title: A Quantitative Characterization of Nucleoplasmin/Histone Complexes Reveals Chaperone Versatility.
abstract: Nucleoplasmin (NP) is an abundant histone chaperone in vertebrate oocytes and embryos involved in storing and releasing maternal histones to establish and maintain the zygotic epigenome. NP has been considered a H2A-H2B histone chaperone, and recently it has been shown that it can also interact with H3-H4. However, its interaction with different types of histones has not been quantitatively studied so far. We show here that NP binds H2A-H2B, H3-H4 and linker histones with Kd values in the subnanomolar range, forming different complexes. Post-translational modifications of NP regulate exposure of the polyGlu tract at the disordered distal face of the protein and induce an increase in chaperone affinity for all histones. The relative affinity of NP for H2A-H2B and linker histones and the fact that they interact with the distal face of the chaperone could explain their competition for chaperone binding, a relevant process in NP-mediated sperm chromatin remodelling during fertilization. Our data show that NP binds H3-H4 tetramers in a nucleosomal conformation and dimers, transferring them to DNA to form disomes and tetrasomes. This finding might be relevant to elucidate the role of NP in chromatin disassembly and assembly during replication and transcription.
authors: Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), P.O. Box 644, E-48080 Bilbao, Spain.|Biofisika Institute (CSIC, UPV/EHU), P. O. Box 644, 48080 Bilbao, Spain.
authors: Noelia
authors: N
authors: Fernández-Rivero
authors: Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), P.O. Box 644, E-48080 Bilbao, Spain.|Biofisika Institute (CSIC, UPV/EHU), P. O. Box 644, 48080 Bilbao, Spain.
authors: Aitor
authors: A
authors: Franco
authors: Institute of Biocomputation and Physics of Complex Systems (BIFI), Joint Unit IQFR-CSIC-BIFI, Universidad de Zaragoza, C/Mariano Esquillor, Zaragoza 50018, Spain.|Department of Biochemistry and Molecular and Cell Biology, University of Zaragoza, Zaragoza 50009, Spain.|Instituto de Investigaciones Sanitarias de Aragón (IIS-A), Zaragoza 50009, Spain.|Fundación ARAID, Government of Aragón, Zaragoza 50018, Spain.
authors: Adrian
authors: A
authors: Velázquez-Campoy
authors: Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), P.O. Box 644, E-48080 Bilbao, Spain.|Biofisika Institute (CSIC, UPV/EHU), P. O. Box 644, 48080 Bilbao, Spain.
authors: Edurne
authors: E
authors: Alonso
authors: Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), P.O. Box 644, E-48080 Bilbao, Spain.|Biofisika Institute (CSIC, UPV/EHU), P. O. Box 644, 48080 Bilbao, Spain.
authors: Arturo
authors: A
authors: Muga
authors: Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), P.O. Box 644, E-48080 Bilbao, Spain.|Biofisika Institute (CSIC, UPV/EHU), P. O. Box 644, 48080 Bilbao, Spain.
authors: Adelina
authors: A
authors: Prado
mesh_terms: D000818:Animals; D004247:DNA / Q000378:metabolism; D005260:Female; D006657:Histones / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D018832:Molecular Chaperones / Q000235:genetics / Q000378:metabolism*; D056489:Nucleoplasmins / Q000235:genetics / Q000378:metabolism*; D009707:Nucleosomes / Q000378:metabolism; D009865:Oocytes; D010063:Ovum / Q000378:metabolism; D010766:Phosphorylation; D055503:Protein Multimerization; D011499:Protein Processing, Post-Translational; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D029867:Xenopus Proteins / Q000235:genetics / Q000378:metabolism*; D014982:Xenopus laevis
chemical_list: D006657:Histones; D018832:Molecular Chaperones; D056489:Nucleoplasmins; D009707:Nucleosomes; D011994:Recombinant Proteins; D029867:Xenopus Proteins; D004247:DNA