interests = My research interests are the mechanism of cell polarity and cell migration. The direction of cell polarity or migration is determined by the symmetry breaking of Ras-GTP, which is self-organized by the excitable system. This accumulation of Ras-GTP regulates the downstream cytoskeletal system and drives cell migration. And, Ras is a key factor in signal cascade and regulates a lot of molecules involved in cell polarity and migration. Therefore, it is important to reveal the regulatory mechanism of Ras activation. Now, I research the GEFs involved in Ras activation to reveal my problem.