Mechanical interactions between the ECM and cells are essential for biological phenomena involving three-dimensional structural changes in three-dimensional tissues and organs, such as embryogenesis and cancer. In order to elucidate such mechanical interactions between cells and the ECM inside three-dimensional tissues, this project group will develop a research method that combines an original mathematical model that enables integrated analysis of the three-dimensional dynamics of the ECM and multicell with mechanical measurements inside three-dimensional tissues. In addition to the mechanical interaction, we will develop an "ECM-multicellular integrated model" by incorporating biochemical interactions based on omics data analysis (A03 Shimamura) into the mathematical model. The developed model will be applied to skin follicles and mammary glands (A01 Fujiwara), vascular tissue (A02 Yamashiro), and organoids (A02 Eiraku) to elucidate the mechanisms of organogenesis. Furthermore, we will try to understand the control mechanism of multimodal information of ECM by changing various parameters of ECM included in the mathematical model on the mathematical model. In addition, we aim to predict the dynamics of stem cell organoids (A02Eiraku) by combining the technology developed here with perturbation experiments of multicellular dynamics using hydrogel (A02 Narutaki).