| 1. |
Coordination of FGF and Wnt in the construction of the hierarchical branching structure of lung. |
| 2. |
今村寿子, 平野朋子, 佐藤雅彦, Mathematical model of the plant root hair morphogenesis depending on the cell wall hardening, 第53回日本発生生物学会年会, 2020.05. |
| 3. |
今村寿子, Observation of FGF response in lung epithelium and modeling for
branching morphogenesis, 新学術領域研究「上皮管腔組織形成」第２回国際シンポジウム, 2015.08, The differences in cellular behavior underlying morphogenesis are governed by signaling interactions in the growing tissue. In lung branching morphogenesis, for instance, the high sensitivity of cells to the distribution of diffusive signals within the developing tissue is considered to be the principle mechanism guiding shape change. Here I investigated the response and sensitivity of lung epithelium to FGF10 that mediates epithelial branching to realize the tissue-specific shape. I demonstrated that uptake of FGF10 by epithelial explants of the pseudoglandular stage lung in Matrigel was sensitive over a wide range of FGF10 concentrations in the gel. It was also indicated that MAP kinase activity downstream of FGF10 was affected by the epithelial explant size and shape as well as the FGF10 concentration. These cellular responses of lung epithelium to FGF10 were higher in E13 than E14. To assess how these cellular responses result in shape formation of the lung epithelium, I constructed a framework employing a mathematical model in which an epithelial tip splits depending on the proliferative and chemotactic activities. Experimental results on lung epithelium were incorporated into the model and how the ordered structure of lung emerges will be discussed.. |
| 4. |
Takigawa-Imamura H, Kutsuna N, Higaki T, Akita K, 三浦 岳, Jigsaw Puzzle Pattern in the Epidermal Cell Wall of Leaves, The 62nd NIBB Conference, 2014.11, The epidermal cells on leaves are gradually deformed into jigsaw-puzzle shapes as they develop. Here, we theoretically examined the possibility of the mechanical buckling as the underlying mechanisms that the plant cell wall is curved. We considered the disproportion between the cell wall (surface area) and cytosol (volume) generates mechanical force to restore the stability of shape, and the buckling of the cell wall will resolve the unbalance in the surface-volume ratio. To depict this concept in the growth process, we constructed a plant cell model where the lateral cell wall was described as an elastic sheet. The model showed the formation of jigsaw puzzle shapes in each cell depending on the ratio of the wall growth relative to the cytosolic growth of cells. We analyzed this result by comparing to the actual pattern on the plant leaf, which shows various cell sizes and shape characteristics. The pattern changes seen in chemical exposure experiments were explained in terms of its possible effect on the physical property of the walls by this model. It was also examined how the heterogeneity of the bending elasticity in the cell wall affect the wavelength of curvature. Our model provides the simple working hypothesis for the spontaneous generation of complicated pattern in plant epidermal cells.. |
| 5. |
今村 寿子, 三浦 岳, 朽名夏麿, 桧垣匠, 秋田佳恵, Jigsaw puzzle pattern in the epidermal cell wall of leaves, The Joint Annual Meeting of the Japanese Society for Mathematical Biology and the Society for Mathematical Biology, Osaka 2014, 2014.07, The epidermal cells on leaves are gradually deformed into jigsaw-puzzle shapes as they develop. Here, we theoretically examined the possibility of the mechanical buckling as the underlying mechanisms that the plant cell wall is curved. We considered the disproportion between the cell wall (surface area) and cytosol (volume) generates mechanical force to restore the stability of shape, and the buckling of the cell wall will resolve the unbalance in the surface-volume ratio. To depict this concept in the growth process, we constructed a plant cell model where the cell wall was described as an elastic sheet. The model showed the formation of jigsaw puzzle shapes in each cell depending on the ratio of the wall growth relative to the cytosolic growth of cells. We analyzed this result by comparing to the actual pattern on the plant leaf, which shows various cell sizes and shape characteristics. The pattern changes seen in chemical exposure experiments were explained in terms of its possible effect on the physical property of the walls by this model. It was also examined how the heterogeneity of the bending elasticity in the cell wall affect the wavelength of curvature. Our model provides the simple working hypothesis for the spontaneous generation of complicated pattern in plant epidermal cells.. |
