New Faculty

Xiaoying Bai, Ph.D. (Spring 2012)
Xin Liu, Ph.D. (Fall 2011)
Yunsun Nam, Ph.D. (Spring 2013)

Xiaoying Bai, Ph.D.


CPRIT Junior Faculty Recruitment Awardee

Topic: “Transcriptional Pausing: A Unique Mechanism in the Regulation of Hematopoietic Differentiation”

Training
M.D., Clinical Medicine, 1991-1996, Peking University Health Science Center, Beijing
Ph.D., Developmental Biology, 1999-2004, Baylor College of Medicine (Dr. Mitzi Kuroda)
Postdoc, 2005-present, Children’s Hospital Boston/Harvard Med (Dr. Leonard Zon)

Research
Dr. Bai is using zebrafish as a genetic and developmental model in combination with mammalian systems to study transcriptional mechanisms that regulate the differentiation of hematopoietic stem cells, focusing on the interplay between different transcriptional phases. She will also study the epigenetic regulation affecting the Pol II elongation through chromatin and identify novel pathways interacting with the elongation machinery. These studies will provide a better understanding of how the RNA Pol II machinery affects cell fate determination during normal and malignant hematopoiesis.

Key Publications
Bai X, Kim J, Yang Z, Jurynec M, Akie T, Lee J, LeBlanc J, Sessa A, Jiang H, DiBiase A, Zhou Y, Grunwald D, Lin S, Cantor A, Orkin S, and Zon LI. (2010) TIF1γ controls erythroid cell fate by regulating transcriptional elongation. Cell. 142: 133-43

Bai X, Larschan E, Kwon SY, Badenhorst P, and Kuroda MI. (2007) Regional control of chromatin organization by noncoding roX RNAs and the NURF remodeling complex in Drosophila melanogaster. Genetics 176:1491-9

Xin Liu, Ph.D.


CPRIT Junior Faculty Recruitment Awardee
UT Southwestern Endowed Scholars Awardee


Topic: “Molecular Basis of Transcription Preinitiation and Initiation by RNA Polymerase II”

Training
BS, Biochemistry, 1996-2000, Nanjing University, China
Ph.D., Chemistry, 2001-2007, University of Pennsylvania (Dr. Ronen Marmorstein)
Postdoc, 2008-Present, Stanford University School of Medicine (Dr. Roger Kornberg)

Research
Dr. Liu has used structural biology to study the molecular mechanisms of pRb inactivation by a viral oncoprotein, the structural basis of protein acetylation by p300/CBP, and the mechanisms of transcriptional initiation by RNA polymerase II and associated factors. In his own lab, he will address the molecular mechanisms of start site selection for RNA polymerase II. In parallel, he will explore the RNA polymerase II transcription in the context of the three-dimensional structure of the genome, focusing on transcription-dependent gene looping.

Key Publications
Liu X, Bushnell DA, Silva DA, Huang X, Kornberg RD. (2011) Initiation complex structure and promoter proofreading. Science. 2011 Jul 29;333(6042):633-7.

Liu X, Bushnell DA, Wang D, Calero G, Kornberg RD. (2010) Structure of an RNA polymerase II-TFIIB complex and the transcription initiation mechanism. Science. Jan 8;327(5962):206-9. 3.

Liu X, Wang L, Zhao K, Thompson PR, Hwang Y, Marmorstein R, Cole PA. (2008) The structural basis of protein acetylation by the p300/CBP transcriptional coactivator. Nature. Feb 14;451(7180):846-50.

Liu X, Marmorstein R. (2007) Structure of the retinoblastoma protein bound to adenovirus E1A reveals the molecular basis for viral oncoprotein inactivation of a tumor suppressor. Genes Dev. Nov 1;21(21):2711-6.

Yunsun Nam, Ph.D.

Yunsun Nam, Ph.D.

CPRIT Junior Faculty Recruitment Awardee

UT Southwestern Endowed Scholars Awardee

Topic: “Mechanisms underlying gene regulation by non-coding RNAs”
Lab Website 

Training
A.B, Biochemical Sciences, 1995-1999, Harvard College, Cambridge, MA.
Ph.D., Biological Chemistry and Molecular Pharmacology, 1999-2006, Harvard University (Dr. Stephen C. Blacklow), Boston, MA
Postdoc, 2006-2008, Department of Cell Biology, Harvard Medical School (Dr. Tom A. Rapoport), Boston, MA
Postdoc, 2009-2012, Department of Biological Chemistry and Molecular Pharmacology (Dr. Piotr Sliz), Boston, MA

Research
Dr. Nam studies mechanisms of non-coding RNAs and their role in gene regulation important for development and cancer. A major focus of her research is the molecular mechanism and regulation of microRNA processing. She uses various biochemical and biophysical approaches including X-ray crystallography, NMR spectroscopy, molecular biology, nucleic acid/protein biochemistry, high throughput sequencing, and eukaryotic cell-based studies. The long term goal is not only to elucidate how ncRNAs work but also to identify new avenues for developing therapeutics.

Key Publications

Nam, Y., Chen, C., Gregory, R.I., Chou, J.J., and Sliz, P (2011). Molecular basis for interaction of let-7 microRNAs with Lin28. Cell 147: 1080–1091. 

Lazarus, M. B.*, Y. Nam*, J. Jiang, P. Sliz and S. Walker (2011). Structure of human O-GlcNAc transferase and its complex with a peptide substrate. Nature 469(7331): 564-567. 

Erlandson, K. J., S. B. M. Miller, Y. Nam, A. R. Osborne, J. Zimmer and T. A. Rapoport (2008). A role for the two-helix finger of the SecA ATPase in protein translocation. Nature 455(7215): 984-987. 

Zimmer, J., Y. Nam and T. A. Rapoport (2008). Structure of a complex of the ATPase SecA and the protein-translocation channel. Nature 455(7215): 936-943. 

Nam, Y., P. Sliz, W. S. Pear, J. C. Aster and S. C. Blacklow (2007). Cooperative assembly of higher-order Notch complexes functions as a switch to induce transcription. Proc Nat Acad Sci 104(7): 2103-2108. 

Nam, Y.*, P. Sliz*, L. Song, J. C. Aster and S. C. Blacklow (2006). Structural basis for cooperativity in recruitment of MAML coactivators to Notch transcription complexes. Cell 124(5): 973-983.