Structural basis for H2A-H2B recognitions by human Spt16

The human facilitates chromatin transcription (FACT) complex, consisting of Spt16 and SSRP1, is a ver-satile histone chaperone that can engage free H2A-H2B dimer and H3-H4 tetramer (or dimer), and partially unraveled nucleosome. The C-terminal domain of human Spt16 (hSpt16-CTD) is the decisive element for engaging H2A-H2B dimer and partially unraveled nucleosome. The molecular basis of the H2A-H2B dimer recognitions by hSpt16-CTD is not fully comprehended. Here, we present a high-resolution snapshot of the recognitions of the H2A-H2B dimer by hSpt16-CTD via an acidic intrinsi-cally disordered (AID) segment, and reveal some distinct structural features of hSpt16-CTD as compared to the budding yeast Spt16-CTD.(c) 2023 Elsevier Inc. All rights reserved.

Automated summary

The human facilitates chromatin transcription (FACT) complex, composed of Spt16 and SSRP1, can bind to free H2A-H2B dimer and H3-H4 tetramer (or dimer), as well as partially unraveled nucleosome. The C-terminal domain of human Spt16 (hSpt16-CTD) is crucial for the recognition of H2A-H2B dimer and partially unraveled nucleosome. This study reveals the molecular basis of H2A-H2B dimer recognition by hSpt16-CTD through an acidic intrinsically disordered (AID) segment and identifies some unique structural features of hSpt16-CTD compared to yeast Spt16-CTD. (c) 2023 Elsevier Inc. All rights reserved.