Prof. Keiko Torii University of Texas / HHMI

Prof. Tian Xu Westlake University

July 17, 2025, 17:05-17:55, Room A

[PL-01]
Intertwined regulation of cell cycle and cell fate during developmental patterning of plant epidermis

Prof. Keiko U. Torii

[Abstract]

During the development of multicellular organisms, each cell must interpret complex, conflicting signals to make a decision that translates into functional tissues critical for organismal fitness. Due to the presence of the cell walls, morphogenesis of the plants occurs in the absence of cell migration and relies on cell-cell communication, cell division, as well as cellular mechanics and morphogenesis. Focusing on the developmental patterning of plant stomata, adjustable valves on the land plant epidermis for efficient gas exchange and water control, we aim to uncover a governing principles of cell-cell communication and cell fate specification. Our recent study uncovered the mechanism by which the 'master-regulatory' transcription factors precisely instruct the cell-state transition events within the stomatal lineages. Furthermore, we revealed how these transcription factors interplay with cell cycle machineries to specify a switch from proliferative asymmetric divisions to a single, terminal symmetric division that creates paired guard cells. Through chemical-genetics and live-imaging approaches, we show that proper cell cycle checkpoints are critical for properly segregating stomatal and non-stomatal epiderma cell fates. Stomata are the key developmental innovation of land plants vital for their growth and survival. As such, fundamental knowledge gained from my research will impact our health and sustenance. 

 

July 17, 2025, 17:55-18:45, Room A

[PL-02]
Biological Quantifications in Development, Neural Behaviors, and Medicine

Prof. Tian Xu

[Abstract]

Quantification is essential for both dvelopement and neural behavior. Our past efforts of genetic dissection in Drosphila identified key mechanisms for regulation of tissue size and growth in development and diseases, including the conserved Lats/Hippo and AKT/TSC/TOR pathways. However, the neural mechanisms for quantity discrimination of external matters remain elusive. Here, we report the eslabilsment of a mouse model for quantifying different amounts of food, which is similar to human behavior, following the Weber-Fechner Law. Both viral inhibition experiments in mice and surgery data in patients have identified the specific cortex region involved in quantity discrimination behavior. Two-photon imaging of neuronal activities revealed that quantity discrimination is not coded by selected neurons with preferential activities or the number neurons. Instead,  the synchronous firing patterns of the neuronal population correlate quantity discrimination behaviors. Following Shannon’s Entropy for information and computer science, we propose a Neural Entropy model, which could predict quantity quantity discrimination. Our study has not only provided a new biological quantification system key to human and animal survival, but also has significant implications for AI. Finally, we have developed AI models to quantify transcriptomic data in diseases, drugs, and herbal medicine and predicted potential therapies in clinical trials.