Formation mecahnisms of 3-dimensional tubular structure like seminiferouos tubules in culture system

2003 Fiscal Year Final Research Report Summary

• Project/Area Number: 14570020
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: General anatomy (including Histology/Embryology)
• Research Institution: Yokohama City Universituy
• Principal Investigator: OBATA Shuichi Yokohama City University, Medicine, Associate Prof., 医学部, 講師 (10204273)
• Co-Investigator(Kenkyū-buntansha): SAWADA Hajime Yokohama City University, Medicine, Prof., 大学院医学研究科, 教授 (90101112) ; ONO Michio Yokohama City University, Medicine, Assistant Prof, 医学部, 助手 (50264601) ; YAZAMA Futoshi Hiroshima Prefectural University, Biological Resources, Associate Prof., 生物資源学部, 助教授 (00254160)
• Project Period (FY): 2002 – 2003
• Keywords: cell adhesion / cytoskeleton / cadherin / catenin / actin / integrin

Research Abstract

To understand the mechanisms of 3-dimensional tubular structure formation, we investigated cell-cell adhesion structure formation and cell-extracellular matrix adhesion structure formation by using several cell biological techniques. The peripheral region of one MDCK cell overlapped the peripheral of the neighboring cell with large area. In this overlapped area, lots of punctual fluorescent signals derived from E-cadherin were observed. The mean value of equivalent radius of the E-cadherin puncta was about 200nm. Based on the calcium-switch experiments, typical E-cadherin puncta were formed in early period from the recovery of calcium deletion. Ninety minuets after the addition of the external calcium, linear E-cadherin staining pattern aligning several puncta was also observed. When the cells were treated with cytochalasin D or jasplakinolide, typical E-cadherin punctual pattern were clearly changed. α-catenin, β-catenin, γ-catenin, and p 120ctn were colocalized at the E-cadherin puncta. To understand the biological roles of mechanical environment on tubular structure formation by using ST2 cells cultured on polyacrylamide gels. The cells cultured on harder scaffold (gel) extended well, and contained many large focal adhesion and thick stress fibers. In contrast, the cell areas were small, the focal adhesion and the stress fibers were also tiny in the the cells cultured on soft scaffold. Phosphorylation level of the focal adhesion was reduced in the cells on the soft scaffold. The kind of proteins which was contained at the focal adhesion was not changed.