Analysis of mechanism involved in cell-cell junction formation using Drosophila as a model system

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K07048
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Cell biology
• Research Institution: National Institute for Physiological Sciences
• Principal Investigator: Izumi Yasushi 生理学研究所, 生体機能調節研究領域, 准教授 (10373268)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 上皮細胞 / 細胞間接着装置 / 細胞間隙バリア / ショウジョウバエ / 閉塞結合 / セプテートジャンクション

Outline of Final Research Achievements

Smooth septate junctions (sSJs) are cell-cell junctions that regulate the paracellular pathway of the endodermally-derived epithelial cells in arthropods. Previously, we identified Ssk and Mesh as specific components of sSJs in Drosophila. To understand the molecular mechanisms involved in sSJ formation, we carried out a genetic screen of a Drosophila chromosomal deficiency stock and identified several strains defective in the localization of Mesh at sSJs. By analyzing these strains, we found that the genes encoding tetraspanin, Tsp2A and a novel single membrane-spanning protein, CG13704 were responsible for the phenotype. Both proteins specifically localized at sSJs and were required for sSJ formation as well as the barrier function of the midgut. Furthermore, we found that Tsp2A, CG13704, Ssk and Mesh form a complex and were interdependent for their sSJ localization. Therefore, we concluded that these sSJ-proteins act together to organize sSJs.

Free Research Field

細胞生物学