Hiroshi Tokuo, M.D., Ph.D.
Research Scientist
myosin, cytoskeleton, lamellipodia, filopodia
Email: tokuo at bbri.org

Research Summary
During cell migration, the protrusive leading edge plays a key role in directional movement. The leading edge of migrating cells consists of two types of actin cytoskeletal architecture, lamellipodia and filopodia. Our research interest is the mechanism of unconventional myosins in cytoskeletal dynamics, i.e., lamellipodial localization of myosin-I, and filopodia formation by myosin-X. We use a combination of biochemical and molecular techniques, immunocytochemistry, and live cell-imaging techniques. Our goal is to understand a broad range of cell biological processes, including epithelial sheet closure in development, wound healing, neuronal path finding, immune cell function, cell invasion, and metastasis of cancer cells.

Selected Publications
Tokuo H, Mabuchi K, Ikebe M. The motor activity of myosin-X promotes actin fiber convergence at the cell periphery to initiate filopodia formation. J Cell Biol. 2007;179(2):229-38.
PMID: 17954606

Saeki N, Tokuo H, Ikebe M. BIG1 is a binding partner of myosin IXb and regulates its Rho-GTPase activating protein activity. J Biol Chem. 2005;280(11):10128-34.
PMID: 15644318

Ozawa T, Araki N, Yunoue S, Tokuo H, Feng L, Patrakitkomjorn S, Hara T, Ichikawa Y, Matsumoto K, Fujii K, Saya H. The neurofibromatosis type 1 gene product neurofibromin enhances cell motility by regulating actin filament dynamics via the Rho-ROCK-LIMK2-cofilin pathway. J Biol Chem. 2005;280(47):39524-33.
PMID: 16169856

Tokuo H, Ikebe M. Myosin X transports Mena/VASP to the tip of filopodia. Biochem Biophys Res Commun. 2004;319(1):214-20.
PMID: 15158464

Yunoue S, Tokuo H, Fukunaga K, Feng L, Ozawa T, Nishi T, Kikuchi A, Hattori S, Kuratsu J, Saya H, Araki N. Neurofibromatosis type I tumor suppressor neurofibromin regulates neuronal differentiation via its GTPase-activating protein function toward Ras. J Biol Chem. 2003;278(29):26958-69.
PMID: 12730209

Tokuo H, Yunoue S, Feng L, Kimoto M, Tsuji H, Ono T, Saya H, Araki N. Phosphorylation of neurofibromin by cAMP-dependent protein kinase is regulated via a cellular association of N(G),N(G)-dimethylarginine dimethylaminohydrolase. FEBS Lett. 2001;494(1-2):48-53.
PMID: 11297733

PubMed:
Click here for a list of publications (searches the National Library of Medicine's PubMed database.)