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Series GSE82222 Query DataSets for GSE82222
Status Public on Oct 27, 2016
Title Neurospora crassa genome organization requires subtelomeric facultative heterochromatin
Organism Neurospora crassa
Experiment type Other
Genome binding/occupancy profiling by high throughput sequencing
Expression profiling by high throughput sequencing
Summary Facultative heterochromatin in the filamentous fungus Neurospora crassa is identified by the repressive histone mark H3K27me3 and is primarily subtelomeric, while constitutive heterochromatin, marked by the DIM-5-catalzyed H3K9me3, is found at centromeres, telomeres, and smaller dispersed regions. In strains lacking constitutive heterochromatin (e.g., Δdim-5), H3K27me2/3 relocalizes to the regions formerly marked by H3K9me3. H3K27me3 is catalyzed by the SET-7 histone methyltransferase subunit of the Polycomb Repressive Complex 2 (PRC2); another PRC2 member, Neurospora p55 (NPF) regulates subtelomeric H3K27me2/3. Despite the de-repression of >70 genes, a Δset-7 strain has no distinguishable phenotype. To investigate the facultative heterochromatin contribution to genome organization, we performed high-throughput “chromosome conformation capture” (Hi-C) on mutants with impacted H3K27me2/3 deposition. A Δset-7 strain has decreased inter-/intra-subtelomeric contacts among others; this pattern is mirrored in a Δnpf strain, which lacks subtelomeric H3K27me3. In a Δset-7 strain, telomere bundles were often uncoupled from the nuclear membrane and de-repressed genes were subtelomeric. The chromosome conformation of a Δset-7;Δdim-5 double mutant was similar to Δset-7, suggesting that facultative heterochromatin relocalization does not compensate for H3K9me3 loss and rescue the Neurospora genome organization in strains with defective constitutive heterochromatin.
 
Overall design Hi-C: We analyzed a total of three strains of Neurospora crassa by chromatin conformation capture followed by high throughput sequencing (Hi-C). Each strain has two replicates. Strains were grown from conidia ~4 hours, crosslinked, and conidia were made into spheroplasts. Genomic DNA from spheroplasts was digested with HindIII, ends were filled in with dNTPs (including biotin-conjugated dCTP), blunt ends were ligated, crosslinks were reversed, DNA was soniciated, ligation products were purified with streptavidin beads, and libraries were prepared for sequencing. The datasets of wild type strain, NMF39 - deposited in GEO sebmission GSE71024, serves as the reference for the mutants deficient in facultative heterochromatin formation (N4718 delta set-7, N4721 delta npf, and N5542 delta set-7;delta dim-5).

ChIP-seq: We analyzed two strains of Neurospora crassa (control strain: WT N3752, test strain delta npf N4721) by Chromatin Immunoprecipitation for the histone mark H3K27me3. Strains were grown, crosslinked, lysed, the histone mark H3K27me3 was immunopurified, and associated DNA was sequenced).

RNA-seq: We analyzed a total of five strains (four different genetic backgrounds) by poly-A+ mRNA-sequencing for gene expression changes by monitoring poly-adenylated messenger RNA levels. A wild type strain (N3752) serves as the reference strain, and the strains N4718 and N4730 (delta set-7), N4721 (delta npf), and N5916 (delta set-7;delta dim-5) served as the test strains.

Please note that all python scripts (".py.txt" files) are provided as series supplementary file.
 
Contributor(s) Klocko AD, Ormsby T, Galazka JM, Uesaka M, Leggett N, Honda S, Freitag M, Selker EU
Citation(s) 27856763, 32946564
NIH grant(s)
Grant ID Grant title Affiliation Name
R01 GM035690 GENETIC ASPECTS OF DNA METHYLATION: Genetic Aspects of DNA Methylation: Genetic Aspects of DNA Methylation: Genetic Aspects of DNA Methylation: Genetic Aspects of DNA Methylation UNIVERSITY OF OREGON Eric U. SELKER
R01 GM093061 Control and Function of Histone H3 Lysine 27 Methylation in Neurospora UNIVERSITY OF OREGON Eric U. SELKER
R01 GM097637 Assembly and Maintenance of Centromeres in Filamentous Fungi OREGON STATE UNIVERSITY Freitag
F32 GM097821 Genetic analysis of DNA methylation in Neurospora crassa UNIVERSITY OF OREGON Andrew David Klocko
Submission date Jun 03, 2016
Last update date Oct 26, 2020
Contact name Andrew David Klocko
E-mail(s) aklocko@uccs.edu
Phone 719-255-3255
Organization name University of Colorado Colorado Springs
Department Chemistry and Biochemistry
Lab Klocko
Street address 278 Centennial Hall, 1420 Austin Bluffs Pkwy
City Colorado Springs
State/province Colorado
ZIP/Postal code 80918
Country USA
 
Platforms (2)
GPL20660 Illumina NextSeq 500 (Neurospora crassa)
GPL20705 Illumina HiSeq 2500 (Neurospora crassa)
Samples (16)
GSM2186732 NMF39_WildType_HiC (reanalyzed)
GSM2186733 N4718_set7_HiC
GSM2186734 N4721_npf_HiC
Relations
BioProject PRJNA324378
SRA SRP076095

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
GSE82222_Dataset_S1_4X-changed-genes_WT-v-set7.xlsx 17.4 Kb (ftp)(http) XLSX
GSE82222_Dataset_S2_4X-changed-genes_WT-v-npf.xlsx 80.7 Kb (ftp)(http) XLSX
GSE82222_Dataset_S3_4X-changed-genes_WT-v-set7dim5.xlsx 23.3 Kb (ftp)(http) XLSX
GSE82222_K9-K27_Quant.py.txt.gz 1.4 Kb (ftp)(http) TXT
GSE82222_K9-K27only_Quant.py.txt.gz 1.5 Kb (ftp)(http) TXT
GSE82222_RAW.tar 1.6 Gb (http)(custom) TAR (of BCF, TDF, TXT)
GSE82222_count_links_K27marked.py.txt.gz 1.1 Kb (ftp)(http) TXT
GSE82222_hicEigenvectorAnalysis.py.txt.gz 1.1 Kb (ftp)(http) TXT
GSE82222_hicEigenvector_singleLG.py.txt.gz 607 b (ftp)(http) TXT
GSE82222_hicPearsonCorrelationHeatmap.py.txt.gz 978 b (ftp)(http) TXT
GSE82222_neurospora_crassa_or74a_12_genome_FIXED.fasta.gz 11.3 Mb (ftp)(http) FASTA
GSE82222_neurospora_crassa_or74a_12_transcripts_FIXED.gtf.gz 755.6 Kb (ftp)(http) GTF
GSE82222_plotInterTelomeres.py.txt.gz 1.7 Kb (ftp)(http) TXT
GSE82222_plotIntraTelomeres.py.txt.gz 1.6 Kb (ftp)(http) TXT
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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