8eu2
Class3 of the INO80-Hexasome complexClass3 of the INO80-Hexasome complex
Structural highlights
FunctionH3C_XENLA Core component of nucleosome. Nucleosomes wrap and compact DNA into chromatin, limiting DNA accessibility to the cellular machineries which require DNA as a template. Histones thereby play a central role in transcription regulation, DNA repair, DNA replication and chromosomal stability. DNA accessibility is regulated via a complex set of post-translational modifications of histones, also called histone code, and nucleosome remodeling. Publication Abstract from PubMedUnlike other chromatin remodelers, INO80 preferentially mobilizes hexasomes, which can form during transcription. Why INO80 prefers hexasomes over nucleosomes remains unclear. Here, we report structures of S. cerevisiae INO80 bound to a hexasome or a nucleosome. INO80 binds the two substrates in substantially different orientations. On a hexasome, INO80 places its ATPase subunit, Ino80, at superhelical location (SHL)-2, across from SHL-6/-7 as previously seen on nucleosomes. Our results suggest that INO80 action on hexasomes resembles action by other remodelers on nucleosomes, such that Ino80 is maximally active near SHL-2. The SHL-2 position also plays a critical role for nucleosome remodeling by INO80. Overall, the mechanistic adaptations used by INO80 for preferential hexasome sliding imply that sub-nucleosomal particles play considerable regulatory roles. Reorientation of INO80 on hexasomes reveals basis for mechanistic versatility.,Wu H, Munoz EN, Hsieh LJ, Chio US, Gourdet MA, Narlikar GJ, Cheng Y Science. 2023 Jun 28. doi: 10.1126/science.adf4197. PMID:37384669[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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