Cellular membrane is the essential component of cells that distinguishes the inside and the outside of the cells. Each type of cell has a specific shape that is determined by the plasma membrane. The membrane receives every stimulus from cells, but its behavior is poorly understood. The support of the cytoskeleton determines the shape of the plasma membrane. Our lab will focus on the mechanisms connecting the membrane to the cytoskeleton. Our lab also focuses on the membrane-binding proteins connecting the membrane to the intracellular signaling for various cellular functions, including proliferation and morphological changes.
Elucidating cell-shape-dependent inter- and intra-cellular signaling
The intracellular signaling cascade became understood by observing molecule-molecule interactions. However, the spatial organization of these signaling cascades has not been studied so well. We found the BAR domain superfamily proteins that remodel membrane shape and then, presumably, dictate the intracellular signaling cascades.
The parts of the cells are released and delivered to the neighboring cells. These extracellular vesicles (exosomes and ectosomes) are also regulated by the BAR domain superfamily proteins.
Thus, the critical questions are how the BAR domain superfamily proteins are regulated and how they assemble the downstream molecules.
Searching for new membrane-binding proteins
Given the importance of membrane lipids as essential components of cells, we suppose many lipid-binding molecules have not been clarified. We are searching for novel lipid-binding proteins using a variety of methods.
The importance of fatty acids in the membrane.
Another point for understanding the cellular membrane is the importance of the fatty-acid tails of lipids. Although the importance of saturated or unsaturated lipids in nutrients is well-known, the mechanism of importance is not understood at molecular levels in cell biology. We will examine how fatty acids are essential in intracellular signaling, including that for cancer, using the proteins listed above.