Back

Biography

Yawen Bai received his Ph.D. in Biophysics from the University of Pennsylvania Medical School. After postdoctoral work at the Scripps Research Institute, La Jolla, California, he became an investigator at the National Cancer Institute of the National Institutes of Health in Bethesda, Maryland since 1997. The research interests of his group include structural studies on protein folding intermediates, histone chaperones, epigenetic specification of centromeres and chromatin folding.

Abstract

Human genome is packaged into chromatin through association with small positively charged histone proteins. The structural unit of chromatin is the nucleosome, which consists of ~147 bp of DNA and two copies of each of the four core histones (H2A, H2B, H3 and H4). Numerous proteins regulate chromatin structure and function through specific binding to the nucleosome. The structural basis of many of these interactions is unknown. Structural determination of the nucleosome in complex with a protein by X-ray crystallography and single particle cryo-EM has proven to be very challenging in many cases due to difficulties to crystalize them and dissociation of the complex during cryo processes. On the other hand, the nucleosome is too large (> 200 KDa) for structural studies with conventional NMR methods. We have used methyl-TROSY [1] coupled with site-specific mutagenesis and paramagnetic spin labeling to investigate how the nucleosome is recognized by various chromatin factor proteins, including high-mobility group nucleosomal protein [2], centromere protein C [3] and linker histones [4,5]. Major results and future perspectives will be presented.

References:

  1. Tugarinov V, Hwang JE, Ollerenshaw JE, Kay LE. (2003) Cross-correlated relaxation enhanced 1H-13C NMR spectroscopy of methyl groups in very high molecular weight proteins and protein complexes. J Am Chem Soc 125, 10420-10428.
  2. Kato H, van Ingen H, Zhou BR, Feng H, Bustin M, Kay LE, Bai Y. (2011) Architecture of the high mobility groups nucleosomal protein 2-nucleosome complex as revealed by methyl-based NMR. Proc Natl Acad Sci 108, 12283-12288.
  3. Kato H, Jiang J, Zhou BR, Rozendaal M, Feng H, Ghirlando R, Xiao TS, Straight AF, Bai Y. (2013) A conserved mechanism for centromeric nucleosome recognition by centromere protein CENP-C. Science, 340, 1110-1113.
  4. Zhou BR, Feng H, Kato H, Dai L, Yang Y, Zhou Y, Bai Y. (2013) Structural insights into the histone H1-nucleosome complex. Proc Natl Acad Sci 110, 19390-19395.
  5. Zhou BR, Jiang J, Feng H, Ghirlando R, Xiao TS, Bai Y. (2015) Structural mechanisms of nucleosome recognition by linker histones. Mol Cell 58, 628-638.