Gene Expression Nebulas
A data portal of transcriptomic profiles analyzed by a unified pipeline across multiple species

Gene Expression Nebulas

A data portal of transcriptome profiles across multiple species

PRJNA291004: Stranded RNA-seq and methylomes for the rice DCL3a RNAi experiment

Source: NCBI / SRP061677
Submission Date: -
Release Date: Jul 30 2015
Update Date: -

Summary: Cytosine DNA methylation (mC) is a genome modification that can regulate the expression of coding and non-coding genetic elements. However, little is known about the involvement of mC in response to environmental cues. Using whole genome bisulfite sequencing to assess the spatio-temporal dynamics of mC in rice grown under phosphate starvation and recovery conditions, we identified widespread phosphate starvation-induced changes in mC, preferentially localized in transposable elements (TEs) close to highly induced genes. These changes in mC occurred after changes in nearby gene transcription, were mostly DCL3a-independent, and could partially be propagated through mitosis, however no evidence of meiotic transmission was observed. Similar analyses performed in Arabidopsis revealed a very limited effect of phosphate starvation on mC, suggesting a species-specific mechanism. Overall, this suggests that TEs in proximity to environmentally induced genes are silenced via hypermethylation, and establishes the temporal hierarchy of transcriptional and epigenomic changes in response to stress.

Overall Design: RNA-Seq of rice DCL3a and Wild type root (+Pi/-Pi), respectively.

GEN Datasets:
GEND000299
Strategy:
Species:
Tissue:
Development Stage:
Protocol
Growth Protocol: Rice (Oryza sativa L. cv. Nipponbare) was used for all physiological experiments. Hydroponic experiments were performed under controlled conditions (day/night temperature of 30/22°C and a 12 hr photoperiod, 200 µmol photons m-2 s-1), allowing 0.5 l of hydroponic solution per plant. The hydroponic solution consisted of a modified solution as described in (Secco et al., 2013a), containing 1.425 mM NH4NO3, 0.513 mM K2SO4, 0.998 mM CaCl2, 1.643 mM MgSO4, 0.075 µM (NH4)6Mo7O24, 0.25 mM NaSiO3, 0.009 mM MnCl2, 0.019 µM H3BO3, 0.155 µM CuSO4, 0.152 µM ZnSO4 and 0.125 mM EDTA-Fe, with or without 0.323 mM NaH2PO4, resulting in the +Pi and -Pi conditions. The pH of the solution was adjusted to 5.5 and the solution was renewed every 3 day.
Treatment Protocol: Rice seeds were first pre-germinated in tap water for 2 days before being transferred into the hydroponic solution, containing 0.323 mM Pi (+Pi) for 2 weeks. Half of the seedlings were then transferred to a solution lacking Pi (0 mM Pi) for 21 days, before being re-supplemented with 0.323 mM Pi for up to 31 days, while the other half of the seedlings continuously remained in +Pi conditions (control). During the resupply experiment, half of the rice seedlings were left in Pi deficient media, to serve as control. After 24 days of Pi starvation, plants grown under Pi deficient conditions were supplemented with 0.03 mM Pi (1/10th of Pi sufficient Pi concentration) until the end of the experiment to prevent them from dying.
Extract Protocol: The total RNA from the roots tissues was extracted using TRIzol reagent (Invitrogen, Carlsbad, CA), according to the manufacturer's instructions.
Library Construction Protocol: For RNA-seq library synthesis, total RNA was first depleted of rRNA using the Ribo-Zero rRNA removal kit (Plant Leaf, and Plant Seed/Root kits, Epicentre, Madison, WI). To do so, 1 µg of total RNA from root samples was used as input for rRNA removal. Sequencing libraries were generated using the TruSeq RNA Sample Prep Kit (Illumina, San Diego, CA).
Sequencing
Molecule Type: rRNA- RNA
Library Source:
Library Layout: SINGLE
Library Strand: Forward
Platform: ILLUMINA
Instrument Model: Illumina HiSeq 1000
Strand-Specific: Specific
Samples
Basic Information:
Sample Characteristic:
Biological Condition:
Experimental Variables:
Protocol:
Sequencing:
Assessing Quality:
Analysis:
Data Resource GEN Sample ID GEN Dataset ID Project ID BioProject ID Sample ID Sample Name BioSample ID Sample Accession Experiment Accession Release Date Submission Date Update Date Species Race Ethnicity Age Age Unit Gender Source Name Tissue Cell Type Cell Subtype Cell Line Disease Disease State Development Stage Mutation Phenotype Case Detail Control Detail Growth Protocol Treatment Protocol Extract Protocol Library Construction Protocol Molecule Type Library Layout Strand-Specific Library Strand Spike-In Strategy Platform Instrument Model Cell Number Reads Number Gbases AvgSpotLen1 AvgSpotLen2 Uniq Mapping Rate Multiple Mapping Rate Coverage Rate
Publications
Stress induced gene expression drives transient DNA methylation changes at adjacent repetitive elements.
eLife . 2015-07-21 [PMID: 26196146]