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Crystal structure and function of human nucleoplasmin (npm2): a histone chaperone in oocytes and embryos.
Platonova O, Akey IV, Head JF, Akey CW.
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Human Npm2 is an ortholog of Xenopus nucleoplasmin (Np), a chaperone that binds histones. We have determined the crystal structure of a truncated Npm2-core at 1.9 Å resolution and show that the N-terminal domains of Npm2 and Np form similar pentamers. This allowed us to model an Npm2 decamer which may be formed by hydrogen bonds between quasi-conserved residues in the interface between two pentamers. Interestingly, the Npm2 pentamer lacks a prototypical A1-acidic tract in each of its subunits. This feature may be responsible for the inability of Npm2-core to bind histones. However, Npm2 with a large acidic tract in its C-terminal tail (Npm2-A2) is able to bind histones and form large complexes. Fluorescence resonance energy transfer experiments and biochemical analysis of loop mutations support the premise that nucleoplasmins form decamers when they bind H2A-H2B dimers and H3-H4 tetramers simultaneously. In the absence of histone tetramers, these chaperones bind H2A-H2B dimers with a single pentamer forming the central hub. When taken together, our data provide insights into the mechanism of histone binding by nucleoplasmins.
Adams,
PHENIX: building new software for automated crystallographic structure determination.
2002, Pubmed
Adams,
PHENIX: building new software for automated crystallographic structure determination.
2002,
Pubmed Akey,
Histone chaperones and nucleosome assembly.
2003,
Pubmed Bañuelos,
Phosphorylation of both nucleoplasmin domains is required for activation of its chromatin decondensation activity.
2007,
Pubmed
,
Xenbase Bañuelos,
Activation mechanism of the nuclear chaperone nucleoplasmin: role of the core domain.
2003,
Pubmed
,
Xenbase Brünger,
Crystallography & NMR system: A new software suite for macromolecular structure determination.
1998,
Pubmed Burns,
Roles of NPM2 in chromatin and nucleolar organization in oocytes and embryos.
2003,
Pubmed
,
Xenbase Cotten,
Massive phosphorylation distinguishes Xenopus laevis nucleoplasmin isolated from oocytes or unfertilized eggs.
1986,
Pubmed
,
Xenbase De La Fuente,
Major chromatin remodeling in the germinal vesicle (GV) of mammalian oocytes is dispensable for global transcriptional silencing but required for centromeric heterochromatin function.
2004,
Pubmed Dutta,
The crystal structure of nucleoplasmin-core: implications for histone binding and nucleosome assembly.
2001,
Pubmed Emsley,
Coot: model-building tools for molecular graphics.
2004,
Pubmed Goddard,
Software extensions to UCSF chimera for interactive visualization of large molecular assemblies.
2005,
Pubmed Hierro,
Electrostatic interactions at the C-terminal domain of nucleoplasmin modulate its chromatin decondensation activity.
2002,
Pubmed
,
Xenbase Hierro,
Structural and functional properties of Escherichia coli-derived nucleoplasmin. A comparative study of recombinant and natural proteins.
2001,
Pubmed
,
Xenbase Ito,
ATP-facilitated chromatin assembly with a nucleoplasmin-like protein from Drosophila melanogaster.
1996,
Pubmed
,
Xenbase Kissinger,
Rapid automated molecular replacement by evolutionary search.
1999,
Pubmed Kleinschmidt,
Co-existence of two different types of soluble histone complexes in nuclei of Xenopus laevis oocytes.
1985,
Pubmed
,
Xenbase Kleinschmidt,
Molecular characterization of a karyophilic, histone-binding protein: cDNA cloning, amino acid sequence and expression of nuclear protein N1/N2 of Xenopus laevis.
1986,
Pubmed
,
Xenbase Kleinschmidt,
Nucleosome assembly in vitro: separate histone transfer and synergistic interaction of native histone complexes purified from nuclei of Xenopus laevis oocytes.
1990,
Pubmed
,
Xenbase Laskey,
Nucleosomes are assembled by an acidic protein which binds histones and transfers them to DNA.
1978,
Pubmed
,
Xenbase Lee,
Crystal structure of human nucleophosmin-core reveals plasticity of the pentamer-pentamer interface.
2007,
Pubmed Leno,
Hyperphosphorylation of nucleoplasmin facilitates Xenopus sperm decondensation at fertilization.
1996,
Pubmed
,
Xenbase Luger,
Characterization of nucleosome core particles containing histone proteins made in bacteria.
1997,
Pubmed
,
Xenbase Namboodiri,
The crystal structure of Drosophila NLP-core provides insight into pentamer formation and histone binding.
2003,
Pubmed Namboodiri,
The structure and function of Xenopus NO38-core, a histone chaperone in the nucleolus.
2004,
Pubmed
,
Xenbase Okuwaki,
Function of nucleophosmin/B23, a nucleolar acidic protein, as a histone chaperone.
2001,
Pubmed Otwinowski,
Processing of X-ray diffraction data collected in oscillation mode.
1997,
Pubmed Philpott,
Nuclear chaperones.
2000,
Pubmed Philpott,
Sperm decondensation in Xenopus egg cytoplasm is mediated by nucleoplasmin.
1991,
Pubmed
,
Xenbase Philpott,
Nucleoplasmin remodels sperm chromatin in Xenopus egg extracts.
1992,
Pubmed
,
Xenbase Ramos,
Nucleoplasmin-mediated unfolding of chromatin involves the displacement of linker-associated chromatin proteins.
2005,
Pubmed
,
Xenbase Ramos,
Nucleoplasmin binds histone H2A-H2B dimers through its distal face.
2010,
Pubmed
,
Xenbase Robbins,
Two interdependent basic domains in nucleoplasmin nuclear targeting sequence: identification of a class of bipartite nuclear targeting sequence.
1991,
Pubmed
,
Xenbase Salvany,
Mutation of the small acidic tract A1 drastically reduces nucleoplasmin activity.
2004,
Pubmed
,
Xenbase Studier,
Protein production by auto-induction in high density shaking cultures.
2005,
Pubmed Taneva,
Activation of nucleoplasmin, an oligomeric histone chaperone, challenges its stability.
2008,
Pubmed Taneva,
A mechanism for histone chaperoning activity of nucleoplasmin: thermodynamic and structural models.
2009,
Pubmed
,
Xenbase Woodland,
The synthesis and storage of histones during the oogenesis of Xenopus laevis.
1977,
Pubmed
,
Xenbase Ye,
Defective S phase chromatin assembly causes DNA damage, activation of the S phase checkpoint, and S phase arrest.
2003,
Pubmed Zucker,
The histone H3/H4.N1 complex supplemented with histone H2A-H2B dimers and DNA topoisomerase I forms nucleosomes on circular DNA under physiological conditions.
1990,
Pubmed
,
Xenbase