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Histone chaperone-mediated co-expression assembly of tetrasomes and nucleosomes.

ABSTRACT: The nucleosome, a basic unit of chromatin found in all eukaryotes, is thought to be assembled through the orchestrated activity of several histone chaperones and chromatin assembly factors in a stepwise manner, proceeding from tetrasome assembly, to H2A/H2B deposition, and finally to formation of the mature nucleosome. In this study, we demonstrate chaperone-mediated assembly of both tetrasomes and nucleosomes on the well-defined Widom 601 positioning sequence using a co-expression/reconstitution wheat germ cell-free system. The purified tetrasomes and nucleosomes were positioned around the center of a given sequence. The heights and diameters were measured by atomic force microscopy. Together with the reported unmodified native histones produced by the wheat germ cell-free platform, our method is expected to be useful for downstream applications in the field of chromatin research.

SUBMITTER: Okimune KI

PROVIDER: S-EPMC8564334 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Histone chaperone-mediated co-expression assembly of tetrasomes and nucleosomes.

Okimune Kei-Ichi KI Hataya Shogo S Matsumoto Kazuki K Ushirogata Kanako K Banko Petra P Takeda Seiji S Takasuka Taichi E TE

FEBS open bio 20211019 11

The nucleosome, a basic unit of chromatin found in all eukaryotes, is thought to be assembled through the orchestrated activity of several histone chaperones and chromatin assembly factors in a stepwise manner, proceeding from tetrasome assembly, to H2A/H2B deposition, and finally to formation of the mature nucleosome. In this study, we demonstrate chaperone-mediated assembly of both tetrasomes and nucleosomes on the well-defined Widom 601 positioning sequence using a co-expression/reconstitutio ...[more]

PMID: 34614293

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