In vitro co-expression chromatin assembly and remodeling platform for plant histone variants

Abstract

Abstract Histone variants play a central role in shaping the chromatin landscape in plants, yet, how their distinct combinations affect nucleosome properties and dynamics is still largely elusive. To address this, we developed a novel chromatin assembly platform for Arabidopsis thaliana, using wheat germ cell-free protein expression. Four canonical histones and five reported histone variants were used to assemble twelve A. thaliana nucleosome combinations. Seven combinations were successfully reconstituted and confirmed by supercoiling and micrococcal nuclease (MNase) assays. The effect of the remodeling function of the CHR11-DDR4 complex on these seven combinations was evaluated based on the nucleosome repeat length and nucleosome spacing index obtained from the MNase ladders. Overall, the current study provides a novel method to elucidate the formation and function of a diverse range of nucleosomes in plants.