Analysis of ER membrane proteins in ER dynamics

2015 Fiscal Year Final Research Report

• Project/Area Number: 25440132
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Plant molecular biology/Plant physiology
• Research Institution: Kyoto University
• Principal Investigator: Ueda Haruko 京都大学, 理学(系)研究科(研究院), 研究員 (90402776)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 小胞体 / 原形質流動 / 膜融合

Outline of Final Research Achievements

The endoplasmic reticulum (ER) is the organelle with the largest membrane surface area in eukaryotic cells. The ER membrane is physically continuous and extends throughout the cytoplasm. A striking feature of the plant ER is the active streaming driven by plant-specific class XI myosins. We found that the ER streaming was suppressed in root hair defective (rhd3) mutants. RHD3 is a membrane-associated dynamin-like GTPase. A deficiency of RHD3 caused a defect in the interconnection of the membranes, resulting in the occurrence of many ER fragments in the rhd3 cells. In addition, the ER network is RHD3-dependently reconstituted from the cytosol and microsome fraction of tobacco cultured cells by exogenously adding GTP, ATP, and F-actin. These results indicate that RHD3 functions as an ER membrane fusogen in plants. The fusogenic activity of RHD3 may contribute to the smooth movement of the ER.

Free Research Field

植物細胞生物学