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Sample GSM4694783 Query DataSets for GSM4694783
Status Public on Apr 22, 2021
Title N2_1_WTcsr-1_lateL4_rep1_RNA-seq
Sample type SRA
 
Source name nematodes
Organism Caenorhabditis elegans
Characteristics genotype: N2
tissue: whole worm
developmental stage: Late L4 larval stage
treatment: none
Growth protocol Strains were maintained at 20°C, using standard methods (Brenner, 1974). Bristol N2 was the wild-type strain used.
Extracted molecule total RNA
Extraction protocol Synchronous populations of worms were grown at 20°C on NGM plates seeded with OP50 E. coli concentrated food at a density of maximum 40,000 animals per 15 cm Petri dish. Worms were carefully monitored using a stereomicroscope and sorted using COPAS bio sorter at 44 h to enrich for late L4 stage larval population. Sorted worms were frozen in dry ice with Trizol reagent (Ambion). After five repetitions of freeze and thaw in dry ice, total RNA was isolated according to the Trizol Reagent protocol. Ten micrograms of RNA were treated with 2 U of Turbo DNase (Ambion) at 37°C for 30 minutes followed by phenol-extraction and isopropanol precipitation. Agilent 2200 TapeStation System was used to evaluate the RIN indices of all the RNA preps, and only samples with RIN > 8 was used for downstream applications.
DNase-treated total RNA with RIN > 8 was used to prepare strand-specific RNA libraries. We developed an RNase H based method to degrade C. elegans and mitochondrial ribosomal RNAs (rRNAs) using 50nt oligos complementary to rRNA and mtRNA C. elegans sequences. 100 ng of DNase-treated total RNA was mixed with 1.5 µg of oligos at equimolar concentration and 1X probe hybridization buffer (200 mM NaCl, 10 mM Tris pH 7.5) and incubated in a thermocycler using the following parameters: 2 minutes at 95°C followed by 0.1°C/sec at 95-45°C, and 2 minutes hold at 45°C. Next 2 µl of Thermostable RNase H (epicentre) was added to the reactions together with 1X RNase H reaction buffer 50 mM Tris pH 7.5, 100 mM NaCl, 10 mM MgCl2) and incubated for 30 minutes at 45°C. Next, digested RNAs were treated with 2 U of Turbo DNase (Ambion) at 37°C for 30 minutes followed by purification using 2.2 volumes of Agencourt RNAClean XP Beads (Beckman Coulter, NC0068576) following the manufacturer’s instructions. 100 ng of Ribosomal-depleted RNAs were then used to generate strand-specific RNA libraries using NEBNext® Ultra™ II Directional RNA Library Prep Kit for Illumina® (E7760S). Multiplexed RNA libraries were quantified using Qubit Fluorometer High Sensitivity dsDNA assay kit (ThermoFisher, Q32851) and sequenced on NextSeq-500 Illumina platform using the NextSeq 500/550 High Output v2 kit 75 cycles (FC-404-2005).
 
Library strategy RNA-Seq
Library source transcriptomic
Library selection cDNA
Instrument model Illumina NextSeq 500
 
Description RNA-seq experiment for WT N2 for input in Ribo-seq to calculated translation efficiency
Data processing Reads were mapped on the C. elegans genome (WBcel235) using hisat2 (version 2.1.0) with default parameters
Mapped reads were used to estimate the abundance of protein coding genes using featureCounts (version 1.6.3) with options -O -M --primary -s 2 --fracOverlap 0 and annotations corresponding to protein coding genes (as annotated in the iGenome distribution of WBcel235 obtained at ftp://igenome:G3nom3s4u@ussd-ftp.illumina.com/Caenorhabditis_elegans/Ensembl/WBcel235/Caenorhabditis_elegans_Ensembl_WBcel235.tar.gz)
The alignment was used to generate the normalized bigwig file using millions of summed forward reads per kilobase in protein coding genes as normalizer. This was done with a custom bash script using bedtools (version 2.27.1), bedops (version 2.4.35) and bedGraphToBigWig (version 4)
Genome_build: C. elegans ce11 (WBcel235)
Supplementary_files_format_and_content: bigwig files allowing to display the normalized abundance of RNAs along the genome
 
Submission date Jul 24, 2020
Last update date Apr 22, 2021
Contact name Germano Cecere
E-mail(s) germano.cecere@pasteur.fr
Phone 0033140613225
Organization name Institut Pasteur
Department Development and stem cell biology
Lab Mechanisms of Epigenetic Inheritance
Street address Institut Pasteur, 28 Rue Du Docteur Roux, Batiment Monod, 4eme Etage
City Paris
ZIP/Postal code 75724
Country France
 
Platform ID GPL19757
Series (2)
GSE155074 Translation and codon usage regulate Argonaute slicer activity to trigger germline small RNA biogenesis [RNA-Seq]
GSE155077 Translation and codon usage regulate Argonaute slicer activity to trigger germline small RNA biogenesis
Relations
BioSample SAMN15639456
SRA SRX8819436

Supplementary file Size Download File type/resource
GSM4694783_N2_1_WTcsr-1_lateL4_rep1_RNA-seq_reads_by_protein_coding.bw 31.9 Mb (ftp)(http) BW
SRA Run SelectorHelp
Raw data are available in SRA
Processed data provided as supplementary file

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