Robert Yu-Lin Tsai

Robert Yu-Lin Tsai, Ph.D.

Associate Professor
Center for Cancer and Stem Cell Biology
Member of the GSBS Faculty

2121 W. Holcombe Blvd.
Houston, Texas 77030
Phone: 713-677-7690
Email: rtsai@ibt.tamhsc.edu
Lab Webpage: http://www.ibt.tamhsc.edu/labs/ccscb/

Education and Post-Graduate Training

Dr. Tsai received his undergraduate and MD degrees at National Taiwan University and an internship and residency in Neurology at the National Taiwan University Hospital. He received a Ph.D. in Neurosciences at Johns Hopkins University School of Medicine in 1996 and was a Research Fellow at the National Institute of Neurological Disorders and Stroke, National Institutes of Health (1997-2003). In 2003 he was appointed an Assistant Professor in the Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, The Texas A&M Health Science Center in the Texas Medical Center, Houston, Texas and promoted to tenured Associate Professor in 2008. He holds a joint appointment in the Department of Molecular and Cellular Medicine, College of Medicine, Texas A&M Health Science Center.

Teaching Interests

Graduate and Specialized Research Training in Stem Cell Biology

Research Interests

The research interest of my laboratory is focused on the molecular mechanism that drives the self-renewing proliferation of stem cells, with the hope that we can use this knowledge to enhance the endogenous regenerative process to repair damaged tissues caused by diseases or injuries, particularly in the central nervous system, and, on the flip side, to reduce the uncontrolled proliferation seen in metastatic and high-grade tumors. The biological systems we use are ES, primary neural stem cell culture, and cancer cell lines, as well as mouse genetic models. The molecular target of our present studies is a family of nucleolar GTPases, one of which, nucleostemin (NS), confers a unique nucleolar state in the stem cells. NS was previously identified as enriched in the stem cell population, and shown to play important roles in keeping the neural stem cells and cancer cells in the cell cycle. The activity of NS is regulated by a small molecule in the cells (GTP) that serves as a molecular switch controlling the on and off states. Our work suggests a model in which continuously dividing cells use NS as a sensor to control their rate of division in response to changes that take place in their microenvironment. The mechanism by which NS and NS-related genes control tissue homeostasis in adult animals is being addressed in the following directions: 1) defining the unique nucleolar state in stem cells; 2) determining the signaling pathway that regulates the expression and activity of nucleostemin (NS) in stem cells and during adult tissue regeneration; and 3) establishing the role of NS-expressing cells in the tumorigenic process, with an emphasis on the brain, breast, and prostate tumors.

Selected Publications

Five Most Significant Publications Prior to 2008

Tsai, R.Y.L. and McKay, R.D.G (2000) Cell Contact Regulates Fate Choice by Cortical Stem Cells. J. Neurosci. 20:3725-3735.

Tsai, R.Y.L. and McKay, R.D.G (2002) A Nucleolar Mechanism Controlling Cell Proliferation in Stem Cells and Cancer Cells. Genes Dev.: 16:2991-3003.

Tsai, R.YL. and McKay R.DG (2005) A Multistep, GTP-driven Mechanism Controlling the Dynamic Cycling of Nucleostemin. J. Cell Biol. 168:179-184.

Zhu, Q., Yasumoto, H., and Tsai, R. YL. (2006) Nucleostemin Delays Cellular Senescence and Negatively Regulates TRF1 Protein Stability. Mol Cell Biol. 24:9279-9290.

Meng, L, Zhu, Q, and Tsai, RYL. (2007) Nucleolar Trafficking of Nucleostemin Family Proteins: Common versus Protein-Specific Mechanisms. Mol Cell Biol. 27:8670-82. [EPub 2007 Oct. 8]

Publications 2008

Meng, L., Lin, T., and Tsai, R.YL. (2008) Nucleoplasmic Mobilization of Nucleostemin Stabilizes MDM2 and Promotes G2-M Progression and Cell Survival. J Cell Sci. 121:4037-4046 [EPub 2008 Nov. 25].

Publications 2009

Lin, Y., Chen, L., Lin, C., Luo, Y., Tsai, R.YL., and Wang, F. (2009) Neuron-derived FGF9 Is Essential for Scaffold Formation of Bergmann Radial Fibers and Migration of Granule Neurons in The Cerebellum. Dev Biol. 329: 44-54 [EPub 2009 Feb 20].

Pederson, T. and Tsai, R.YL. (2009) In Search of Non-Ribosomal Nucleolar Protein Function and Regulation. J Cell Biol. 184:771-776 [EPub 2009 Mar 16].

Zhu, Q., Meng, L., Hsu, J.K., Lin, T., Teishima, J., and Tsai, R.YL. (2009) GNL3L Stabilizes the TRF1 Complex and Promotes Mitotic Transition. J Cell Biol. 185:827-839.

Tsai, R.YL. and Meng, L. (2009) Nucleostemin: A Latecomer with New Tricks. Int J Biochem Cell Biol. 41: 2122-2124 [EPub 2009 Jun 6].

Tsai, R.YL. (2009) Nucleolar Modulation of TRF1: A Dynamic Way to Regulate Telomere and Cell Cycle by Nucleostemin and GNL3L. Cell Cycle. 8:2912-2916 [EPub 2009 Sep 16].

Texas A&M Health Science Center - Institute of Biomedical Sciences