Phosphate disruption and metal toxicity in Saccharomyces cerevisiae: Effects of RAD23 and the histone chaperone HPC2

The histone chaperone FACT plays an important role in facilitating nucleosome assembly and disassembly during transcription. FACT is a heterodimeric complex consisting of Spt16 and SSRP1. The N-terminal domain of Spt16 resembles an inactive aminopeptidase. How this domain contributes to the histone chaperone activity of FACT remains elusive. Here, the crystal structure of the N-terminal domain (NTD) of human Spt16 is reported at a resolution of 1.84 Å. The structure adopts an aminopeptidase-like fold similar to those of theSaccharomyces cerevisiaeandSchizosaccharomyces pombeSpt16 NTDs. Isothermal titration calorimetry analyses show that human Spt16 NTD binds histones H3/H4 with low-micromolar affinity, suggesting that Spt16 NTD may contribute to histone binding in the FACT complex. Surface-residue conservation and electrostatic analysis reveal a conserved acidic patch that may be involved in histone binding.

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Structure/Function Analysis of the Hif1 Histone Chaperone in Saccharomyces cerevisiae

10.32920/ryerson.14647209.v1 ◽

2021 ◽

Author(s):

Nora Saud Dannah

Keyword(s):

Saccharomyces Cerevisiae ◽

Chromosome Segregation ◽

Genome Stability ◽

Function Analysis ◽

Molecular Genetic ◽

Histone Chaperone ◽

Chromatin Assembly ◽

Biological Processes ◽

Genetic Approach ◽

Yeast Saccharomyces Cerevisiae

Understanding the regulation of chromatin structure is a vital aspect of molecular biology regarding its influences on biological processes such as DNA replication, transcription (gene expression), DNA repair, chromosome segregation and recombination. In the budding yeast Saccharomyces cerevisiae, a histone chaperone called Hif1 has been found in the nuclei as having a functional role in chromatin assembly. Hif1 is a homolog of the human protein NASP that is involved in the maintenance of genome stability. Previously, Hif1 has been shown to physically interact with Hat1, Hat2 and H3/H4 to form the NuB4 complex directly involved in chromatin assembly. A molecular genetic approach was conducted to determine which domain of Hif1 is involved in the interaction with the HAT1 complex.

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Coordinated Action of Nap1 and RSC in Disassembly of Tandem Nucleosomes

Molecular and Cellular Biology ◽

10.1128/mcb.00195-16 ◽

2016 ◽

Vol 36 (17) ◽

pp. 2262-2271 ◽

Cited By ~ 6

Author(s):

Rashmi Prasad ◽

Sheena D'Arcy ◽

Arjan Hada ◽

Karolin Luger ◽

Blaine Bartholomew

Keyword(s):

Saccharomyces Cerevisiae ◽

Mutational Analysis ◽

Histone Chaperone ◽

Histone Chaperones ◽

Content Type ◽

Chromatin Remodelers ◽

Coordinated Action

The SWI/SNF and RSC family of ATP-dependent chromatin remodelers disassembles nucleosomes by moving nucleosomes into the vicinity of adjoining nucleosomes. We found that the histone chaperone Nap1 efficiently promotes disassembly of adjacent nucleosomes with which RSC collides and not the disassembly of nucleosomes mobilized by RSC. Nap1 is specific to RSC, as it does not target SWI/SNF, its paralog inSaccharomyces cerevisiae. Extensive mutational analysis of Nap1 has revealed that Nap1 affinity for histones H2A-H2B and H3-H4 and its ability to displace histones from DNA are required for Nap1 to enhance RSC-mediated disassembly. Other histone chaperones, such as Vps75, that also bind histones are not able to enhance RSC-mediated disassembly. Our study suggests a mechanism by which Nap1 is recruited to actively transcribed regions and assists in the passage of the transcription complex through chromatin, and it provides a novel mechanism for the coordinated action of RSC and Nap1.

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Chaperone Control of the Activity and Specificity of the Histone H3 Acetyltransferase Rtt109

Molecular and Cellular Biology ◽

10.1128/mcb.00182-08 ◽

2008 ◽

Vol 28 (13) ◽

pp. 4342-4353 ◽

Cited By ~ 130

Author(s):

Jeffrey Fillingham ◽

Judith Recht ◽

Andrea C. Silva ◽

Bernhard Suter ◽

Andrew Emili ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Histone Acetyltransferase ◽

Histone H3 ◽

Histone Chaperone ◽

Genetic Interactions ◽

Whole Genome ◽

Genome Screen ◽

Associated Lesions

ABSTRACT Acetylation of Saccharomyces cerevisiae histone H3 on K56 by the histone acetyltransferase (HAT) Rtt109 is important for repairing replication-associated lesions. Rtt109 purifies from yeast in complex with the histone chaperone Vps75, which stabilizes the HAT in vivo. A whole-genome screen to identify genes whose deletions have synthetic genetic interactions with rtt109Δ suggests Rtt109 has functions in addition to DNA repair. We show that in addition to its known H3-K56 acetylation activity, Rtt109 is also an H3-K9 HAT, and we show that Rtt109 and Gcn5 are the only H3-K9 HATs in vivo. Rtt109's H3-K9 acetylation activity in vitro is enhanced strongly by Vps75. Another histone chaperone, Asf1, and Vps75 are both required for acetylation of lysine 9 on H3 (H3-K9ac) in vivo by Rtt109, whereas H3-K56ac in vivo requires only Asf1. Asf1 also physically interacts with the nuclear Hat1/Hat2/Hif1 complex that acetylates H4-K5 and H4-K12. We suggest Asf1 is capable of assembling into chromatin H3-H4 dimers diacetylated on both H4-K5/12 and H3-K9/56.

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Structure/Function Analysis of the Hif1 Histone Chaperone in Saccharomyces cerevisiae

10.32920/ryerson.14647209 ◽

2021 ◽

Author(s):

Nora Saud Dannah

Keyword(s):

Saccharomyces Cerevisiae ◽

Chromosome Segregation ◽

Genome Stability ◽

Function Analysis ◽

Molecular Genetic ◽

Histone Chaperone ◽

Chromatin Assembly ◽

Biological Processes ◽

Genetic Approach ◽

Yeast Saccharomyces Cerevisiae

Understanding the regulation of chromatin structure is a vital aspect of molecular biology regarding its influences on biological processes such as DNA replication, transcription (gene expression), DNA repair, chromosome segregation and recombination. In the budding yeast Saccharomyces cerevisiae, a histone chaperone called Hif1 has been found in the nuclei as having a functional role in chromatin assembly. Hif1 is a homolog of the human protein NASP that is involved in the maintenance of genome stability. Previously, Hif1 has been shown to physically interact with Hat1, Hat2 and H3/H4 to form the NuB4 complex directly involved in chromatin assembly. A molecular genetic approach was conducted to determine which domain of Hif1 is involved in the interaction with the HAT1 complex.

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Structural basis of nucleosome transcription mediated by Chd1 and FACT

Nature Structural & Molecular Biology ◽

10.1038/s41594-021-00578-6 ◽

2021 ◽

Author(s):

Lucas Farnung ◽

Moritz Ochmann ◽

Maik Engeholm ◽

Patrick Cramer

Keyword(s):

Saccharomyces Cerevisiae ◽

Dna Binding ◽

Rna Polymerase ◽

Rna Polymerase Ii ◽

Histone Chaperone ◽

Structural Basis ◽

Histone H2a ◽

Binding Region ◽

Chromatin Remodeler ◽

Pol Ii

AbstractEfficient transcription of RNA polymerase II (Pol II) through nucleosomes requires the help of various factors. Here we show biochemically that Pol II transcription through a nucleosome is facilitated by the chromatin remodeler Chd1 and the histone chaperone FACT when the elongation factors Spt4/5 and TFIIS are present. We report cryo-EM structures of transcribing Saccharomyces cerevisiae Pol II−Spt4/5−nucleosome complexes with bound Chd1 or FACT. In the first structure, Pol II transcription exposes the proximal histone H2A−H2B dimer that is bound by Spt5. Pol II has also released the inhibitory DNA-binding region of Chd1 that is poised to pump DNA toward Pol II. In the second structure, Pol II has generated a partially unraveled nucleosome that binds FACT, which excludes Chd1 and Spt5. These results suggest that Pol II progression through a nucleosome activates Chd1, enables FACT binding and eventually triggers transfer of FACT together with histones to upstream DNA.

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Histone chaperone Chz1 facilitates the disfavouring property of Spt16 to H2A.Z-containing genes in Saccharomyces cerevisiae

Biochemical Journal ◽

10.1042/bj20140186 ◽

2014 ◽

Vol 460 (3) ◽

pp. 387-397 ◽

Cited By ~ 5

Author(s):

Hongde Liu ◽

Kun Luo ◽

Zikai Zhou ◽

Yawen Mu ◽

Yakun Wan

Keyword(s):

Saccharomyces Cerevisiae ◽

Deletion Mutant ◽

Histone Chaperone ◽

Transcription Rate ◽

Pol Ii

Spt16 and Pol II associate at nucleosome-depleted regions and positively correlate with the transcription rate. Spt16 disfavours the Htz1-bound genes, and this discrimination is diminished in a Ch21-deletion mutant.

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