Breaking and Tessellating the Contiguous Nuclear Genome

  • Kojiro Ishii


“Preformation” and “epigenesis” were the two antithetical concepts theoretical biologists of the early 18th century advocated to explain ontogenesis. Apparently their repercussions still remain and keep vibrating, at least in a subject of the current biological study; i.e. how the usage of “genetic” information, an ultimate “preformed” material, is controlled by the “epigenetics,” a derivative of “epigenesis,” and conversely, how such “epigenetic” regulations are restricted by the cisacting “genetic” elements. The genetic elements described in the latter issue are experimentally defined as “boundary elements” or “insulators,” and have been studied extensively for decades (Gerasimova and Corces 2001). Here I am going to summarize some of the recent advances to unravel the mechanics of boundary elements that hinder spread of epigenetic heterochromatin. They appear to be classified functionally into two groups, the antagonistic chromosomal effect and the structural tethering in the nucleus.


Boundary Element Nuclear Pore Complex Chromatin Domain Histone Variant Chromatin Fiber 
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© Springer 2007

Authors and Affiliations

  • Kojiro Ishii
    • 1
  1. 1.PRESTO, Japan Science and Technology Agency, Division of Cell Biology, Institute of Life ScienceKurume UniversityKurumeJapan

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