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Sample GSM4982833

Query DataSets for GSM4982833

Status

Public on Nov 26, 2021

Title

bovine_CC_H3K27me3_CR_rep2

Sample type

SRA

Source name

cumulus cell

Organism

Bos taurus

Characteristics

developmental stage: cumulus cell
antibody: H3K27me3

Extracted molecule

genomic DNA

Extraction protocol

CUT&RUN library preparation and sequencing CUT&RUN was performed as previously reported (Skene et al., 2018; Skene and Henikoff, 2017) with modifications. Briefly, after removing the zona pellucida with Tyrode’s solution (Sigma-Aldrich, T1788) or 0.5% (m/v) Protease from Streptomyces griseus (Sigma-Aldrich, P8811), mammalian oocytes and early embryos were incubated with Concanavalin-coated magnetic beads (Polyscience, 86057) for 10 min at room temperature on a thermomixer at 400 rpm. Samples were then incubated with primary antibody at a ratio of 1:100 at 4℃ overnight on a thermomixer at 400 rpm. The next day, after washing for one time, beads were incubated with pA-MNase (to a final concentration of 400-700ng/mL) (a gift from Steven Henikoff lab) at 4℃ for 3 hours on a thermomixer at 400 rpm. After two times of washing, targeted digestion was performed by adding 2μL of 100mM CaCl2 for 30 mins on ice, followed by termination by adding an equal volume of 2 × stop buffer. Samples were then incubated at 37℃ for 20 mins for fragment releasing. The total samples or supernatants were digested with Proteinase K (NEB, P8107S) and purified using phenol:chloroform:isoamyl alcohol (25:24:1, v/v) followed by ethanol purification at -80℃ overnight. The next day, DNA was purified and subjected to Truseq library preparation using NEBNext Ultra II DNA Library Prep Kit for Illumina (NEB, E7645S). Sequencing was done using the HiSeq X Ten system (Illumina) according to the manufacturer’s protocol.

Library strategy

OTHER

Library source

genomic

Library selection

other

Instrument model

HiSeq X Ten

Description

cow_CC_H3K27me3_CR.bw

Data processing

Library strategy: Cut&Run
Basecalls performed using CASAVA version 1.8
All STEM-seq datasets were firstly treated with cutadapt v1.11 (Martin, 2011) and the low-quality reads and adaptors were removed before mapping. Then all filtered reads were aligned to different genomes (rat, rn6; cow, bosTau8; pig, susScr11) using Bismark (v0.7.0；bowtie2 2.1.0) (Krueger and Andrews, 2011) with default parameters. Multi-mapped reads and PCR duplicates were removed also with the Bismark. The unique mapped reads were used for CpG methylation calling with bismark_methylation_extractor. For every single CpG site, only the CpG sites that were covered at least 3 times were used for further analysis. The spiked-in Lamda DNA (1:200) was used for conversation rate calculation.
All RNA-seq datasets were mapped to the different genomes (rat: rn6; cow: bosTau8; pig: susScr11). All genomes were downloaded from UCSC (citation) by Tophat v2.1.1 (Trapnell et al., 2009). Gene expression was then calculated according to refFlat database by cufflinks 2.2.1 (Trapnell et al., 2012).
All reads were firstly processed by TrimGalore (v.0.6.4) with default parameters to remove the poor qualitied reads and also the adapters. Then the filtered reads were mapped to different genomes (rat: Rn6; cow: bosTau8; pig: susScr11) by Bowtie2 (v2.2.5) (Langmead and Salzberg, 2012) with the default parameters. All multiple mapped reads as well as the duplicates were removed with MarkDuplicates.jar. Then all unique mapped reads were used for the downstream RPKM (reads per kilobase per million of sequenced reads) calculation. The Pearson correlation was generated for each sample with two biological replicates with 10 kb bins. The replicates with good reproducibility were pooled for downstream analysis.
Supplementary_files_format_and_content: The cov txt files contains the chr, start positon, methylated CG count, unmethylated CG count. The txt files for FPKM contain gene names and the FPKM value for all stages.

Submission date

Dec 21, 2020

Last update date

Nov 26, 2021

Contact name

Wei Xie

E-mail(s)

xiewei121@tsinghua.edu.cn

Organization name

Tsinghua University

Street address

Zhongguancun north street