Please read the top page, too. The following are more details.
Membrane and the Cytoskeleton
Each cell type has a specific shape determined by the plasma membrane.
The shape of the plasma membrane is determined by the support of the cytoskeleton. Our lab will focus on the mechanisms connecting the membrane to the cytoskeleton.
The responsible molecules are the “interface” between the membrane and the cytoskeleton, which may be indispensable for the special “shape” of each cell type.
We are currently focusing on the proteins that connect the membrane and cytoskeleton. These proteins include FBP17, Toca-1, syndapin, and IRSp53.
Press Release Articles: 2019, 2021-1, 2021-2, Journal interview 2020, First Author Interview.
Elucidating cell-shape dependent inter/intracellular signaling
We understood the intracellular signaling cascade by observing molecule-molecule interactions. However, the spatial organization of these signaling cascades has not been well studied. We found that BAR domain superfamily proteins remodel membrane shape and, presumably, dictate intracellular signaling cascades. Thus, key questions remain: how are BAR domain superfamily proteins regulated, and how do they assemble downstream molecules?
The extracellular vesicles
The BAR domains are involved in membrane invaginations for clathrin-coated pits, caveolae, and so on. These invaginations are pinched off to form endocytic vesicles. The I-BAR domains are involved in the membrane protrusions for filopodia and microvilli. These protrusions are also found to be pinched off to form extracellular vesicles (EVs). EVs can transmit materials between cells and mediate intercellular communication in every biological phenomenon, including senescence, cancer onset and progression, as well as differentiation.
Searching for new membrane-binding proteins
Given the importance of membrane lipids as essential components of cells, we suppose there are many lipid-binding molecules that 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 key point in understanding the cellular membrane is the importance of lipid fatty-acid tails. Although the importance of saturated or unsaturated lipids in nutrients is well-known, the mechanism of their importance is not understood at the molecular level in cell biology. We will examine how fatty acids are important in intracellular signaling, including that for cancer, using the proteins listed above.
Press Release Articles: 2019, 2021-1, Journal interview 2020, First Author Interview.
Application of data science to cell biology.
The above complexity of proteins and lipids results in complex cell morphology. The complex cell morphology can be divided into subcellular structures, which can be described using proteins and lipids. To understand such complexity and the connectivity between subcellular structures, we will cross-correlate the localizations of the proteins and the lipid membrane in space and time by using information technologies, including deep learning. The expected results will complement the above research and also predict the behavior of the cells.
Press Release Articles: 2021-2