Structure and function of the zipper-like structure

2015 Fiscal Year Final Research Report

• Project/Area Number: 25462873
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Morphological basic dentistry
• Research Institution: Showa University
• Principal Investigator: Takito Jiro 昭和大学, 歯学部, 助教 (00197237)
• Co-Investigator(Renkei-kenkyūsha): NAKAMURA Masanori 昭和大学, 歯学部, 教授 (50180394)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 破骨細胞 / 細胞骨格 / 細胞内小器官 / 細胞融合 / 細胞接着

Outline of Final Research Achievements

Osteoclasts are multinucleated giant cells that resorb bone. We previously reported that the podosome belt transforms into another superstructure, called the zipper-like structure (ZLS), at the cell contact site of two osteoclasts. To assess the role the ZLS in osteoclast fusion, we examined the static and dynamic dynamic structure of the ZLS in the osteoclast-like cells differentiated from RAW 264.7 cells. Immunofluorescence showed that the transformation of the podosome belt into the ZLS was associated with a rearrangement of component proteins. Live-cell imaging using EGFP-actin showed that the ZLS exhibited consistent symmetrical retrograde actin flow. We next examined signaling network that forms or maintains the ZLS. M-CSF, Rac1, Src and dynamin were positive regulators of the ZLS formation, whereas RhoA was a negative regulator. These molecules also affect osteoclast multinucleation. Thus, we concluded that the ZLS was positively involved in osteoclast fusion.

Free Research Field

細胞生物学