Biomedical Science

The mammalian brain serves as a center for cognitive function, and the neurons relay and store information about our surroundings and experiences. Proper development of neuronal circuit is thus critical to the mental health of an individual, and requires a series of steps such as neuronal cell differentiation, migration, outgrowth of neurites, and synapse formation. The molecular mechanisms underlying these phenomena are incompletely understood, making treatment of brain and mental diseases difficult. Our goal is to clarify the functions of genes, proteins, and lipids in the brain development and function and contribute to the understanding of brain and mental diseases and to development of new drugs. Currently we are particularly interested in a gene called Reelin, which is important both in development and in higher function of the brain. We also work on genes that have relation with dyslexia (reading disability) and proteins that may regulate membrane dynamics of the neurons.

(1) Reelin is a secreted protein that is essential for brain development. We found that the C-terminal region of Reelin is critically involved in the association with the target neurons.

(2) We are interested in the effect of disease-related genes in the regulation of neuronal morphology and dynamics. We found that one of the dyslexia-related genes quite robustly induces branching and thorny structures in dendrites of hippocampal neurons.

(3) We take advantage of mutant mice and gene-manipulated mice. By staining with marker antibodies, we are able to locate specific types of neurons in the mouse brain. Combination of these techniques has revealed the specific function of the gene in the brain development.