[Visualization of actin cytoskeleton in living cells of Torenia fourineri using GFP-mTn fusion protein].

Abstract

By transformation mediated by Agrobacterium tumefacien, we successfully transferred the chimeric gene of GFP-mTn ( mTn is the binding domain of microfilament binding protein talin from mouse, which can show the microfilament in living cell ) into Torenia fournieri. Using confocal laser scanning microscopy (CLSM), the distribution of fusion protein in different kinds of tissues and cell in transgenic Torenia fournieri was observed. GFP fluorescence was found in leaf epidermal cell, stomatal guard cell and root epidermal cell. Actin filaments can be visualized clearly only in guard cells. In the guard cells of open stomata under light, actin filaments arrange reticularly and randomly in cortical cytoplasm. In the guard cells of closed stomata under darkness, actin filaments arrange curly along the longitude of guard cell, and some helix and ring structures were found. GFP fluorescence was not found in other cell types, including stem epidermal cell, root hair cell and reproductive organs. The transgenic Torenia fournieri we got provides a suitable material to study dynamics of actin filament in stomatal guard cell.