Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Default DNA Methylation is Preceded by Broad, Low-Level Transcription in Fetal Male Germ Cells and Is Inversely Patterned by Dynamic H3K4 Methylation (ChIP-chip and MIRA-chip)

ABSTRACT: To understand what dictates the emerging patterns of de novo DNA methylation, we mapped DNA methylation, chromatin, and transcription changes in purified fetal mouse germ cells using MIRA-chip, ChIP-chip, and strand-specific RNA-seq, respectively. De novo methylation occurred without any apparent trigger from preexisting repressing chromatin marks but was preceded by broad, low-level transcription along the entire genome in prospermatogonia. Only distinct short sequences remained unmethylated, precisely aligned with constitutive or emerging peaks of H3K4me2. Establishment of methylation at differentially methylated regions (DMRs) of imprinted genes, CpG islands, and IAPs followed these same default rules. Transcription run-through occurred at paternal DMRs with no- or diminishing H3K4me2 peaks. Maternal DMRs remained unmethylated among highly methylated DNA at precisely aligned H3K4me2 peaks with transcription initiating at least in one strand. Our results suggest that the pattern of de novo DNA methylation in prospermatogonia is dictated by opposing actions of broad, low-level transcription and dynamic patterns of active chromatin. ChIP-chip and MIRA-chip were performed to map histone modifications and DNA methylation at different devlopmental time points in germ cells and somatic cells along known imprinted domains and control regions, using custom NimbleGen tiling arrays.

ORGANISM(S): Mus musculus

SUBMITTER: Xiwei Wu

PROVIDER: E-GEOD-45836 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

De novo DNA methylation in the male germ line occurs by default but is excluded at sites of H3K4 methylation.

Singh Purnima P Li Arthur X AX Tran Diana A DA Oates Nathan N Kang Eun-Rim ER Wu Xiwei X Szabó Piroska E PE

Cell reports 20130627 1

To understand what dictates the emerging patterns of de novo DNA methylation in the male germline, we mapped DNA methylation, chromatin, and transcription changes in purified fetal mouse germ cells by using methylated CpG island recovery assay (MIRA)-chip, chromatin immunoprecipitation (ChIP)-chip, and strand-specific RNA deep sequencing, respectively. Global de novo methylation occurred by default in prospermatogonia without any apparent trigger from preexisting repressive chromatin marks but w ...[more]

PMID: 23810559

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Dataset Information

Default DNA Methylation is Preceded by Broad, Low-Level Transcription in Fetal Male Germ Cells and Is Inversely Patterned by Dynamic H3K4 Methylation (ChIP-chip and MIRA-chip)

Publications

De novo DNA methylation in the male germ line occurs by default but is excluded at sites of H3K4 methylation.

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