NAP1-Related Protein 1 (NRP1) has multiple interaction modes for chaperoning histones H2A-H2B
Qiang Luo, Baihui Wang, Zhen Wu, Wen Jiang, Yueyue Wang, Kangxi Du, Nana Zhou, Lina Zheng, Jianhua Gan, Wen‐Hui Shen, Jinbiao Ma, Aiwu Dong
Abstract
NAP1-Related Protein 1 (NRP1) complexed with H2A-H2B and uncovered a previously unknown interaction mechanism in histone chaperoning. Both in vitro binding and in vivo plant rescue assays proved that interaction mediated by the N-terminal α-helix (αN) domain is essential for NRP1 function. In addition, the C-terminal acidic domain (CTAD) of NRP1 binds to H2A-H2B through a conserved mode similar to other histone chaperones. We further extended previous knowledge of the NAP1-conserved earmuff domain by mapping the amino acids of NRP1 involved in association with H2A-H2B. Finally, we showed that H2A-H2B interactions mediated by αN, earmuff, and CTAD domains are all required for the effective chaperone activity of NRP1. Collectively, our results reveal multiple interaction modes of a NAP1 family histone chaperone and shed light on how histone chaperones shield H2A-H2B from nonspecific interaction with DNA.