Tsuyoshi Sakai, Phd

Tsuyoshi Sakai, PhD

Assistant Professor
School of Medical Biological Sciences
Phone: 903-877-7224

Dr. Sakai is working on the function and regulation of the motor protein, myosin, in diverse cellular motile processes, such as muscle contraction, cell division, intracellular trafficking, cell locomotion, endocytosis, phagocytosis, epithelial sheet closure in development, wound healing, neuronal path finding, immune cell function, cell invasion, metastasis of cancer cells and vesicle transport. The malfunction of these myosins causes various diseases, such as cardiac myosin II for human cardiomyopathy, myosin VIIA for human deafness and blindness, myosin IIIA, VI and XV for nonsyndromic hearing loss, myosin VI for neurodegenerative diseases such as Alzheimer's.

Myosin Va for Griscelli disease, which is characterized by neurologic impairment and severe nervous system dysfunction, and cancer invasion and metastasis for myosin X. In order to treat these diseases, it is necessary to clarify the molecular mechanism of each myosin-based motility event. Recent progress of myosin research has raised a hypothesis that each myosin has unique motor characteristics, specific docking partners and is differently regulated to achieve a specific cellular function. Yet the physiological function and regulation of these motor proteins are far from understood.

Dr. Sakai’s concept is that the binding partner may not only be a passive cargo, but also affect the mechanoenzymatic activity and single-headed/two-headed transition of motor proteins. His research is geared towards developing a more clear understanding of those functions.

Education and Training

Soka University in Japan, M. Eng., 1996, Molecular biology
Soka University in Japan, Ph. D., 2008, Molecular biology
University of Massachusetts Medical School, Postdoc, 2011, Physiology

Courses Taught

Molecular Biology, Methods for introducing mutations.
Protein purification, Yeast two hybrids.

Research Interests

Function and regulation of unconventional myosin.
Visualization of moving molecules within living cells.

Publication Highlights

He, K., Sakai, T., Tsukasaki, Y., Watanabe, T. M., & Ikebe, M. (2017). Myosin X is recruited to nascent focal adhesions at the leading edge and induces multi-cycle filopodial elongation. Sci Rep, 7(1), 13685. doi: 10.1038/s41598-017-06147-610.
Sakai, T., Jung, H. S., Sato, O., Yamada, M. D., You, D. J., Ikebe, R., & Ikebe, M. (2015). Structure and Regulation of the Movement of Human Myosin VIIA. J Biol Chem, 290(28), 17587-17598. doi: 10.1074/jbc.M114.599365.
Sakai, T., Umeki, N., Ikebe, R., & Ikebe, M. (2011). Cargo binding activates myosin VIIA motor function in cells. Proc Natl Acad Sci U S A, 108(17), 7028-7033. doi: 10.1073/pnas.1009188108.