Nucleosomes

Nucleosomes are the repeating unit of chromatin, and consist of approximately 147 base pairs of DNA wrapped around eight histone protein cores to allow chromosomal DNA to be packaged into a small volume. Nucleosomes are the 'beads' in the 'bead-on-a-string' depiction of chromatin.

Latest Research and Reviews

  • Research | | open

    Polycomb and Trithorax group proteins regulate silent and active gene expression states, but also allow poised states in pluripotent cells. Here the authors present a mathematical model that integrates data on Polycomb/ Trithorax biochemistry into a single coherent framework which predicts that poised chromatin is not bivalent as previously proposed, but is bistable, meaning that the system switches frequently between stable active and silent states.

    • Kim Sneppen
    •  & Leonie Ringrose
  • Research | | open

    Wataru Kobayashi et al. use cryo-EM to study the C-terminal ELYS subunit of the nuclear pore complex. They show that a three-residue stretch binds to the acidic patch of the nucleosome, providing new mechanistic insights into ELYS nucleosome interactions.

    • Wataru Kobayashi
    • , Yoshimasa Takizawa
    • , Maya Aihara
    • , Lumi Negishi
    • , Hajime Ishii
    •  & Hitoshi Kurumizaka
  • Reviews |

    Eukaryotes differ substantially from bacteria and archaea owing to their nucleosome-based packaging of DNA. In this Review, Talbert, Meers and Henikoff place gene regulation in an evolutionary context by discussing how the emergence and diversification of eukaryotic chromatin provided both challenges and opportunities for intricate mechanisms of gene regulation in eukaryotes.

    • Paul B. Talbert
    • , Michael P. Meers
    •  & Steven Henikoff
  • Research | | open

    Kinetochore function depends on H4K20 monomethylation in centromeric nucleosomes but the underlying mechanism is unclear. Here, the authors provide evidence that the centromere-specific nucleosome subunit CENP-A facilitates H4K20 methylation by enabling a conformational change of the H4 N-terminal tail.

    • Yasuhiro Arimura
    • , Hiroaki Tachiwana
    • , Hiroki Takagi
    • , Tetsuya Hori
    • , Hiroshi Kimura
    • , Tatsuo Fukagawa
    •  & Hitoshi Kurumizaka
  • Reviews |

    Chromatin accessibility comprises the positions, compaction and dynamics of nucleosomes, as well as the occupancy of DNA by other proteins such as transcription factors. In this Review, the authors discuss diverse methods for characterizing chromatin accessibility, how accessibility is determined and remodelled in cells and the regulatory roles of accessibility in gene expression and development.

    • Sandy L. Klemm
    • , Zohar Shipony
    •  & William J. Greenleaf
  • Research | | open

    Eukaryotic transcription requires passage of RNA polymerase II (Pol II) through chromatin, which is impaired by nucleosomes. Here the authors report the cryo-EM structure of transcribing Pol II engaged with a downstream nucleosome core particle at an overall resolution of 4.4 Å, providing insights into the mechanism of chromatin transcription.

    • Lucas Farnung
    • , Seychelle M. Vos
    •  & Patrick Cramer

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