@article{SHIOI2025103891,

title = {Mechanistic insights into RAD51-mediated nucleosome binding and remodeling in homologous recombination},

author = {Takuro Shioi and Suguru Hatazawa and Yoshimasa Takizawa and Hitoshi Kurumizaka},

url = {https://www.sciencedirect.com/science/article/pii/S1568786425000874},

doi = {https://doi.org/10.1016/j.dnarep.2025.103891},

issn = {1568-7864},

year  = {2025},

date = {2025-09-13},

urldate = {2025-01-01},

journal = {DNA Repair},

pages = {103891},

abstract = {Eukaryotic cells organize their genomic DNA into chromatin to achieve both compact packaging and precise regulation of essential processes, including DNA repair. Depending on the type of damage, distinct repair pathways are activated through the targeted recruitment of repair factors to chromatin. RAD51 is the central recombinase in homologous recombination (HR) and forms nucleoprotein filaments, but its mode of chromatin engagement has remained elusive. In this review, we summarize recent progress in the structural and biochemical understanding of DNA repair within chromatin, with a particular focus on RAD51 and its role in HR. Specifically, we review newly determined cryo-electron microscopy (cryo-EM) structures of RAD51 bound to nucleosomes, revealing how RAD51 assembles on chromatin, recognizes DNA damage sites, and remodels nucleosomes into filamentous intermediates. We summarize current insights into how HR-associated proteins regulate RAD51 activity on chromatin, ensuring the fidelity of each step in HR. We conclude by outlining future directions for elucidating the downstream mechanisms of RAD51-mediated HR in the chromatin context.},

keywords = {Chromatin, Chromatin remodeler, Cryo-electron microscopy, Homologous recombination, Kurumizaka G, Nucleosome, RAD51},

pubstate = {published},

tppubtype = {article}

}

@article{https://doi.org/10.1038/s44318-025-00473-6,

title = {Structural basis of RNAPII transcription on the nucleosome containing histone variant H2A.B},

author = {Munetaka Akatsu and Rina Hirano and Tomoya Kujirai and Mitsuo Ogasawara and Haruhiko Ehara and Shun-ichi Sekine and Yoshimasa Takizawa and Hitoshi Kurumizaka},

url = {https://www.embopress.org/doi/abs/10.1038/s44318-025-00473-6},

doi = {https://doi.org/10.1038/s44318-025-00473-6},

year  = {2025},

date = {2025-05-30},

journal = {The EMBO Journal},

abstract = {AbstractH2A.B is a distant histone H2A variant associated with actively transcribed regions of the genome, suggesting its positive role in promoting transcription. In the present study, we demonstrate that the RNA polymerase II elongation complex (EC) transcribes the nucleosome containing H2A.B more efficiently than that with canonical H2A in vitro. Our cryo-electron microscopy analysis of the H2A.B nucleosome during transcription revealed that the proximal H2A.B-H2B dimer is released from the nucleosome as the EC transcribes the proximal half of the nucleosomal DNA. This dissociation, which is not observed in the canonical H2A nucleosome, likely enhances the EC elongation efficiency in the H2A.B nucleosome. Mutational analyses suggested that the unique short C-terminal region of H2A.B alone enhances EC elongation efficiency when substituted for its counterpart in canonical H2A. Additionally, other regions of H2A.B contribute to this enhancement. These structural and biochemical findings provide new insights into the role of H2A.B in regulating gene expression.},

keywords = {Chromatin, H2A.B, Histone Variant, Kurumizaka G, Nucleosome, Transcription},

pubstate = {published},

tppubtype = {article}

}