scholarly journals Dual Roles of p300 in Chromatin Assembly and Transcriptional Activation in Cooperation with Nucleosome Assembly Protein 1 In Vitro

2002 ◽  
Vol 22 (9) ◽  
pp. 2974-2983 ◽  
Author(s):  
Hiroshi Asahara ◽  
Sophie Tartare-Deckert ◽  
Takeya Nakagawa ◽  
Tsuyoshi Ikehara ◽  
Fumiko Hirose ◽  
...  
Keyword(s):  
Transcriptional Activation ◽  
Chromatin Assembly ◽  
Micrococcal Nuclease ◽  
Histone H2a ◽  
Nucleosome Assembly ◽  
Nucleosome Assembly Protein ◽  
Nucleosome Assembly Protein 1 ◽  
Core Histones ◽  
Kix Domain

ABSTRACT In a yeast two-hybrid screen to identify proteins that bind to the KIX domain of the coactivator p300, we obtained cDNAs encoding nucleosome assembly protein 1 (NAP-1), a 60-kDa histone H2A-H2B shuttling protein that promotes histone deposition. p300 associates preferentially with the H2A-H2B-bound form of NAP-1 rather than with the unbound form of NAP-1. Formation of NAP-1-p300 complexes was found to increase during S phase, suggesting a potential role for p300 in chromatin assembly. In micrococcal nuclease and supercoiling assays, addition of p300 promoted efficient chromatin assembly in vitro in conjunction with NAP-1 and ATP-utilizing chromatin assembly and remodeling factor; this effect was dependent in part on the intrinsic histone acetyltransferase activity of p300. Surprisingly, NAP-1 potently inhibited acetylation of core histones by p300, suggesting that efficient assembly requires acetylation of either NAP-1 or p300 itself. As p300 acted cooperatively with NAP-1 in stimulating transcription from a chromatin template in vitro, our results suggest a dual role of NAP-1-p300 complexes in promoting chromatin assembly and transcriptional activation.

scholarly journals Histone Chaperone Nap1 Is a Major Regulator of Histone H2A-H2B Dynamics at the InducibleGALLocus

2016 ◽  
Vol 36 (8) ◽  
pp. 1287-1296 ◽  
Author(s):  
Xu Chen ◽  
Sheena D'Arcy ◽  
Catherine A. Radebaugh ◽  
Daniel D. Krzizike ◽  
Holli A. Giebler ◽  
...  
Keyword(s):  
Critical Role ◽  
Histone Chaperones ◽  
Histone H2a ◽  
Nucleosome Assembly ◽  
Content Type ◽  
Nucleosome Assembly Protein ◽  
Nucleosome Assembly Protein 1 ◽  
Histone Exchange

Histone chaperones, like nucleosome assembly protein 1 (Nap1), play a critical role in the maintenance of chromatin architecture. Here, we use theGALlocus inSaccharomyces cerevisiaeto investigate the influence of Nap1 on chromatin structure and histone dynamics during distinct transcriptional states. When theGALlocus is not expressed, cells lacking Nap1 show an accumulation of histone H2A-H2B but not histone H3-H4 at this locus. Excess H2A-H2B interacts with the linker DNA between nucleosomes, and the interaction is independent of the inherent DNA-binding affinity of H2A-H2B for these particular sequences as measuredin vitro. When theGALlocus is transcribed, excess H2A-H2B is reversed, and levels of all chromatin-bound histones are depleted in cells lacking Nap1. We developed anin vivosystem to measure histone exchange at theGALlocus and observed considerable variability in the rate of exchange across the locus in wild-type cells. We recapitulate this variability within vitronucleosome reconstitutions, which suggests a contribution of DNA sequence to histone dynamics. We also find that Nap1 is required for transcription-dependent H2A-H2B exchange. Altogether, these results indicate that Nap1 is essential for maintaining proper chromatin composition and modulating the exchange of H2A-H2Bin vivo.

scholarly journals Drosophila NAP-1 is a core histone chaperone that functions in ATP-facilitated assembly of regularly spaced nucleosomal arrays.

1996 ◽  
Vol 16 (6) ◽  
pp. 3112-3124 ◽  
Author(s):  
T Ito ◽  
M Bulger ◽  
R Kobayashi ◽  
J T Kadonaga
Keyword(s):  
Chromatin Assembly ◽  
Drosophila Embryo ◽  
Core Histone ◽  
In Vivo Studies ◽  
Nucleosome Assembly ◽  
Nucleosome Assembly Protein ◽  
Nucleosome Assembly Protein 1 ◽  
Core Histones ◽  
Assembly Factor

We describe the cloning and analysis of Drosophila nucleosome assembly protein 1 (dNAP-1), a core histone-binding protein that functions with other chromatin assembly activities in a Drosophila chromatin assembly factor 1-containing fraction (dCAF-1 fraction) in the ATP-facilitated assembly of regularly spaced nucleosomal arrays from purified core histones and DNA. Purified, recombinant dNAP-1 acts cooperatively with a factor(s) in the dCAF-1 fraction in the efficient and DNA replication-independent assembly of chromatin. In the presence of histone H1, the repeat length of the chromatin is similar to that of native chromatin from Drosophila embryos. By coimmunoprecipitation analysis, dNAP-1 was found to be associated with histones H2A and H2B in a crude whole-embryo extract, which suggests that dNAP-1 is bound to the histones in vivo. Studies of the localization of dNAP-1 in the Drosophila embryo revealed that the factor is present in the nucleus during S phase and is predominantly cytoplasmic during G2 phase. These data suggest that NAP-1 acts as a core histone shuttle which delivers the histones from the cytoplasm to the chromatin assembly machinery in the nucleus. Thus, NAP-1 appears to be one component of a multifactor chromatin assembly machinery that mediates the ATP-facilitated assembly of regularly spaced nucleosomal arrays.

Assembly states of the nucleosome assembly protein 1 (NAP-1) revealed by sedimentation velocity and non-denaturing MS

2011 ◽  
Vol 436 (1) ◽  
pp. 101-112 ◽  
Author(s):  
Masanori Noda ◽  
Susumu Uchiyama ◽  
Adam R. McKay ◽  
Akihiro Morimoto ◽  
Shigeki Misawa ◽  
...  
Keyword(s):  
Protein Interactions ◽  
Electrostatic Interactions ◽  
Analytical Ultracentrifugation ◽  
Three Dimensional ◽  
Sedimentation Velocity ◽  
Dimensional Structure ◽  
Histone H2a ◽  
Nucleosome Assembly ◽  
Nucleosome Assembly Protein ◽  
Nucleosome Assembly Protein 1

Proteins often exist as ensembles of interconverting states in solution which are often difficult to quantify. In the present manuscript we show that the combination of MS under nondenaturing conditions and AUC-SV (analytical ultracentrifugation sedimentation velocity) unambiguously clarifies a distribution of states and hydrodynamic shapes of assembled oligomers for the NAP-1 (nucleosome assembly protein 1). MS established the number of associated units, which was utilized as input for the numerical analysis of AUC-SV profiles. The AUC-SV analysis revealed that less than 1% of NAP-1 monomer exists at the micromolar concentration range and that the basic assembly unit consists of dimers of yeast or human NAP-1. These dimers interact non-covalently to form even-numbered higher-assembly states, such as tetramers, hexamers, octamers and decamers. MS and AUC-SV consistently showed that the formation of the higher oligomers was suppressed with increasing ionic strength, implicating electrostatic interactions in the formation of higher oligomers. The hydrodynamic shapes of the NAP-1 tetramer estimated from AUC-SV agreed with the previously proposed assembly models built using the known three-dimensional structure of yeast NAP-1. Those of the hexamer and octamer could be represented by new models shown in the present study. Additionally, MS was used to measure the stoichiometry of the interaction between the human NAP-1 dimer and the histone H2A–H2B dimer or H3–H4 tetramer. The present study illustrates a rigorous procedure for the analysis of protein assembly and protein–protein interactions in solution.

scholarly journals Nucleosome Assembly Protein 1 Exchanges Histone H2A-H2B Dimers and Assists Nucleosome Sliding

2004 ◽  
Vol 280 (3) ◽  
pp. 1817-1825 ◽  
Author(s):  
Young-Jun Park ◽  
Jayanth V. Chodaparambil ◽  
Yunhe Bao ◽  
Steven J. McBryant ◽  
Karolin Luger
Keyword(s):  
Histone H2a ◽  
Nucleosome Assembly ◽  
Nucleosome Assembly Protein ◽  
Nucleosome Assembly Protein 1 ◽  
Nucleosome Sliding

scholarly journals Reconstitution of Drosophila and human chromatins by wheat germ cell-free co-expression system

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Kei-ichi Okimune ◽  
Szilvia K. Nagy ◽  
Shogo Hataya ◽  
Yaeta Endo ◽  
Taichi E. Takasuka
Keyword(s):  
Protein Expression ◽  
Germ Cell ◽  
Chromatin Remodeling ◽  
Wheat Germ ◽  
Chromatin Assembly ◽  
Micrococcal Nuclease ◽  
In Vitro Translation ◽  
Free Protein ◽  
Core Histones

Abstract Background Elaboration of the epigenetic regulation of chromatin is a long-standing aim in molecular and cellular biology. Hence, there is a great demand for the development of in vitro methods to reconstitute chromatin that can be used directly for biochemical assays. The widely used wheat germ cell-free protein expression method provides broad applications to investigate the function and structure of eukaryotic proteins. Such advantages, including high translation efficiency, flexibility, and possible automatization, are beneficial for achieving native-like chromatin substrates for in vitro studies. Results We describe a novel, single-step in vitro chromatin assembly method by using the wheat germ cell-free protein synthesis. We demonstrated that both Drosophila and human chromatins can be reconstituted in the course of the in vitro translation of core histones by the addition of chromatin assembly factors, circular plasmid, and topoisomerase I in an ATP-dependent manner. Drosophila chromatin assembly was performed in 4 h at 26 °C, in the presence of premixed mRNAs encoding the core histones, dAcf1/dISWI chromatin remodeling complex, and nucleosome assembly protein, dNAP1. Similarly, the human chromatin was assembled by co-expressing the human core histones with Drosophila chromatin remodeling factor, dISWI, and chromatin chaperone, dNLP, for 6 h at 26 °C. The presence of reconstituted chromatin was monitored by DNA supercoiling assay, also the regular spacing of nucleosomes was assessed by Micrococcal nuclease assay. Furthermore, Drosophila linker histone H1-containing chromatin was reconstituted, affirming that the in vitro assembled chromatin is suitable for downstream applications. Conclusions The method described in this study allows the assembly of Drosophila and human chromatins, possibly in native-like form, by using a wheat germ cell-free protein expression. Although both chromatins were reconstituted successfully, there were unexpected differences with respect to the required ratio of histone-coding mRNAs and the reaction time. Overall, our new in vitro chromatin reconstitution method will aid to characterize the unrevealed structure, function, and regulation of chromatin dynamics.

scholarly journals The Nucleosome Assembly Activity of NAP1 Is Enhanced by Alien

2007 ◽  
Vol 27 (10) ◽  
pp. 3557-3568 ◽  
Author(s):  
Maren Eckey ◽  
Wei Hong ◽  
Maria Papaioannou ◽  
Aria Baniahmad
Keyword(s):  
Gene Expression ◽  
Chromatin Immunoprecipitation ◽  
Hormone Receptors ◽  
Nucleosome Assembly ◽  
Nucleosome Assembly Protein ◽  
Nucleosome Assembly Protein 1 ◽  
Dna Template ◽  
Assembly Activity

ABSTRACT The assembly of nucleosomes into chromatin is essential for the compaction of DNA and inactivation of the DNA template to modulate and repress gene expression. The nucleosome assembly protein 1, NAP1, assembles nucleosomes independent of DNA synthesis and was shown to enhance coactivator-mediated gene expression, suggesting a role for NAP1 in transcriptional regulation. Here, we show that Alien, known to harbor characteristics of a corepressor of nuclear hormone receptors such as of the vitamin D receptor (VDR), binds in vivo and in vitro to NAP1 and modulates its activity by enhancing NAP1-mediated nucleosome assembly on DNA. Furthermore, Alien reduces the accessibility of the histones H3 and H4 for NAP1-promoted assembly reaction. This indicates that Alien sustains and reinforces the formation of nucleosomes. Employing deletion mutants of Alien suggests that different regions of Alien are involved in enhancement of NAP1-mediated nucleosome assembly and in inhibiting the accessibility of the histones H3 and H4. In addition, we provide evidence that Alien is associated with chromatin and with micrococcus nuclease-prepared nucleosome fractions and interacts with the histones H3 and H4. Furthermore, chromatin immunoprecipitation and reimmunoprecipitation experiments suggest that NAP1 and Alien localize to the endogenous CYP24 promoter in vivo, a VDR target gene. Based on these findings, we present here a novel pathway linking corepressor function with nucleosome assembly activity.

scholarly journals Association States of Nucleosome Assembly Protein 1 and Its Complexes with Histones

2005 ◽  
Vol 280 (16) ◽  
pp. 15690-15699 ◽  
Author(s):  
Katalin Fejes Tóth ◽  
Jacek Mazurkiewicz ◽  
Karsten Rippe
Keyword(s):  
Nuclear Import ◽  
Analytical Ultracentrifugation ◽  
Nucleosome Assembly ◽  
Nucleosome Assembly Protein ◽  
Nucleosome Assembly Protein 1 ◽  
Core Histones ◽  
A Cell ◽  
Cycle Dependent ◽  
Equilibrium Dissociation ◽  
Prevalent Species

The histone chaperone NAP1 is a carrier of histones during nuclear import, nucleosome assembly, and chromatin remodeling. Analytical ultracentrifugation was used to determine the association states of NAP1 alone and in complexes with core histones. In addition, the concentration dependence of the association was quantified by determining the equilibrium dissociation constant between different NAP1 species. At physiological protein and salt concentrations the prevalent species were the NAP1 dimer and octamer. These were also the association states found to interact with histones in a stoichiometry of one NAP1 monomer per histone. Based on these results a model for a cell cycle-dependent shift of the NAP1 dimer-octamer equilibrium is proposed that reflects different biological functions of NAP1.

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