Histone chaperone networks shaping chromatin function Nat Rev Mol Cell Biol. 2017 Mar;18(3):141-158. doi: 10.1038/nrm.2016.159. ... We emphasize how chaperones cooperate in the histone chaperone network and via co-chaperone complexes to match histone supply with demand, thereby promoting proper nucleosome assembly and maintaining epigenetic ...
Histone chaperones build a network of escort functions Recent crystallographic studies have provided new insights into the relationships between histone chaperones and their cargo, the histones ...
Models of histone chaperone function illustrated as free-energy reaction diagrams. The change in free-energy is plotted along the reaction coordinate as the substrate (DNA and histones, middle) becomes the product (precipitate, left, or tetrasome, right). ... Closely associated both figuratively and literally, with the histones, is a network of ...
This review highlights the functional implication of the network of histone chaperones in shaping the chromatin function in the development of an organism. Seminal studies have reported embryonic lethality at different stages of embryogenesis upon perturbation of some of the chaperones, suggesting their essentiality in development.
Histone chaperones participate in the biogenesis, transportation, and deposition of histones. They contribute to processes impacted by nucleosomes including DNA replication, transcription, and epigenetic inheritance. In this issue, Carraro et al.1 reveal an interconnected chaperone network and a surprising function of histone chaperone DAXX in de novo deposition of H3.3K9me3.
Histone chaperones can also participate in the distribution of histone variants, thereby defining distinct chromatin landscapes of importance for genome function, stability, and cell identity. Here, we discuss our current knowledge of the known histone chaperones and their histone partners, focusing on histone H3 and its variants.
Histone chaperone network. The integration of histone chaperone functions to support histone dynamics across various cellular processes. Canonical histones. Core histone subtypes (H3.1, H3.2, H4, H2A and H2B) that are expressed in S phase of the cell cycle and mainly incorporated into nucleosomes in a DNA replication-dependent manner.
We identified DNAJC9 as a co-chaperone of MCM2 and TONSL that can substitute for ASF1. Our structure-function characterization reveals that DNAJC9 has both heat shock co-chaperone and histone chaperone functionalities, integrating ATP-dependent protein remodeling enzymes into the histone chaperone network to safeguard histone H3-H4 dimer integrity.
with histone chaperones that act early in the histone supply pathway (i.e., HAT1). Depletion of DNAJC9 leads to interesting redistributions of H3-H4 within the histone chaperone network. The au-thors propose an attractive model where DNAJC9 acts on histones at multiple stages of their metabolism. By engaging Hsp70, DNAJC9 guards histones’ struc-
There are two major types of histone chaperone classifications: i) by the type of histones they bind, and ii) by their role in assembly of new nucleosomes during replication or a function affecting nucleosomes in a replication-independent manner . FACT does not fit easily into a single category in this standard classification scheme.
In this issue, Carraro et al. 1 reveal an interconnected chaperone network and a surprising function of histone chaperone DAXX in de novo deposition of H3.3K9me3. The nucleosome, consisting of 147 bp of DNA wrapped around a histone octamer, is the basic repeat unit of the eukaryotic chromatin. ... To uncover the potential network of histone ...
A C. elegans ortholog of the SPT2 histone chaperone. We set out to test if SPT2 histone binding activity is relevant for chromatin structure and function in Metazoa. The nematode C. elegans has ...
Histone chaperone networks, including Hsc70 and chromatin assembly factor 1(CAF1), have been shown to guide H3.1 positioning and function . For this function, p53 appears to down-regulate nuclear phosphatidic acid (PA) levels, likely via its transcriptional activity, and exclude EZH2 from the H3.1 interactome . HspA8 is highly overexpressed in ...
To achieve these different functions, histones are handled by a network of histone chaperones for deposition, eviction, or recycling during replication and transcription (Typas, 2023). Arabidopsis ASF1 is involved in multiple interactions within this network.
To uncover the potential network of histone chaperones and their co-factors, Carraro et al. 1 employ triple SILAC-based quantitative mass spectrometry and compare the interactomes of several commonly known chaperones and their mutant counterparts defective of histone binding. Interestingly, most of the analyzed histone chaperones (ASF1a, ASF1b, DAXX, DNAJC9, HJURP, sNASP, MCM2, and TONSL ...
Histone chaperones are a group of proteins with diverse functions that are primarily involved in escorting histones to assemble nucleosomes and maintain the chromatin landscape. Whether distinct histone chaperone pathways control cell fate and whether they function using related mechanisms remain unclear. To address this, we performed a screen ...
Tight regulation of histone variant functions by histone chaperones is crucial for cell homeostasis and the prevention of tumorigenesis. The most compelling model is that a combination of factors determines a chaperone’s ability to influence the dynamics of a histone variant. ... Muller S, Almouzni G. A network of players in H3 histone ...
In order to find new members of the histone chaperone network and with an elegantly designed proteomic screen, Hammond et al. (2021) identify DNAJC9 collaborating with the well-characterized histone chaperones MCM2 and TONSL. They solve the crystal structure of the C-terminal histone-binding domain (HBD) of DNAJC9 in complex with the histone H3 ...
They contribute to processes impacted by nucleosomes including DNA replication, transcription, and epigenetic inheritance. In this issue, Carraro et al. 1 reveal an interconnected chaperone network and a surprising function of histone chaperone DAXX in de novo deposition of H3.3K9me3.
