We are interested in the role and mechanism of cell signaling focusing especially on the transduction of the Ca2+ signaling. We are studying mainly four core projects as follows.
1. Calcium Signaling in Brain
Calcium signaling in the brain is essential to maintain a normal brain structure and function. We shall study molecular mechanisms by which the IP3 receptor control neuronal morphology and function. Glial cells surround neurons to modulate their functions, so glial IP3 receptors will be also targets for our study.
2. Calcium Signaling in Differentiation
We discovered IP3 receptor is involved in cell differentiation and development. We shall study how IP3R is involved in cell fate determination by detailed analysis of local Ca2+ signaling mediated by IP3 receptors at cellular microdomains.
3. IP3 receptor Structure and Function
Recent studies have demonstrated atomic structures of IP3 receptors and ryanodine receptors, suggesting a shared gating mechanism. However, we have never known how IP3 and Ca2+ bind to open the channel. We shall study the gating mechanism controlled by IP3 and Ca2+.
4. IRBIT Function and Mechanism
IRBIT is an IP3 receptor binding protein released in the presence of IP3, which is discovered and named in the Mikoshiba lab. IRBIT regulates Ca2+ signaling, the intracellular pH homeostasis, and ribonucleotide reductase which controls tumor growth. We shall study molecular mechanism of how IRBIT controls these cellular signaling.