|Prof I-hsin Su is currently in the School of Biological Sciences since 2007. She received her Bachelor degree in Agronomy from National Taiwan University, Master and Ph.D. degrees from the University of Cologne, German, respectively. After her graduation, she continued her post-doctoral study at the Rockefeller University, New York, USA, where she was promoted to Research Assistant Professor in 2006. Her research interests include molecular immunology, and signal transduction. She has done significant research work in her research areas, attended or invited to attend over 10 top quality international conferences and published more than 10 top quality journal papers, including nature immunology and cell. Dr. I-hsin Su is a member of New York Academy of Sciences and Society of Immunology in Singapore.|
|Our research centers on the molecular mechanisms by which the development and function of immune cells are regulated. We have identified that a polycomb group protein Ezh2 is required for differentiation of early lymphoid precursors and immune responses of mature lymphocytes. Using a conditional Ezh2-deficient mouse, we have demonstrated that Ezh2-dependent histone H3 lysine 27 (H3-K27) methylation regulates immunoglobulin heavy chain (Igh) gene rearrangement and early B cell development. Our work has established, for the first time, the important role of histone methylation in antigen receptor rearrangement and lymphocyte development.
The histone-modifying function of Ezh2 is consistent with its predominant nuclear localization in various cell types. While the role of Ezh2 in B cells and T cell precursors is more dominant in the nucleus, we found that Ezh2 is crucial for TCR-mediated cytosolic signaling in mature T cells. Our recent study has shown that the Ezh2 complex is also present in the cytosol, and there it acquires an unexpected role in cell signaling: the cytosolic Ezh2 methyltransferase complex controls receptor-induced Rho-family GTPase activity and actin polymerization in a methylation-dependent manner in T cells and fibroblasts.
The molecular mechanisms by which Ezh2 regulate GTPase activity and actin polymerization are still elusive. However, given the methyltransferase nature of Ezh2, it is feasible that Ezh2 regulates cell signaling through protein methylation. We will further explore the dual functions of lysine methylation in 1) cytosolic cell signaling and basic cellular processes, and 2) epigenetic regulation of lymphocyte development and immune responses.
- Functional Signifiance of the Ezh2-Vav1 Interaction in normal & tumor cells
- The Role of Cytosolic Ezh2 in prostate cancer
- The role of Polycomb Group Protein Ezh2 in immune Response of Dendritic cells
- Transcriptional Regulation of Ezh2 Expression in Immune Cells and Lymphoma
- Wang, L., Jin, Q., Lee, J.E., Su, I-H., and Ge, K. (2010). Histone H3K27 methyltransferase Ezh2 represses Wnt genes to facilitate adipogenesis.. PNAS, 107(16), 7317-22.
- Xu, S., Huo, J., Gunawan, M., Su, I-H., and Lam, K.P. (2009). Activated dectin-1 localizes to lipid raft microdomains for signaling and activation of phagocytosis and cytokine production in dendritic cells.. Journal of Biological Chemistry, 284(33), 22005-22011.
- Chen N., Gu, X., Su, I-H., Bottino, R., Contreras, J.L. Tarakhovsky A., Kim S-K. (2009). Polycomb protein Ezh2 regulates pancreatic beta-cell Ink4a/Arf expression and regeneration in diabetes mellitus.. Genes & Development, .
- Ezhkova E., H. Pasolli A., Parker J., Stokes N., Su I-H., Hannon G., Tarakhovsky A., Fuchs E.Cell 2009, 136, 1122-1135. (2009). Ezh2 orchestrates gene expression for the stepwise differentiation of tissue-specific stem cells.. Cell, 136, 1122-1135.
- Su I-H. and Tarakhovsky A. (2006). Lysine methylation and ?signaling memory?. Current Opinion in Immunology, 18(2), 152-7.