro/Nano Engineering for 3D Tumor Models and Tumor Calcification: From Biomimetic Cancer Models to a New Therapeutic Concept

Date&Time: 29 July (wed)　12：00-13：00 Cancelled

Venue: Conference Room(1F), IMEG, Kumamoto University  On site + Zoom

※This seminar can also be attended through ZOOM. Please check the URL on “S-HIGO Cutting-Edge Seminar A, B” at Moodle.

https://md.kumamoto-u.ac.jp/course/view.php?id=136783

Abstract:

Three-dimensional (3D) cell culture has become an indispensable platform for studying cell biology, cancer progression, drug discovery, tissue engineering, and regenerative medicine. In this seminar, I will introduce our micro/nanoengineering approaches for constructing biomimetic 3D tissues and discuss their application to understanding tumor biology and developing future therapeutic strategies.

First, we developed a self-folding technique, termed “cell origami”, that exploits cell traction forces (CTFs) to transform two-dimensional microfabricated plates into 3D cell-laden microstructures. Unlike conventional microfabrication approaches requiring external actuation, cell origami utilizes intrinsic cellular forces to achieve spontaneous folding, enabling the rapid fabrication of diverse 3D tissue architectures by simply designing the geometry of microplates and hinges.

Second, we established a micro/nanopatterned culture platform that enables cancer cells to spontaneously organize into 3D microtumors exhibiting cell-in-cell (entosis-like) structures, closely resembling invasive tumor lesions observed in pathological tissues. The platform allows real-time observation of tumor morphogenesis and reveals distinct growth and invasive behaviors depending on cancer malignancy, providing a powerful in vitro model for cancer research and drug screening.

Finally, I will present our recent discovery that these engineered pancreatic tumor tissues undergo localized tumor calcification. Live-cell imaging revealed that dead-cell debris generated within the tumors accumulates on the tumor surface, where phospholipid-rich membrane fragments serve as nucleation sites for calcium crystal formation. This biomimetic tumor-on-a-chip platform provides a unique opportunity to investigate the mechanisms of pathological calcification and may open a new therapeutic concept of “turning tumors into stone” by promoting tumor-specific calcification.

Abstract.pdf