19th-banner-rev.gif

Book of Abstracts: Albany 2009

category image Albany 2009
Conversation 16
June 16-20 2009
© Adenine Press (2008)

Chromatin higher order structure and regulation of its compaction

During the past decade it has become evident that histone and DNA modifications are key regulators of all nuclear processes whose substrate is DNA. Whilst the effects of, for instance, histone post-translational modification on transcription are well-documented, there is no mechanistic understanding of how such modification regulate chromatin condensation directly, or indirectly. Such an understanding is dependent on knowledge of the three-dimensional structure of chromatin. Although the structure of the first level of DNA folding, the nucleosome core, is known at atomic resolution, the structure of the second level of folding, whereby a string of nucleosomes folds into a fibre with an approximate diameter of 30 nm - the ?30-nm? chromatin fibre, remains undetermined. I will describe our studies on the higher orders structure of chromatin with two primary aims:
  1. Determination of the structure of the ?30nm? chromatin fibre to provide an understanding of fibre topology and nucleosome-nucleosome interactions.
  2. Biophysical characterization of the effects of the linker histone and histone modifications on the compaction and stability of chromatin higher order structure.
References and Footnotes
  1. Robinson, J. J. P., Fairall, L., Huynh, V. A. T. and Rhodes, D., EM measurements define the dimensions of the ?30nm? chromatin fiber: Evidence for a compact, interdigitated structure, Proc. Natl. Acad. Sci. USA 103, 6506-6511 (2006)
  2. Robinson, P.J., An, W., Routh, A., Martino, F., Chapman, L., Roeder, R.G. and Rhodes D., 30 nm chromatin fibre decompaction requires both H4-K16 acetylation and linker histone eviction, J. Mol. Biol. 12;381(4):816-825 (2008)
  3. Routh, A., Sandin, S. and Rhodes, D., Nucleosome repeat length and linker histone stoichiometry determine chromatin fiber structure, Proc. Natl. Acad. Sci. U S A. 105(26):8872-7 (2008)

    Daniela Rhodes
    Sara Sandin
    Andrew Routh
    Philip Robinson

    MRC Laboratory of Molecular Biology
    Hills Road
    Cambridge, CB2 0QH, UK

    Tel: +44 (0)1223 402441
    Fax: +44 (0)1223 213556
    email Daniela Rhodes