title: The H3 chaperone function of NASP is conserved in Arabidopsis.
abstract: Histones are abundant cellular proteins but, if not incorporated into chromatin, they are usually bound by histone chaperones. Here, we identify Arabidopsis NASP as a chaperone for histones H3.1 and H3.3. NASP interacts in vitro with monomeric H3.1 and H3.3 as well as with histone H3.1-H4 and H3.3-H4 dimers. However, NASP does not bind to monomeric H4. NASP shifts the equilibrium between histone dimers and tetramers towards tetramers but does not interact with tetramers in vitro. Arabidopsis NASP promotes [H3-H4]2tetrasome formation, possibly by providing preassembled histone tetramers. However, NASP does not promote disassembly of in vitro preassembled tetrasomes. In contrast to its mammalian homolog, Arabidopsis NASP is a predominantly nuclear protein. In vivo, NASP binds mainly monomeric H3.1 and H3.3. Pulldown experiments indicated that NASP may also interact with the histone chaperone MSI1 and a HSC70 heat shock protein.
authors.affiliation: Department of Plant Biology and Linnean Center for Plant Biology, Swedish University of Agricultural Sciences, PO-Box 7080, SE-75007, Uppsala, Sweden.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Maksimov
authors.affiliation: Department of Plant Biology and Linnean Center for Plant Biology, Swedish University of Agricultural Sciences, PO-Box 7080, SE-75007, Uppsala, Sweden.
authors.forename: Miyuki
authors.initials: M
authors.lastname: Nakamura
authors.affiliation: Department of Biology and Zurich-Basel Plant Science Center, ETH Zurich, CH-8092, Zurich, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Wildhaber
authors.affiliation: Functional Genomics Center Zurich, University of Zurich/ETH Zurich, CH-8057, Zurich, Switzerland.
authors.forename: Paolo
authors.initials: P
authors.lastname: Nanni
authors.affiliation: Department of Chemistry-BMC, Analytical Chemistry and Science for Life Laboratory, Uppsala University, SE-75124, Uppsala, Sweden.
authors.forename: Margareta
authors.initials: M
authors.lastname: Ramström
authors.affiliation: Department of Chemistry-BMC, Analytical Chemistry and Science for Life Laboratory, Uppsala University, SE-75124, Uppsala, Sweden.
authors.forename: Jonas
authors.initials: J
authors.lastname: Bergquist
authors.affiliation: Department of Plant Biology and Linnean Center for Plant Biology, Swedish University of Agricultural Sciences, PO-Box 7080, SE-75007, Uppsala, Sweden.
authors.forename: Lars
authors.initials: L
authors.lastname: Hennig
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002843:Chromatin / Q000378:metabolism; D018832:Molecular Chaperones / Q000235:genetics / Q000378:metabolism*; D009707:Nucleosomes / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D002843:Chromatin; D018832:Molecular Chaperones; D009707:Nucleosomes
keywords: 
  Arabidopsis thaliana
  ; chaperone; chromatin; histone; nucleosome