Distinct histone H3-H4 binding modes of sNASP reveal the basis for cooperation and competition of histone chaperones.
Liu, C.P., Jin, W., Hu, J., Wang, M., Chen, J., Li, G., Xu, R.M.(2021) Genes Dev 35: 1610-1624
- PubMed: 34819355 
- DOI: https://doi.org/10.1101/gad.349100.121
- Primary Citation of Related Structures:  
7V6P, 7V6Q - PubMed Abstract: 
Chromosomal duplication requires de novo assembly of nucleosomes from newly synthesized histones, and the process involves a dynamic network of interactions between histones and histone chaperones. sNASP and ASF1 are two major histone H3-H4 chaperones found in distinct and common complexes, yet how sNASP binds H3-H4 in the presence and absence of ASF1 remains unclear. Here we show that, in the presence of ASF1, sNASP principally recognizes a partially unfolded Nα region of histone H3, and in the absence of ASF1, an additional sNASP binding site becomes available in the core domain of the H3-H4 complex. Our study also implicates a critical role of the C-terminal tail of H4 in the transfer of H3-H4 between sNASP and ASF1 and the coiled-coil domain of sNASP in nucleosome assembly. These findings provide mechanistic insights into coordinated histone binding and transfer by histone chaperones.
Organizational Affiliation: 
National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.