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Series GSE150758 Query DataSets for GSE150758
Status Public on Jan 05, 2021
Title IMITATION SWITCH is required for normal chromatin structure and gene repression in PRC2 target domains
Organism Neurospora crassa
Experiment type Expression profiling by high throughput sequencing
Genome binding/occupancy profiling by high throughput sequencing
Summary Polycomb Group (PcG) proteins are part of an epigenetic cell memory system that plays essential roles in multicellular development, stem cell biology, X-chromosome inactivation, and cancer. In animals, plants, and many fungi, Polycomb Repressive Complex 2 (PRC2) catalyzes trimethylation of histone H3 lysine 27 (H3K27me3) to assemble transcriptionally repressed facultative heterochromatin. PRC2 is structurally and functionally conserved in the model fungus Neurospora crassa, and recent work in this organism has generated insights into PRC2 control and function. To identify new components of the facultative heterochromatin pathway, we performed a targeted screen of Neurospora deletion strains lacking individual ATP-dependent chromatin remodeling enzymes. We found the Neurospora homolog of IMITATION SWITCH (ISW) is critical for normal transcriptional repression, nucleosome organization, and establishment of typical histone methylation patterns in facultative heterochromatin domains. We also found that stable interaction between PRC2 and chromatin depends on ISW. A functional ISW ATPase domain is required for gene repression and H3K27 methylation. ISW homologs interact with accessory proteins to form multiple complexes with distinct functions. Using proteomics and molecular approaches, we identified three distinct Neurospora ISW-containing complexes. A triple mutant lacking three ISW-accessory factors and disrupting multiple ISW complexes led to widespread upregulation of PRC2 target genes and altered H3K27 methylation patterns, similar to an ISW-deficient strain. Taken together, our data show that ISW is a key component of the facultative heterochromatin pathway in Neurospora and that distinct ISW complexes perform an apparently overlapping role to regulate chromatin structure and gene repression at PRC2 target domains.
Overall design RNA-seq, MNAse-seq and ChIP-seq to compare wild type and mutant phenotypes
Contributor(s) Lewis Z, Kamei M, Ferraro A, Bar-Peled Y, Ameri AJ
Citation(s) 33468665
NIH grant(s)
Grant ID Grant title Affiliation Name
R01 GM132644 Transcriptional repression by Polycomb Repressive Complex 2 UNIVERSITY OF GEORGIA RESEARCH FOUNDATION, INC Zachary Lewis
Submission date May 18, 2020
Last update date Jun 02, 2022
Contact name Zachary A Lewis
Organization name University of Georgia
Department Microbiology
Lab Lewis
Street address 1000 Cedar St. Biosciences Bldg
City Athens
State/province GA
ZIP/Postal code 30602
Country USA
Platforms (1)
GPL20660 Illumina NextSeq 500 (Neurospora crassa)
Samples (94)
GSM4558135 111-37 WT rep 1.1
GSM4558136 111-38 WT rep 2.1
GSM4558137 111-39 WT rep 3.1
BioProject PRJNA633527
SRA SRP262144

Download family Format
SOFT formatted family file(s) SOFTHelp
MINiML formatted family file(s) MINiMLHelp
Series Matrix File(s) TXTHelp

Supplementary file Size Download File type/resource
GSE150758_GeoCountMatrix_RNAseq.txt.gz 388.5 Kb (ftp)(http) TXT
GSE150758_GeoCountMatrix_Revision_11_13_2020.txt.gz 941.3 Kb (ftp)(http) TXT
GSE150758_RAW.tar 572.9 Mb (http)(custom) TAR (of BW, TDF)
SRA Run SelectorHelp
Raw data are available in SRA
Processed data provided as supplementary file
Processed data are available on Series record

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