To slide or not to slide: key role of the hexasome in chromatin remodeling revealed

Hexasomes are non-canonical nucleosomes that package DNA with six instead of eight histones. First discovered 40 years ago as a consequence of transcription, two near-atomic-resolution cryo-EM structures of the hexasome in complex with the chromatin remodeler INO80 have now started to unravel its mechanistic impact on the regulatory landscape of chromatin. Loss of one histone H2A–H2B dimer converts inactive nucleosomes into distinct and favorable substrates for ATP-dependent chromatin remodeling. Hexasomes are non-canonical nucleosomes that package DNA with six instead of eight histones. Here, the author contextualizes two recent studies on the interplay of the chromatin remodeler INO80 with hexasomes with historical literature on the subject.