Histone H3K27 methylation–mediated repression of Hairy regulates insect developmental transition by modulating ecdysone biosynthesis

Insect development is cooperatively orchestrated by the steroid hormone ecdysone and juvenile hormone (JH). The polycomb repressive complex 2 (PRC2)–mediated histone H3K27 trimethylation (H3K27me3) epigenetically silences gene transcription and is essential for a range of biological processes, but the functions of H3K27 methylation in insect hormone action are poorly understood. Here, we demonstrate that H3K27 methylation–mediated repression of Hairy transcription in the larval prothoracic gland (PG) is required for ecdysone biosynthesis in Bombyx and Drosophila. H3K27me3 levels in the PG are dynamically increased during the last larval instar. H3K27me3 reduction induced by the down-regulation of PRC2 activity via inhibitor treatment in Bombyx or PG-specific knockdown of the PRC2 component Su(z)12 in Drosophila diminishes ecdysone biosynthesis and disturbs the larval–pupal transition. Mechanistically, H3K27 methylation targets the JH signal transducer Hairy to repress its transcription in the PG; PG-specific knockdown or overexpression of the Hairy gene disrupts ecdysone biosynthesis and developmental transition; and developmental defects caused by PG-specific Su(z)12 knockdown can be partially rescued by Hairy down-regulation. The application of JH mimic to the PG decreases both H3K27me3 levels and Su(z)12 expression. Altogether, our study reveals that PRC2-mediated H3K27 methylation at Hairy in the PG during the larval period is required for ecdysone biosynthesis and the larval–pupal transition and provides insights into epigenetic regulation of the crosstalk between JH and ecdysone during insect development.

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Antagonistic roles of Polycomb repression and Notch signaling in the maintenance of somatic cell fate in C. elegans.

10.1101/055137 ◽

2016 ◽

Author(s):

Ringo Pueschel ◽

Francesca Coraggio ◽

Alisha Marti ◽

Peter Meister

Keyword(s):

Notch Signaling ◽

Cell Fate ◽

Ectopic Expression ◽

Epigenetic Mark ◽

Cell Plasticity ◽

Cell Therapies ◽

Polycomb Repressive Complex 2 ◽

C Elegans ◽

H3k27 Methylation ◽

Histone H3k27

AbstractReprogramming of somatic cells in intact nematodes allows characterization of cell plasticity determinants, which knowledge is crucial for regenerative cell therapies. By inducing muscle or endoderm transdifferentiation by the ectopic expression of selector transcription factors, we show that cell fate is remarkably robust in fully differentiated larvae. This stability depends on the presence of the Polycomb-associated histone H3K27 methylation, but not H3K9 methylation: in the absence of this epigenetic mark, many cells can be transdifferentiated which correlates with definitive developmental arrest. A candidate RNAi screen unexpectedly uncovered that knock-down of somatic NotchLIN-12 signaling rescues this larval arrest. Similarly in a wild-type context, genetically increasing NotchLIN-12 signaling renders a fraction of the animals sensitive to induced transdifferentiation. This reveals an antagonistic role of the Polycomb repressive complex 2 stabilizing cell fate and Notch signaling enhancing cell plasticity.

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Normal Patterns of Histone H3K27 Methylation Require the Histone Variant H2A.Z in Neurospora crassa

Genetics ◽

10.1534/genetics.120.303442 ◽

2020 ◽

Vol 216 (1) ◽

pp. 51-66 ◽

Cited By ~ 2

Author(s):

Abigail J. Courtney ◽

Masayuki Kamei ◽

Aileen R. Ferraro ◽

Kexin Gai ◽

Qun He ◽

...

Keyword(s):

Neurospora Crassa ◽

Embryonic Stem ◽

Histone Variant ◽

Genetic Studies ◽

Polycomb Repressive Complex 2 ◽

H3k27 Methylation ◽

Experimental Systems ◽

Polycomb Repression ◽

Histone H3k27 ◽

A Subunit

Neurospora crassa contains a minimal Polycomb repression system, which provides rich opportunities to explore Polycomb-mediated repression across eukaryotes and enables genetic studies that can be difficult in plant and animal systems. Polycomb Repressive Complex 2 is a multi-subunit complex that deposits mono-, di-, and trimethyl groups on lysine 27 of histone H3, and trimethyl H3K27 is a molecular marker of transcriptionally repressed facultative heterochromatin. In mouse embryonic stem cells and multiple plant species, H2A.Z has been found to be colocalized with H3K27 methylation. H2A.Z is required for normal H3K27 methylation in these experimental systems, though the regulatory mechanisms are not well understood. We report here that Neurospora crassa mutants lacking H2A.Z or SWR-1, the ATP-dependent histone variant exchanger, exhibit a striking reduction in levels of H3K27 methylation. RNA-sequencing revealed downregulation of eed, encoding a subunit of PRC2, in an hH2Az mutant compared to wild type, and overexpression of EED in a ΔhH2Az;Δeed background restored most H3K27 methylation. Reduced eed expression leads to region-specific losses of H3K27 methylation, suggesting that differential dependence on EED concentration is critical for normal H3K27 methylation at certain regions in the genome.

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Down-regulation of UDP-glucuronic Acid Biosynthesis Leads to Swollen Plant Cell Walls and Severe Developmental Defects Associated with Changes in Pectic Polysaccharides

Journal of Biological Chemistry ◽

10.1074/jbc.m111.255695 ◽

2011 ◽

Vol 286 (46) ◽

pp. 39982-39992 ◽

Cited By ~ 59

Author(s):

Rebecca Reboul ◽

Claudia Geserick ◽

Martin Pabst ◽

Beat Frey ◽

Doris Wittmann ◽

...

Keyword(s):

Plant Cell ◽

Cell Walls ◽

Glucuronic Acid ◽

Plant Cell Walls ◽

Acid Biosynthesis ◽

Down Regulation ◽

Pectic Polysaccharides ◽

Developmental Defects

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Histone H3K27 methylation modulates the dynamics of FANCD2 on chromatin to facilitate NHEJ and genome stability

Journal of Cell Science ◽

10.1242/jcs.215525 ◽

2018 ◽

Vol 131 (12) ◽

pp. jcs215525 ◽

Cited By ~ 8

Author(s):

Ye Zhang ◽

Jian-Feng Chang ◽

Jin Sun ◽

Lu Chen ◽

Xiao-Mei Yang ◽

...

Keyword(s):

Genome Stability ◽

H3k27 Methylation ◽

Histone H3k27

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Identification of a PRC2 Accessory Subunit Required for Subtelomeric H3K27 Methylation in Neurospora crassa

Molecular and Cellular Biology ◽

10.1128/mcb.00003-20 ◽

2020 ◽

Vol 40 (11) ◽

Author(s):

Kevin J. McNaught ◽

Elizabeth T. Wiles ◽

Eric U. Selker

Keyword(s):

Neurospora Crassa ◽

Transcriptional Repression ◽

Sequence Similarity ◽

Model Organism ◽

Content Type ◽

Polycomb Repressive Complex 2 ◽

H3k27 Methylation ◽

Accessory Subunit ◽

Genomic Regions ◽

Similarity Searches

ABSTRACT Polycomb repressive complex 2 (PRC2) catalyzes methylation of histone H3 at lysine 27 (H3K27) in genomic regions of most eukaryotes and is critical for maintenance of the associated transcriptional repression. However, the mechanisms that shape the distribution of H3K27 methylation, such as recruitment of PRC2 to chromatin and/or stimulation of PRC2 activity, are unclear. Here, using a forward genetic approach in the model organism Neurospora crassa, we identified two alleles of a gene, NCU04278, encoding an unknown PRC2 accessory subunit (PAS). Loss of PAS resulted in losses of H3K27 methylation concentrated near the chromosome ends and derepression of a subset of associated subtelomeric genes. Immunoprecipitation followed by mass spectrometry confirmed reciprocal interactions between PAS and known PRC2 subunits, and sequence similarity searches demonstrated that PAS is not unique to N. crassa. PAS homologs likely influence the distribution of H3K27 methylation and underlying gene repression in a variety of fungal lineages.

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Epigenetic Remodeling through Downregulation of Polycomb Repressive Complex 2 Mediates Chemotherapy Resistance in Testicular Germ Cell Tumors

Cancers ◽

10.3390/cancers11060796 ◽

2019 ◽

Vol 11 (6) ◽

pp. 796 ◽

Cited By ~ 5

Author(s):

Ratnakar Singh ◽

Zeeshan Fazal ◽

Andrea K. Corbet ◽

Emmanuel Bikorimana ◽

Jennifer C. Rodriguez ◽

...

Keyword(s):

Germ Cell ◽

Cisplatin Resistance ◽

Germ Cell Tumors ◽

Parental Origin ◽

Testicular Germ Cell Tumors ◽

Polycomb Repressive Complex ◽

Testicular Germ Cell ◽

Polycomb Repressive Complex 2 ◽

H3k27 Methylation ◽

Resistant Cells

A greater understanding of the hypersensitivity and curability of testicular germ cell tumors (TGCTs) has the potential to inform strategies to sensitize other solid tumors to conventional chemotherapies. The mechanisms of cisplatin hypersensitivity and resistance in embryonal carcinoma (EC), the stem cells of TGCTs, remain largely undefined. To study the mechanisms of cisplatin resistance we generated a large panel of independently derived, acquired resistant clones from three distinct parental EC models employing a protocol designed to match standard of care regimens of TGCT patients. Transcriptomics revealed highly significant expression changes shared between resistant cells regardless of their parental origin. This was dominated by a highly significant enrichment of genes normally repressed by H3K27 methylation and the polycomb repressive complex 2 (PRC2) which correlated with a substantial decrease in global H3K27me3, H2AK119 ubiquitination, and expression of BMI1. Importantly, repression of H3K27 methylation with the EZH2 inhibitor GSK-126 conferred cisplatin resistance to parental cells while induction of H3K27 methylation with the histone lysine demethylase inhibitor GSK-J4 resulted in increased cisplatin sensitivity to resistant cells. A gene signature based on H3K27me gene enrichment was associated with an increased rate of recurrent/progressive disease in testicular cancer patients. Our data indicates that repression of H3K27 methylation is a mechanism of cisplatin acquired resistance in TGCTs and that restoration of PRC2 complex function is a viable approach to overcome treatment failure.

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CATACOMB: An endogenous inducible gene that antagonizes H3K27 methylation activity of Polycomb repressive complex 2 via an H3K27M-like mechanism

Science Advances ◽

10.1126/sciadv.aax2887 ◽

2019 ◽

Vol 5 (7) ◽

pp. eaax2887 ◽

Cited By ~ 25

Author(s):

Andrea Piunti ◽

Edwin R. Smith ◽

Marc A. J. Morgan ◽

Michal Ugarenko ◽

Natalia Khaltyan ◽

...

Keyword(s):

Dna Methylation ◽

Biochemical Characterization ◽

Endometrial Stromal Sarcoma ◽

Polycomb Repressive Complex ◽

Polycomb Repressive Complex 2 ◽

H3k27 Methylation ◽

Inhibitory Function ◽

Methionine Residue ◽

Stromal Sarcoma ◽

A Subunit

Using biochemical characterization of fusion proteins associated with endometrial stromal sarcoma, we identified JAZF1 as a new subunit of the NuA4 acetyltransferase complex and CXORF67 as a subunit of the Polycomb Repressive Complex 2 (PRC2). Since CXORF67’s interaction with PRC2 leads to decreased PRC2-dependent H3K27me2/3 deposition, we propose a new name for this gene:CATACOMB(catalytic antagonist of Polycomb; official gene name:EZHIP). We mapCATACOMB’sinhibitory function to a short highly conserved region and identify a single methionine residue essential for diminution of H3K27me2/3 levels. Remarkably, the amino acid sequence surrounding this critical methionine resembles the oncogenic histone H3 Lys27-to-methionine (H3K27M) mutation found in high-grade pediatric gliomas. AsCATACOMBexpression is regulated through DNA methylation/demethylation, we proposeCATACOMBas the potential interlocutor between DNA methylation and PRC2 activity. We raise the possibility that similar regulatory mechanisms could exist for other methyltransferase complexes such as Trithorax/COMPASS.

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