Abstract
Vacuoles have diverse functions within all plant cells. Vacuoles get rid of wastes, accumulate nutrients, and regulate pressure within a cell. They are also known to store sugars. However, only a small number of vacuolar sugar transporters have been identified and characterized.
We first identified a vacuolar sucrose transporter from tobacco BY-2 cells (NtSUT4) and established transgenic tobacco BY-2 cells that overexpress NtSUT4-GFP (BY-SUTG cells). Using model system for synchronous cell elongation in miniprotoplasts (evacuolated cells) prepared from tobacco BY-2 cells, we found that overexpression of NtSUT4-GFP inhibit cell growth towards cell major axis. Moreover, in the same condition, we also found that, in BY-SUTG cells, more amount of cellulose accumulated than in wild type BY-2 cells. These results suggest that NtSUT4 affects cell wall formation and involved in cell shape via sucrose homeostasis in plant cells.
