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H2A.Z is an essential histone variant implicated in the regulation of key nuclear events. However, the metazoan chaperones responsible for H2A.Z deposition and its removal from chromatin remain unknown. Here we report the identification and characterization of the human protein ANP32E as a specific H2A.Z chaperone. We show that ANP32E is a member of the presumed H2A.Z histone-exchange complex p400/TIP60. ANP32E interacts with a short region of the docking domain of H2A.Z through a new motif termed H2A.Z interacting domain (ZID). The 1.48 Å resolution crystal structure of the complex formed between the ANP32E-ZID and the H2A.Z/H2B dimer and biochemical data support an underlying molecular mechanism for H2A.Z/H2B eviction from the nucleosome and its stabilization by ANP32E through a specific extension of the H2A.Z carboxy-terminal [alpha]-helix. Finally, analysis of H2A.Z localization in ANP32E.sup.-/- cells by chromatin immunoprecipitation followed by sequencing shows genome-wide enrichment, redistribution and accumulation of H2A.Z at specific chromatin control regions, in particular at enhancers and insulators. Human protein ANP32E is a histone chaperone that promotes removal of H2A.Z from chromatin. Chaperoning a histone variant The histone H2A.Z is a variant of histone H2A, one of the canonical histones present in the chromatin of eukaryotic cells. H2A.Z has important functions in transcription and other nuclear processes. Here, Ali Hamiche and colleagues identify the human protein ANP32E as an H2A.Z chaperone capable of promoting the removal of H2A.Z from chromatin. Biochemical and structural data indicate the molecular basis for H2A.Z recognition and eviction by ANP32E, and genome-wide mapping analyses reveal how ANP32E regulates H2A.Z occupancy at important regulatory regions of the genome., Author(s): Arnaud Obri [sup.1] , Khalid Ouararhni [sup.1] , Christophe Papin [sup.1] , Marie-Laure Diebold [sup.2] , Kiran Padmanabhan [sup.3] , Martin Marek [sup.2] , Isabelle Stoll [sup.1] , Ludovic [...]

H2A.Z is an essential histone variant implicated in the regulation of key nuclear events. However, the metazoan chaperones responsible for H2A.Z deposition and its removal from chromatin remain unknown. Here we report the identification and characterization of the human protein ANP32E as a specific H2A.Z chaperone. We show that ANP32E is a member of the presumed H2A.Z histone-exchange complex p400/TIP60. ANP32E interacts with a short region of the docking domain of H2A.Z through a new motif termed H2A.Z interacting domain (ZID). The 1.48 Å resolution crystal structure of the complex formed between the ANP32E-ZID and the H2A.Z/H2B dimer and biochemical data support an underlying molecular mechanism for H2A.Z/H2B eviction from the nucleosome and its stabilization by ANP32E through a specific extension of the H2A.Z carboxy-terminal α-helix. Finally, analysis of H2A.Z localization in [ANP32E.sup.-/-] cells by chromatin immunoprecipitation followed by sequencing shows genome-wide enrichment, redistribution and accumulation of H2A.Z at specific chromatin control regions, in particular at enhancers and insulators., H2A.Z is a histone variant that is highly conserved across all eukaryotes (1), and is required for survival in fly and mouse (2,3). H2A.Z belongs to the H2A family but [...]

The human histone H3 variant, CENP-A, replaces the conventional histone H3 in centromeric chromatin and, together with centromerespecific DNA-binding factors, directs the assembly of the kinetochore. We purified the prenucelosomal e-CENP-A complex. We found that HJURP, a member of the complex, was required for cell cycle specific targeting of CENP-A to centromeres. HJURP facilitated efficient deposition of CENP-A/H4 tetramers to naked DNA in vitro. Bacterially expressed HJURP binds at a stoichiometric ratio to the CENP-A/H4 tetramer but not to the H3/H4 tetramer. The binding occurred through a conserved HJURP short N-terminal domain, termed CBD. The novel characteristic identified in vertebrates that we named TLTY box of CBD, was essential for formation of the HJURP-CENP-A/H4 complex. Our data identified HJURP as a vertebrate CENP-A chaperone and dissected its mode of interactions with CENP-A. histone chaperone | histone variant doi/ 10.1073/pnas.0913709107